Ammonia

Formula: H₃N
Molecular weight: 17.0305
IUPAC Standard InChI: InChI=1S/H3N/h1H3
IUPAC Standard InChIKey: QGZKDVFQNNGYKY-UHFFFAOYSA-N
CAS Registry Number: 7664-41-7
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
The 3d structure may be viewed using Java or Javascript.
Isotopologues:
- Ammonia-d3
Other names: Ammonia gas; Nitro-Sil; Spirit of Hartshorn; NH3; Ammonia, anhydrous; Anhydrous ammonia; Aromatic Ammonia, Vaporole
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Information on this page:
Other data available:
- Reaction thermochemistry data: reactions 51 to 100, reactions 101 to 146
- Henry's Law data
- Vibrational and/or electronic energy levels
- Fluid Properties
Data at other public NIST sites:
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Gas phase thermochemistry data

Go To: Top, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Quantity	Value	Units	Method	Reference	Comment
Δ_fH°_gas	-10.98 ± 0.084	kcal/mol	Review	Cox, Wagman, et al., 1984	CODATA Review value
Δ_fH°_gas	-10.97	kcal/mol	Review	Chase, 1998	Data last reviewed in June, 1977
Quantity	Value	Units	Method	Reference	Comment
S°_{gas,1 bar}	46.07 ± 0.01	cal/mol*K	Review	Cox, Wagman, et al., 1984	CODATA Review value
S°_{gas,1 bar}	46.073	cal/mol*K	Review	Chase, 1998	Data last reviewed in June, 1977

Gas Phase Heat Capacity (Shomate Equation)

C_p° = A + B*t + C*t² + D*t³ + E/t²
H° − H°_298.15= A*t + B*t²/2 + C*t³/3 + D*t⁴/4 − E/t + F − H
S° = A*ln(t) + B*t + C*t²/2 + D*t³/3 − E/(2*t²) + G
C_p = heat capacity (cal/mol*K)
H° = standard enthalpy (kcal/mol)
S° = standard entropy (cal/mol*K)
t = temperature (K) / 1000.

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Temperature (K)	298. to 1400.	1400. to 6000.
A	4.779071	12.43410
B	11.89560	4.418741
C	-3.674950	-0.899887
D	0.459170	0.059403
E	0.045214	-2.977532
F	-12.74060	-20.44430
G	48.72349	53.49001
H	-10.96990	-10.96990
Reference	Chase, 1998	Chase, 1998
Comment	Data last reviewed in June, 1977	Data last reviewed in June, 1977

Phase change data

Go To: Top, Gas phase thermochemistry data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director
AC - William E. Acree, Jr., James S. Chickos

Quantity	Value	Units	Method	Reference	Comment
T_fus	194.95	K	N/A	Timmermans, 1921	Uncertainty assigned by TRC = 0.3 K; TRC
Quantity	Value	Units	Method	Reference	Comment
P_triple	0.05981	atm	N/A	Fonseca and Lobo, 1989	Uncertainty assigned by TRC = 0.00005 atm; TRC
Quantity	Value	Units	Method	Reference	Comment
T_c	405.4	K	N/A	Brunner, 1988	Uncertainty assigned by TRC = 0.1 K; TRC
T_c	405.6	K	N/A	Hentze, 1977	Uncertainty assigned by TRC = 5. K; TRC
Quantity	Value	Units	Method	Reference	Comment
P_c	111.52	atm	N/A	Brunner, 1988	Uncertainty assigned by TRC = 0.05 atm; TRC

Enthalpy of vaporization

Δ_vapH (kcal/mol)	Temperature (K)	Method	Reference	Comment
5.43	308.	N/A	Zander and Thomas, 1979	Based on data from 293. to 392. K.; AC
5.62	239.	N/A	Overstreet and Giauque, 1937	Based on data from 199. to 241. K.; AC
5.59	239.	C	Overstreet and Giauque, 1937	AC

Antoine Equation Parameters

log₁₀(P) = A − (B / (T + C))
P = vapor pressure (atm)
T = temperature (K)

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Temperature (K)	A	B	C	Reference	Comment
164.0 to 239.6	3.18186	506.713	-80.78	Stull, 1947	Coefficents calculated by NIST from author's data.
239.6 to 371.5	4.86315	1113.928	-10.409	Stull, 1947	Coefficents calculated by NIST from author's data.

Enthalpy of sublimation

Δ_subH (kcal/mol)	Temperature (K)	Reference	Comment
7.46	177. to 195.	Overstreet and Giauque, 1937	AC

In addition to the Thermodynamics Research Center (TRC) data available from this site, much more physical and chemical property data is available from the following TRC products:

Reaction thermochemistry data

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

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Reactions 1 to 50

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (H₄N⁺ • 3H₃N) + H₃N = (H₄N⁺ • 4H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.2 ± 0.9	kcal/mol	AVG	N/A	Average of 5 out of 10 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28. ± 2.	cal/mol*K	AVG	N/A	Average of 3 out of 7 values; Individual data points

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
3.4	296.	FA	Fehsenfeld and Ferguson, 1973	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (H₄N⁺ • 2H₃N) + H₃N = (H₄N⁺ • 3H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13. ± 5.	kcal/mol	AVG	N/A	Average of 6 out of 9 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25. ± 1.	cal/mol*K	AVG	N/A	Average of 4 out of 7 values; Individual data points

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
6.5	296.	FA	Fehsenfeld and Ferguson, 1973	gas phase; M
6.4	296.	SAMS	Puckett and Teague, 1971	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (H₄N⁺ • H₃N) + H₃N = (H₄N⁺ • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17. ± 1.	kcal/mol	AVG	N/A	Average of 5 out of 8 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.9	cal/mol*K	HPMS	Tang and Castleman, 1975	gas phase; M
Δ_rS°	23.7	cal/mol*K	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rS°	24.8	cal/mol*K	DT	Long and Franklin, 1973	gas phase; M
Δ_rS°	26.8	cal/mol*K	PHPMS	Searles and Kebarle, 1968	gas phase; M
Δ_rS°	22.9	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; typographical error in Δ_rH; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
9.7	296.	FA	Fehsenfeld and Ferguson, 1973	gas phase; DG>; M
10.1	296.	SAMS	Puckett and Teague, 1971	gas phase; M
5.5	400.	HPMS	Wincel, 1972	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: H₄N⁺ + H₃N = (H₄N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	26. ± 2.	kcal/mol	AVG	N/A	Average of 4 out of 9 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	26. ± 3.	cal/mol*K	AVG	N/A	Average of 4 out of 6 values; Individual data points

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
6.3	400.	HPMS	Wincel, 1972	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Cl^- + H₃N = (Cl^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	<7.30 ± 0.40	kcal/mol	N/A	Tschurl and Boesl, 2008	gas phase; B
Δ_rH°	8.20 ± 0.10	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B,M
Δ_rH°	8.9 ± 1.2	kcal/mol	N/A	Markovich, Chesnovsky, et al., 1993	gas phase; B
Δ_rH°	10.5 ± 4.0	kcal/mol	IMRE	Larson and McMahon, 1984	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	15.4	cal/mol*K	HPMS	Evans, Keesee, et al., 1987	gas phase; M
Δ_rS°	19.9	cal/mol*K	N/A	Larson and McMahon, 1984	gas phase; switching reaction(Cl-)CH3F, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	3.60 ± 0.20	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B
Δ_rG°	4.5 ± 2.0	kcal/mol	IMRE	Larson and McMahon, 1984	gas phase; B,M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (H₄N⁺ • 4H₃N) + H₃N = (H₄N⁺ • 5H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.0	kcal/mol	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rH°	7.5	kcal/mol	PHPMS	Searles and Kebarle, 1968	gas phase; M
Δ_rH°	7.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M
Δ_rH°	2.8	kcal/mol	TPEPICO	Kamke, Herrmann, et al., 1988	gas phase; M
Δ_rH°	9.6	kcal/mol	DT	Long and Franklin, 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.5	cal/mol*K	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rS°	25.	cal/mol*K	PHPMS	Searles and Kebarle, 1968	gas phase; M
Δ_rS°	32.	cal/mol*K	DT	Long and Franklin, 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	0.5	kcal/mol	HPMS	Hogg, Haynes, et al., 1966	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Li⁺ + H₃N = (Li⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	39.1	kcal/mol	ICR	Woodin and Beauchamp, 1978	gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M
Δ_rH°	38.5	kcal/mol	ICR	Staley and Beauchamp, 1975	gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 extrapolated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.	cal/mol*K	N/A	Woodin and Beauchamp, 1978	gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	32.1	kcal/mol	ICR	Woodin and Beauchamp, 1978	gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Na⁺ • H₃N) + H₃N = (Na⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	22. ± 1.	kcal/mol	AVG	N/A	Average of 6 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.1	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

H₂N^- + = Ammonia

By formula: H₂N^- + H⁺ = H₃N

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	403.44 ± 0.28	kcal/mol	D-EA	Wickham-Jones, Ervin, et al., 1989	gas phase; B
Δ_rH°	403.55 ± 0.80	kcal/mol	G+TS	MacKay, Hemsworth, et al., 1976	gas phase; B
Δ_rH°	402.30	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; HCrO3(t); ; ΔS(EA)=6.6; B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	395.99 ± 0.38	kcal/mol	H-TS	Wickham-Jones, Ervin, et al., 1989	gas phase; B
Δ_rG°	396.10 ± 0.70	kcal/mol	IMRE	MacKay, Hemsworth, et al., 1976	gas phase; B
Δ_rG°	395.40	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; HCrO3(t); ; ΔS(EA)=6.6; B

C₄H₉⁺ + Ammonia = (C₄H₉⁺ • Ammonia )

By formula: C₄H₉⁺ + H₃N = (C₄H₉⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	46.8	kcal/mol	PHPMS	Meot-Ner (Mautner) and Sieck, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rH°	45.3	kcal/mol	PHPMS	Szulejko and McMahon, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rH°	46.5	kcal/mol	PHPMS	Meot-Ner (Mautner) and Sieck, 1990	gas phase; forms t-C4H9NH3+; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	43.7	cal/mol*K	PHPMS	Meot-Ner (Mautner) and Sieck, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rS°	47.3	cal/mol*K	PHPMS	Szulejko and McMahon, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rS°	44.0	cal/mol*K	PHPMS	Meot-Ner (Mautner) and Sieck, 1990	gas phase; forms t-C4H9NH3+; M

+ Ammonia = ( • Ammonia )

By formula: Na⁺ + H₃N = (Na⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	24.4 ± 1.3	kcal/mol	CIDC	Amicangelo and Armentrout, 2001	Anchor NH3=24.41; RCD
Δ_rH°	24.4 ± 1.3	kcal/mol	CIDT	Armentrout and Rodgers, 2000	RCD
Δ_rH°	25.6 ± 0.2	kcal/mol	HPMS	Hoyau, Norrman, et al., 1999	RCD
Δ_rH°	29.1	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21800.	cal/mol*K	HPMS	Hoyau, Norrman, et al., 1999	RCD
Δ_rS°	25.7	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
18.6	298.	IMRE	McMahon and Ohanessian, 2000	Anchor alanine=39.89; RCD

C₃H₉Sn⁺ + Ammonia = (C₃H₉Sn⁺ • Ammonia )

By formula: C₃H₉Sn⁺ + H₃N = (C₃H₉Sn⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	36.9	kcal/mol	PHPMS	Stone and Splinter, 1984	gas phase; switching reaction((CH3)3Sn+)CH3OH/NH3, Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	29.1	cal/mol*K	N/A	Stone and Splinter, 1984	gas phase; switching reaction((CH3)3Sn+)CH3OH/NH3, Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
21.6	525.	PHPMS	Stone and Splinter, 1984	gas phase; switching reaction((CH3)3Sn+)CH3OH/NH3, Entropy change calculated or estimated; M

( • 3 • Ammonia ) + = ( • 4 • Ammonia )

By formula: (H₄N⁺ • 3CHN • H₃N) + CHN = (H₄N⁺ • 4CHN • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.6	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated, T = 392 in paper is error; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated, T = 392 in paper is error; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
2.7	292.	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated, T = 392 in paper is error; M

+ Ammonia = ( • Ammonia )

By formula: I^- + H₃N = (I^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.40 ± 0.30	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B,M
Δ_rH°	7.4 ± 1.0	kcal/mol	TDAs	Caldwell, Masucci, et al., 1989	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.9	cal/mol*K	HPMS	Evans, Keesee, et al., 1987	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	1.20 ± 0.60	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B

( • Ammonia • 2) + Ammonia = ( • 2 Ammonia • 2)

By formula: (H₄N⁺ • H₃N • 2CHN) + H₃N = (H₄N⁺ • 2H₃N • 2CHN)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.9	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
6.6	315.	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

( • • 2 Ammonia ) + = ( • 2 • 2 Ammonia )

By formula: (H₄N⁺ • CHN • 2H₃N) + CHN = (H₄N⁺ • 2CHN • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.2	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
4.9	315.	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

( • ) + Ammonia = ( • Ammonia • )

By formula: (H₄N⁺ • CHN) + H₃N = (H₄N⁺ • H₃N • CHN)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.8	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
9.4	429.	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

+ Ammonia = ( • Ammonia )

By formula: Br^- + H₃N = (Br^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.70 ± 0.10	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.1	cal/mol*K	HPMS	Evans, Keesee, et al., 1987	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	2.00 ± 0.20	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B

( • 5 Ammonia ) + Ammonia = ( • 6 Ammonia )

By formula: (H₄N⁺ • 5H₃N) + H₃N = (H₄N⁺ • 6H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.5	kcal/mol	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rH°	6.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.9	cal/mol*K	PHPMS	Arshadi and Futrell, 1974	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: K⁺ + H₃N = (K⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.1	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Δ_rH°	17.8	kcal/mol	HPMS	Davidson and Kebarle, 1976	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.0	cal/mol*K	HPMS	Castleman, 1978	gas phase; M
Δ_rS°	28.0	cal/mol*K	HPMS	Davidson and Kebarle, 1976	gas phase; M

( • 2 Ammonia ) + = ( • • 2 Ammonia )

By formula: (H₄N⁺ • 2H₃N) + CHN = (H₄N⁺ • CHN • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.4	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	18.3	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

( • Ammonia • 2) + Ammonia = ( • 2 Ammonia • 2)

By formula: (H₄N⁺ • H₃N • 2H₂O) + H₃N = (H₄N⁺ • 2H₃N • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.7	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	33.9	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • • 2 Ammonia ) + = ( • 2 • 2 Ammonia )

By formula: (H₄N⁺ • H₂O • 2H₃N) + H₂O = (H₄N⁺ • 2H₂O • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.7	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.8	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

(C₆H₁₅O₃⁺ • Ammonia ) + = (C₆H₁₅O₃⁺ • • Ammonia )

By formula: (C₆H₁₅O₃⁺ • H₃N) + C₆H₁₄O₃ = (C₆H₁₅O₃⁺ • C₆H₁₄O₃ • H₃N)

Bond type: Hydrogen bonds between protonated and neutral organics

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	30.5	kcal/mol	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	50.9	cal/mol*K	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M

( • 2 Ammonia • ) + Ammonia = ( • 3 Ammonia • )

By formula: (H₄N⁺ • 2H₃N • H₂O) + H₃N = (H₄N⁺ • 3H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.0	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	34.3	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 2 • Ammonia ) + = ( • 3 • Ammonia )

By formula: (H₄N⁺ • 2H₂O • H₃N) + H₂O = (H₄N⁺ • 3H₂O • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.2	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.5	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • Ammonia • ) + Ammonia = ( • 2 Ammonia • )

By formula: (H₄N⁺ • H₃N • H₂O) + H₃N = (H₄N⁺ • 2H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17.1	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	31.8	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • • Ammonia ) + = ( • 2 • Ammonia )

By formula: (H₄N⁺ • H₂O • H₃N) + H₂O = (H₄N⁺ • 2H₂O • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.7	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.0	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 2 Ammonia ) + = ( • • 2 Ammonia )

By formula: (H₄N⁺ • 2H₃N) + H₂O = (H₄N⁺ • H₂O • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.4	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.6	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 2) + Ammonia = ( • Ammonia • 2)

By formula: (H₄N⁺ • 2H₂O) + H₃N = (H₄N⁺ • H₃N • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.2	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	30.3	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 3 Ammonia ) + = ( • • 3 Ammonia )

By formula: (H₄N⁺ • 3H₃N) + H₂O = (H₄N⁺ • H₂O • 3H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.7	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.9	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 3) + Ammonia = ( • Ammonia • 3)

By formula: (H₄N⁺ • 3H₂O) + H₃N = (H₄N⁺ • H₃N • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17.3	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	35.1	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • Ammonia ) + = ( • • Ammonia )

By formula: (H₄N⁺ • H₃N) + H₂O = (H₄N⁺ • H₂O • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.9	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.3	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • ) + Ammonia = ( • Ammonia • )

By formula: (H₄N⁺ • H₂O) + H₃N = (H₄N⁺ • H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.4	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.0	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • ) + Ammonia = ( • Ammonia • )

By formula: (H₄N⁺ • C₄H₁₀O₂) + H₃N = (H₄N⁺ • H₃N • C₄H₁₀O₂)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	14.0	kcal/mol	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.4	cal/mol*K	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: H^- + H₃N = (H^- • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.10	kcal/mol	Est	Snodgrass, Coe, et al., 1995	gas phase; Stated electron affinity is the Vertical Detachment Energy; B
Δ_rH°	8.3	kcal/mol	PES	Coe, Snodgrass, et al., 1985	gas phase; Δ_rH<; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Cu⁺ • 2H₃N) + H₃N = (Cu⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.2 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	14.0	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.8	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Cu⁺ • 3H₃N) + H₃N = (Cu⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.0 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	12.8	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.7	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Pb⁺ • 2H₃N) + H₃N = (Pb⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.0	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.4	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Pb⁺ • 3H₃N) + H₃N = (Pb⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.7	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.3	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Pb⁺ • H₃N) + H₃N = (Pb⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	19.2	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.0	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

C₂H₈N⁺ + Ammonia = (C₂H₈N⁺ • Ammonia )

By formula: C₂H₈N⁺ + H₃N = (C₂H₈N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.6	kcal/mol	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.2	cal/mol*K	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M

C₆H₁₅O₃⁺ + Ammonia = (C₆H₁₅O₃⁺ • Ammonia )

By formula: C₆H₁₅O₃⁺ + H₃N = (C₆H₁₅O₃⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	30.4	kcal/mol	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.9	cal/mol*K	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M

CH₆N⁺ + Ammonia = (CH₆N⁺ • Ammonia )

By formula: CH₆N⁺ + H₃N = (CH₆N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	21.4	kcal/mol	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	26.	cal/mol*K	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Pb⁺ + H₃N = (Pb⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	28.3	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.6	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (H^- • H₃N) + H₃N = (H^- • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.10	kcal/mol	Est	Snodgrass, Coe, et al., 1995	gas phase; Affinity: shift in apparent EA from lesser-solvated ion. Ignores any neutral-neutral bond.; B

(H₂N^- • Ammonia ) + Ammonia = (H₂N^- • 2 Ammonia )

By formula: (H₂N^- • H₃N) + H₃N = (H₂N^- • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.10	kcal/mol	Est	Snodgrass, Coe, et al., 1989	gas phase; Affinity: shift in apparent EA from lesser-solvated ion. Ignores any neutral-neutral bond.; B

( • 2 • Ammonia ) + = ( • 3 • Ammonia )

By formula: (H₄N⁺ • 2CHN • H₃N) + CHN = (H₄N⁺ • 3CHN • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.8	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.1	cal/mol*K	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; M

( • • Ammonia ) + = ( • 2 • Ammonia )

By formula: (H₄N⁺ • CHN • H₃N) + CHN = (H₄N⁺ • 2CHN • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.2	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.4	cal/mol*K	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; M

( • 2 Ammonia • ) + Ammonia = ( • 3 Ammonia • )

By formula: (H₄N⁺ • 2H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 3H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.6	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data evaluated as indicated in comments:
HL - Edward P. Hunter and Sharon G. Lias
L - Sharon G. Lias

Data compiled as indicated in comments:
B - John E. Bartmess
LL - Sharon G. Lias and Joel F. Liebman
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

View reactions leading to H₃N⁺ (ion structure unspecified)

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	10.070 ± 0.020	eV	N/A	N/A	L
Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	204.0	kcal/mol	N/A	Hunter and Lias, 1998	HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	195.7	kcal/mol	N/A	Hunter and Lias, 1998	HL

Ionization energy determinations

IE (eV)	Method	Reference	Comment
10.02	PI	Qi, Sheng, et al., 1995	T = 0K; LL
10.07 ± 0.01	PIPECO	Ruede, Troxler, et al., 1993	LL
10.186	TE	Reiser, Habenicht, et al., 1993	LL
10.069 ± 0.002	PI	Locht, Hottmann, et al., 1992	LL
10.072 ± 0.010	PI	Locht, Leyh, et al., 1991	LL
10.2985 ± 0.0001	TE	Habenicht, 1989	LL
10.45	EI	Baldwin, Loudon, et al., 1977	LLK
10.2	PE	Debies and Rabalais, 1975	LLK
10.18 ± 0.09	PE	Aue, Webb, et al., 1975	LLK
10.2	EI	Morrison and Traeger, 1973	LLK
10.15	PE	Potts and Price, 1972	LLK
10.18 ± 0.01	PE	Weiss and Lawrence, 1970	RDSH
14.94 ± 0.03	PE	Weiss and Lawrence, 1970	RDSH
10.14	PE	Branton, Frost, et al., 1969	RDSH
14.92	PE	Branton, Frost, et al., 1969	RDSH
10.16 ± 0.02	PI	Potapov, 1968	RDSH
10.17	PI	Chupka and Russell, 1968	RDSH
10.162 ± 0.008	PI	Dibeler, Walker, et al., 1966	RDSH
10.166	S	Watanabe and Sood, 1965	RDSH
10.16	PE	Al-Joboury and Turner, 1964	RDSH
15.02	PE	Al-Joboury and Turner, 1964	RDSH
10.15 ± 0.01	PI	Watanabe and Mottl, 1957	RDSH
10.82	PE	Baumgartel, Jochims, et al., 1989	Vertical value; LL
10.8	PE	Bieri, Asbrink, et al., 1982	Vertical value; LBLHLM
10.85	PE	Kimura, Katsumata, et al., 1981	Vertical value; LLK
11.3	PE	Campbell, Liesegang, et al., 1979	Vertical value; LLK
10.85	PE	Daamen and Oskam, 1978	Vertical value; LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
H⁺	18.57	H₂N	PI	Qi, Sheng, et al., 1995	LL
HN⁺	28. ± 1.5	H₂/2H	EI	Muller and Schulz, 1990	LL
HN⁺	16.9 ± 0.1	H₂	EI	Locht, Servais, et al., 1988	LL
HN⁺	17.2	H₂	EI	Morrison and Traeger, 1973	LLK
NH⁺	17.1 ± 0.1	H₂	EI	Reed and Snedden, 1959	RDSH
H₂N⁺	15.75	H	PI	Qi, Sheng, et al., 1995	LL
H₂N⁺	15.60 ± 0.02	H	PIPECO	Ruede, Troxler, et al., 1993	LL
H₂N⁺	15.75	H	PI	Locht, Hottmann, et al., 1992	LL
H₂N⁺	15.76 ± 0.05	H	PI	Locht, Servais, et al., 1988	LL
H₂N⁺	15.76 ± 0.05	H	EI	Locht, Servais, et al., 1988	LL
H₂N⁺	15.5	H	PIPECO	Powis, 1981	LLK
H₂N⁺	15.87 ± 0.13	H	DER	Powis, 1981	LLK
H₂N⁺	15.768 ± 0.004	H	PI	McCulloh, 1976	LLK
H₂N⁺	15.0	H	EI	Morrison and Traeger, 1973	LLK
NH₂⁺	15.73 ± 0.02	H	PI	Dibeler, Walker, et al., 1966	RDSH
NH₂⁺	16.0 ± 0.1	H	EI	Foner and Hudson, 1958	RDSH
N⁺	≤22.5	H₂+H	EI	Morrison and Traeger, 1973	LLK
N⁺	22.6 ± 0.1	H₂+H	EI	Reed and Snedden, 1959	RDSH

De-protonation reactions

H₂N^- + = Ammonia

By formula: H₂N^- + H⁺ = H₃N

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	403.44 ± 0.28	kcal/mol	D-EA	Wickham-Jones, Ervin, et al., 1989	gas phase; B
Δ_rH°	403.55 ± 0.80	kcal/mol	G+TS	MacKay, Hemsworth, et al., 1976	gas phase; B
Δ_rH°	402.30	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; HCrO3(t); ; ΔS(EA)=6.6; B
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	395.99 ± 0.38	kcal/mol	H-TS	Wickham-Jones, Ervin, et al., 1989	gas phase; B
Δ_rG°	396.10 ± 0.70	kcal/mol	IMRE	MacKay, Hemsworth, et al., 1976	gas phase; B
Δ_rG°	395.40	kcal/mol	N/A	Check, Faust, et al., 2001	gas phase; HCrO3(t); ; ΔS(EA)=6.6; B

Ion clustering data

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled as indicated in comments:
M - Michael M. Meot-Ner (Mautner) and Sharon G. Lias
B - John E. Bartmess
RCD - Robert C. Dunbar

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. Searches may be limited to ion clustering reactions. A general reaction search form is also available.

Clustering reactions

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Ag⁺ • H₃N) + H₃N = (Ag⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	36.9	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	32.7	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Ag⁺ • 2H₃N) + H₃N = (Ag⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	14.6	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.6	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Ag⁺ • 3H₃N) + H₃N = (Ag⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.0	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	30.0	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (Ag⁺ • 4H₃N) + H₃N = (Ag⁺ • 5H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.8	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	34.1	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Bi⁺ + H₃N = (Bi⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	35.5	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	35.7	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Bi⁺ • H₃N) + H₃N = (Bi⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	23.2	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	33.0	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Bi⁺ • 2H₃N) + H₃N = (Bi⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.4	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	26.0	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Br^- + H₃N = (Br^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.70 ± 0.10	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.1	cal/mol*K	HPMS	Evans, Keesee, et al., 1987	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	2.00 ± 0.20	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B

CH₆N⁺ + Ammonia = (CH₆N⁺ • Ammonia )

By formula: CH₆N⁺ + H₃N = (CH₆N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	21.4	kcal/mol	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	26.	cal/mol*K	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M

C₂H₈N⁺ + Ammonia = (C₂H₈N⁺ • Ammonia )

By formula: C₂H₈N⁺ + H₃N = (C₂H₈N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.6	kcal/mol	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.2	cal/mol*K	PHPMS	Yamdagni and Kebarle, 1974	gas phase; M

C₃H₉Si⁺ + Ammonia = (C₃H₉Si⁺ • Ammonia )

By formula: C₃H₉Si⁺ + H₃N = (C₃H₉Si⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	46.5	kcal/mol	PHPMS	Li and Stone, 1990	gas phase; switching reaction((CH3)3Si+)CH3COOC2H5; Wojtyniak and Stone, 1986; M

C₃H₉Sn⁺ + Ammonia = (C₃H₉Sn⁺ • Ammonia )

By formula: C₃H₉Sn⁺ + H₃N = (C₃H₉Sn⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	36.9	kcal/mol	PHPMS	Stone and Splinter, 1984	gas phase; switching reaction((CH3)3Sn+)CH3OH/NH3, Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	29.1	cal/mol*K	N/A	Stone and Splinter, 1984	gas phase; switching reaction((CH3)3Sn+)CH3OH/NH3, Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
21.6	525.	PHPMS	Stone and Splinter, 1984	gas phase; switching reaction((CH3)3Sn+)CH3OH/NH3, Entropy change calculated or estimated; M

C₄H₉⁺ + Ammonia = (C₄H₉⁺ • Ammonia )

By formula: C₄H₉⁺ + H₃N = (C₄H₉⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	46.8	kcal/mol	PHPMS	Meot-Ner (Mautner) and Sieck, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rH°	45.3	kcal/mol	PHPMS	Szulejko and McMahon, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rH°	46.5	kcal/mol	PHPMS	Meot-Ner (Mautner) and Sieck, 1990	gas phase; forms t-C4H9NH3+; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	43.7	cal/mol*K	PHPMS	Meot-Ner (Mautner) and Sieck, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rS°	47.3	cal/mol*K	PHPMS	Szulejko and McMahon, 1991	gas phase; forms t-C4H9NH3+; M
Δ_rS°	44.0	cal/mol*K	PHPMS	Meot-Ner (Mautner) and Sieck, 1990	gas phase; forms t-C4H9NH3+; M

C₅H₁₀NO₂⁺ + Ammonia = (C₅H₁₀NO₂⁺ • Ammonia )

By formula: C₅H₁₀NO₂⁺ + H₃N = (C₅H₁₀NO₂⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.6	kcal/mol	PHPMS	Meot-Ner and Field, 1974	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.9	cal/mol*K	PHPMS	Meot-Ner and Field, 1974	gas phase; M

C₅H₁₂NO₂⁺ + Ammonia = (C₅H₁₂NO₂⁺ • Ammonia )

By formula: C₅H₁₂NO₂⁺ + H₃N = (C₅H₁₂NO₂⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.9	kcal/mol	PHPMS	Meot-Ner and Field, 1974	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.8	cal/mol*K	PHPMS	Meot-Ner and Field, 1974	gas phase; M

C₆H₁₅O₃⁺ + Ammonia = (C₆H₁₅O₃⁺ • Ammonia )

By formula: C₆H₁₅O₃⁺ + H₃N = (C₆H₁₅O₃⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	30.4	kcal/mol	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.9	cal/mol*K	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Cl^- + H₃N = (Cl^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	<7.30 ± 0.40	kcal/mol	N/A	Tschurl and Boesl, 2008	gas phase; B
Δ_rH°	8.20 ± 0.10	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B,M
Δ_rH°	8.9 ± 1.2	kcal/mol	N/A	Markovich, Chesnovsky, et al., 1993	gas phase; B
Δ_rH°	10.5 ± 4.0	kcal/mol	IMRE	Larson and McMahon, 1984	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	15.4	cal/mol*K	HPMS	Evans, Keesee, et al., 1987	gas phase; M
Δ_rS°	19.9	cal/mol*K	N/A	Larson and McMahon, 1984	gas phase; switching reaction(Cl-)CH3F, Entropy change calculated or estimated; Larson and McMahon, 1984, 2; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	3.60 ± 0.20	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B
Δ_rG°	4.5 ± 2.0	kcal/mol	IMRE	Larson and McMahon, 1984	gas phase; B,M

+ Ammonia = ( • Ammonia )

By formula: Co⁺ + H₃N = (Co⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	52.1 ± 3.6	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	58.8	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Co⁺ • H₃N) + H₃N = (Co⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	59.3 ± 3.1	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	61.1	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Co⁺ • 2H₃N) + H₃N = (Co⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.3 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Co⁺ • 3H₃N) + H₃N = (Co⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.7 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

+ Ammonia = ( • Ammonia )

By formula: Cr⁺ + H₃N = (Cr⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	43.5 ± 2.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	37.4	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Cr⁺ • H₃N) + H₃N = (Cr⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	42.8 ± 2.2	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	40.8	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Cr⁺ • 2H₃N) + H₃N = (Cr⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.9 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Cr⁺ • 3H₃N) + H₃N = (Cr⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.2 ± 2.2	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

+ Ammonia = ( • Ammonia )

By formula: Cu⁺ + H₃N = (Cu⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	56.6 ± 3.3	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Cu⁺ • H₃N) + H₃N = (Cu⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	58.8 ± 2.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Cu⁺ • 2H₃N) + H₃N = (Cu⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.2 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	14.0	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.8	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Cu⁺ • 3H₃N) + H₃N = (Cu⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.0 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	12.8	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.7	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (Cu⁺ • 4H₃N) + H₃N = (Cu⁺ • 5H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.8	kcal/mol	HPMS	Holland and Castleman, 1982	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	33.1	cal/mol*K	HPMS	Holland and Castleman, 1982	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: F^- + H₃N = (F^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	23.	kcal/mol	FA	Spears and Ferguson, 1973	gas phase; Δ_rH>; M

+ Ammonia = ( • Ammonia )

By formula: Fe⁺ + H₃N = (Fe⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	43.7 ± 2.9	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	38.5	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Fe⁺ • H₃N) + H₃N = (Fe⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	53.8 ± 2.9	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	48.7	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Fe⁺ • 2H₃N) + H₃N = (Fe⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.3 ± 3.1	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Fe⁺ • 3H₃N) + H₃N = (Fe⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.0 ± 1.7	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

+ Ammonia = ( • Ammonia )

By formula: H^- + H₃N = (H^- • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.10	kcal/mol	Est	Snodgrass, Coe, et al., 1995	gas phase; Stated electron affinity is the Vertical Detachment Energy; B
Δ_rH°	8.3	kcal/mol	PES	Coe, Snodgrass, et al., 1985	gas phase; Δ_rH<; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (H^- • H₃N) + H₃N = (H^- • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.10	kcal/mol	Est	Snodgrass, Coe, et al., 1995	gas phase; Affinity: shift in apparent EA from lesser-solvated ion. Ignores any neutral-neutral bond.; B

HO^- + Ammonia = H₄NO^-

By formula: HO^- + H₃N = H₄NO^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.00	kcal/mol	N/A	Schwartz, Davico, et al., 2000	gas phase; Vertical Detachment Energy: 2.54±0.015 eV. Affinity is from difference in EAs; B

H₂N^- + Ammonia = (H₂N^- • Ammonia )

By formula: H₂N^- + H₃N = (H₂N^- • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.00	kcal/mol	PDis	Snodgrass, Coe, et al., 1989	gas phase; B

(H₂N^- • Ammonia ) + Ammonia = (H₂N^- • 2 Ammonia )

By formula: (H₂N^- • H₃N) + H₃N = (H₂N^- • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.10	kcal/mol	Est	Snodgrass, Coe, et al., 1989	gas phase; Affinity: shift in apparent EA from lesser-solvated ion. Ignores any neutral-neutral bond.; B

H₃N⁺ + Ammonia = (H₃N⁺ • Ammonia )

By formula: H₃N⁺ + H₃N = (H₃N⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	23.1 ± 4.6	kcal/mol	EI	Stephan, Futrell, et al., 1982	gas phase; M
Δ_rH°	18.1	kcal/mol	PI	Ng, Trevor, et al., 1977	gas phase; M

(H₃N⁺ • Ammonia ) + Ammonia = (H₃N⁺ • 2 Ammonia )

By formula: (H₃N⁺ • H₃N) + H₃N = (H₃N⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	9. ± 5.	kcal/mol	EI	Breen, Tzeng, et al., 1989	gas phase; M
Δ_rH°	9.2 ± 4.6	kcal/mol	EI	Stephan, Futrell, et al., 1982	gas phase; M

( • ) + Ammonia = ( • Ammonia • )

By formula: (H₄N⁺ • CHN) + H₃N = (H₄N⁺ • H₃N • CHN)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.8	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
9.4	429.	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

( • ) + Ammonia = ( • Ammonia • )

By formula: (H₄N⁺ • C₄H₁₀O₂) + H₃N = (H₄N⁺ • H₃N • C₄H₁₀O₂)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	14.0	kcal/mol	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.4	cal/mol*K	PHPMS	Meot-Ner (Mautner), Sieck, et al., 1996	gas phase; M

( • ) + Ammonia = ( • Ammonia • )

By formula: (H₄N⁺ • H₂O) + H₃N = (H₄N⁺ • H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.4	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.0	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 2) + Ammonia = ( • Ammonia • 2)

By formula: (H₄N⁺ • 2H₂O) + H₃N = (H₄N⁺ • H₃N • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.2	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	30.3	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 3) + Ammonia = ( • Ammonia • 3)

By formula: (H₄N⁺ • 3H₂O) + H₃N = (H₄N⁺ • H₃N • 3H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17.3	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	35.1	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: H₄N⁺ + H₃N = (H₄N⁺ • H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	26. ± 2.	kcal/mol	AVG	N/A	Average of 4 out of 9 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	26. ± 3.	cal/mol*K	AVG	N/A	Average of 4 out of 6 values; Individual data points

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
6.3	400.	HPMS	Wincel, 1972	gas phase; M

( • Ammonia • 2) + Ammonia = ( • 2 Ammonia • 2)

By formula: (H₄N⁺ • H₃N • 2CHN) + H₃N = (H₄N⁺ • 2H₃N • 2CHN)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.9	kcal/mol	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.	cal/mol*K	N/A	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
6.6	315.	PHPMS	Deakyne, Knuth, et al., 1994	gas phase; Entropy change calculated or estimated; M

( • Ammonia • ) + Ammonia = ( • 2 Ammonia • )

By formula: (H₄N⁺ • H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 2H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.5	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 2 Ammonia • ) + Ammonia = ( • 3 Ammonia • )

By formula: (H₄N⁺ • 2H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 3H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.6	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 3 Ammonia • ) + Ammonia = ( • 4 Ammonia • )

By formula: (H₄N⁺ • 3H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 4H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.4	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 4 Ammonia • ) + Ammonia = ( • 5 Ammonia • )

By formula: (H₄N⁺ • 4H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 5H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.9	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 5 Ammonia • ) + Ammonia = ( • 6 Ammonia • )

By formula: (H₄N⁺ • 5H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 6H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.0	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 6 Ammonia • ) + Ammonia = ( • 7 Ammonia • )

By formula: (H₄N⁺ • 6H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 7H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.5	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 7 Ammonia • ) + Ammonia = ( • 8 Ammonia • )

By formula: (H₄N⁺ • 7H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 8H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.0	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • 8 Ammonia • ) + Ammonia = ( • 9 Ammonia • )

By formula: (H₄N⁺ • 8H₃N • C₂H₃N) + H₃N = (H₄N⁺ • 9H₃N • C₂H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.5	kcal/mol	MKER	Tzeng, Wei, et al., 1991	gas phase; from graph; M

( • Ammonia • ) + Ammonia = ( • 2 Ammonia • )

By formula: (H₄N⁺ • H₃N • H₂O) + H₃N = (H₄N⁺ • 2H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17.1	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	31.8	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • Ammonia • 2) + Ammonia = ( • 2 Ammonia • 2)

By formula: (H₄N⁺ • H₃N • 2H₂O) + H₃N = (H₄N⁺ • 2H₃N • 2H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.7	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	33.9	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • 2 Ammonia • ) + Ammonia = ( • 3 Ammonia • )

By formula: (H₄N⁺ • 2H₃N • H₂O) + H₃N = (H₄N⁺ • 3H₃N • H₂O)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.0	kcal/mol	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	34.3	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (H₄N⁺ • H₃N) + H₃N = (H₄N⁺ • 2H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17. ± 1.	kcal/mol	AVG	N/A	Average of 5 out of 8 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.9	cal/mol*K	HPMS	Tang and Castleman, 1975	gas phase; M
Δ_rS°	23.7	cal/mol*K	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rS°	24.8	cal/mol*K	DT	Long and Franklin, 1973	gas phase; M
Δ_rS°	26.8	cal/mol*K	PHPMS	Searles and Kebarle, 1968	gas phase; M
Δ_rS°	22.9	cal/mol*K	PHPMS	Payzant, Cunningham, et al., 1973	gas phase; typographical error in Δ_rH; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
9.7	296.	FA	Fehsenfeld and Ferguson, 1973	gas phase; DG>; M
10.1	296.	SAMS	Puckett and Teague, 1971	gas phase; M
5.5	400.	HPMS	Wincel, 1972	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (H₄N⁺ • 2H₃N) + H₃N = (H₄N⁺ • 3H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13. ± 5.	kcal/mol	AVG	N/A	Average of 6 out of 9 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25. ± 1.	cal/mol*K	AVG	N/A	Average of 4 out of 7 values; Individual data points

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
6.5	296.	FA	Fehsenfeld and Ferguson, 1973	gas phase; M
6.4	296.	SAMS	Puckett and Teague, 1971	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (H₄N⁺ • 3H₃N) + H₃N = (H₄N⁺ • 4H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	12.2 ± 0.9	kcal/mol	AVG	N/A	Average of 5 out of 10 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28. ± 2.	cal/mol*K	AVG	N/A	Average of 3 out of 7 values; Individual data points

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
3.4	296.	FA	Fehsenfeld and Ferguson, 1973	gas phase; M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (H₄N⁺ • 4H₃N) + H₃N = (H₄N⁺ • 5H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.0	kcal/mol	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rH°	7.5	kcal/mol	PHPMS	Searles and Kebarle, 1968	gas phase; M
Δ_rH°	7.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M
Δ_rH°	2.8	kcal/mol	TPEPICO	Kamke, Herrmann, et al., 1988	gas phase; M
Δ_rH°	9.6	kcal/mol	DT	Long and Franklin, 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.5	cal/mol*K	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rS°	25.	cal/mol*K	PHPMS	Searles and Kebarle, 1968	gas phase; M
Δ_rS°	32.	cal/mol*K	DT	Long and Franklin, 1973	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	0.5	kcal/mol	HPMS	Hogg, Haynes, et al., 1966	gas phase; M

( • 5 Ammonia ) + Ammonia = ( • 6 Ammonia )

By formula: (H₄N⁺ • 5H₃N) + H₃N = (H₄N⁺ • 6H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.5	kcal/mol	PHPMS	Arshadi and Futrell, 1974	gas phase; M
Δ_rH°	6.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.9	cal/mol*K	PHPMS	Arshadi and Futrell, 1974	gas phase; M

( • 6 Ammonia ) + Ammonia = ( • 7 Ammonia )

By formula: (H₄N⁺ • 6H₃N) + H₃N = (H₄N⁺ • 7H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 7 Ammonia ) + Ammonia = ( • 8 Ammonia )

By formula: (H₄N⁺ • 7H₃N) + H₃N = (H₄N⁺ • 8H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 8 Ammonia ) + Ammonia = ( • 9 Ammonia )

By formula: (H₄N⁺ • 8H₃N) + H₃N = (H₄N⁺ • 9H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 9 Ammonia ) + Ammonia = ( • 10 Ammonia )

By formula: (H₄N⁺ • 9H₃N) + H₃N = (H₄N⁺ • 10H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 10 Ammonia ) + Ammonia = ( • 11 Ammonia )

By formula: (H₄N⁺ • 10H₃N) + H₃N = (H₄N⁺ • 11H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 11 Ammonia ) + Ammonia = ( • 12 Ammonia )

By formula: (H₄N⁺ • 11H₃N) + H₃N = (H₄N⁺ • 12H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 12 Ammonia ) + Ammonia = ( • 13 Ammonia )

By formula: (H₄N⁺ • 12H₃N) + H₃N = (H₄N⁺ • 13H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 13 Ammonia ) + Ammonia = ( • 14 Ammonia )

By formula: (H₄N⁺ • 13H₃N) + H₃N = (H₄N⁺ • 14H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 14 Ammonia ) + Ammonia = ( • 15 Ammonia )

By formula: (H₄N⁺ • 14H₃N) + H₃N = (H₄N⁺ • 15H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

( • 15 Ammonia ) + Ammonia = ( • 16 Ammonia )

By formula: (H₄N⁺ • 15H₃N) + H₃N = (H₄N⁺ • 16H₃N)

Bond type: Hydrogen bond (positive ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.	kcal/mol	MKER	Wei, Tzeng, et al., 1990	gas phase; from graph; M

+ Ammonia = ( • Ammonia )

By formula: I^- + H₃N = (I^- • H₃N)

Bond type: Hydrogen bond (negative ion to hydride)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.40 ± 0.30	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B,M
Δ_rH°	7.4 ± 1.0	kcal/mol	TDAs	Caldwell, Masucci, et al., 1989	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.9	cal/mol*K	HPMS	Evans, Keesee, et al., 1987	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	1.20 ± 0.60	kcal/mol	TDAs	Evans, Keesee, et al., 1987	gas phase; B

+ Ammonia = ( • Ammonia )

By formula: K⁺ + H₃N = (K⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	20.1	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Δ_rH°	17.8	kcal/mol	HPMS	Davidson and Kebarle, 1976	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.0	cal/mol*K	HPMS	Castleman, 1978	gas phase; M
Δ_rS°	28.0	cal/mol*K	HPMS	Davidson and Kebarle, 1976	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (K⁺ • H₃N) + H₃N = (K⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.3	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.8	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (K⁺ • 2H₃N) + H₃N = (K⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.5	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.7	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (K⁺ • 3H₃N) + H₃N = (K⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.6	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.4	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Li⁺ + H₃N = (Li⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	39.1	kcal/mol	ICR	Woodin and Beauchamp, 1978	gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M
Δ_rH°	38.5	kcal/mol	ICR	Staley and Beauchamp, 1975	gas phase; switching reaction(Li+)H2O, from graph; Dzidic and Kebarle, 1970 extrapolated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.	cal/mol*K	N/A	Woodin and Beauchamp, 1978	gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	32.1	kcal/mol	ICR	Woodin and Beauchamp, 1978	gas phase; switching reaction(Li+)H2O, Entropy change calculated or estimated; Dzidic and Kebarle, 1970 interpolated; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Li⁺ • H₃N) + H₃N = (Li⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	33.1	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	29.7	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Li⁺ • 2H₃N) + H₃N = (Li⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	21.0	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.3	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Li⁺ • 3H₃N) + H₃N = (Li⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.5	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	32.6	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (Li⁺ • 4H₃N) + H₃N = (Li⁺ • 5H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.1	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.0	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 5 Ammonia ) + Ammonia = ( • 6 Ammonia )

By formula: (Li⁺ • 5H₃N) + H₃N = (Li⁺ • 6H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	9.3	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.3	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Mg⁺ + H₃N = (Mg⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	36.8 ± 2.8	kcal/mol	CIDT	Andersen, Muntean, et al., 2000	RCD

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Mg⁺ • H₃N) + H₃N = (Mg⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	29.2 ± 1.6	kcal/mol	CIDT	Andersen, Muntean, et al., 2000	RCD

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Mg⁺ • 2H₃N) + H₃N = (Mg⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	22.8 ± 2.1	kcal/mol	CIDT	Andersen, Muntean, et al., 2000	RCD

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Mg⁺ • 3H₃N) + H₃N = (Mg⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.4 ± 2.5	kcal/mol	CIDT	Andersen, Muntean, et al., 2000	RCD

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (Mg⁺ • 4H₃N) + H₃N = (Mg⁺ • 5H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.3 ± 2.8	kcal/mol	CIDT	Andersen, Muntean, et al., 2000	5th ligand is NH3; RCD

+ Ammonia = ( • Ammonia )

By formula: Mn⁺ + H₃N = (Mn⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	35.1 ± 1.9	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	36.9	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Mn⁺ • H₃N) + H₃N = (Mn⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	36.3 ± 2.9	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	34.1	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Mn⁺ • 2H₃N) + H₃N = (Mn⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.3 ± 2.2	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	11.8	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Mn⁺ • 3H₃N) + H₃N = (Mn⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.6 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

+ Ammonia = H₃N₂O^-

By formula: NO^- + H₃N = H₃N₂O^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.40	kcal/mol	N/A	Hendricks, de Clercq, et al., 2002	gas phase; B

+ Ammonia = ( • Ammonia )

By formula: Na⁺ + H₃N = (Na⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	24.4 ± 1.3	kcal/mol	CIDC	Amicangelo and Armentrout, 2001	Anchor NH3=24.41; RCD
Δ_rH°	24.4 ± 1.3	kcal/mol	CIDT	Armentrout and Rodgers, 2000	RCD
Δ_rH°	25.6 ± 0.2	kcal/mol	HPMS	Hoyau, Norrman, et al., 1999	RCD
Δ_rH°	29.1	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21800.	cal/mol*K	HPMS	Hoyau, Norrman, et al., 1999	RCD
Δ_rS°	25.7	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
18.6	298.	IMRE	McMahon and Ohanessian, 2000	Anchor alanine=39.89; RCD

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Na⁺ • H₃N) + H₃N = (Na⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	22. ± 1.	kcal/mol	AVG	N/A	Average of 6 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.1	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Na⁺ • 2H₃N) + H₃N = (Na⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	17.1	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.0	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Na⁺ • 3H₃N) + H₃N = (Na⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	14.7	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	29.0	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (Na⁺ • 4H₃N) + H₃N = (Na⁺ • 5H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.7	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	29.8	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

( • 5 Ammonia ) + Ammonia = ( • 6 Ammonia )

By formula: (Na⁺ • 5H₃N) + H₃N = (Na⁺ • 6H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	9.7	kcal/mol	HPMS	Castleman, Holland, et al., 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	29.7	cal/mol*K	HPMS	Castleman, Holland, et al., 1978	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Ni⁺ + H₃N = (Ni⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	55.2 ± 3.8	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	51.2	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Ni⁺ • H₃N) + H₃N = (Ni⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	59.5 ± 3.1	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	55.1	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Ni⁺ • 2H₃N) + H₃N = (Ni⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	21.5 ± 1.9	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	17.8	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Ni⁺ • 3H₃N) + H₃N = (Ni⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.8 ± 1.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

+ Ammonia = ( • Ammonia )

By formula: Pb⁺ + H₃N = (Pb⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	28.3	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.6	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Pb⁺ • H₃N) + H₃N = (Pb⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	19.2	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.0	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Pb⁺ • 2H₃N) + H₃N = (Pb⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.0	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.4	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Pb⁺ • 3H₃N) + H₃N = (Pb⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.7	kcal/mol	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.3	cal/mol*K	HPMS	Guo and Castleman, 1991	gas phase; Δ_rS from graph; M

+ Ammonia = ( • Ammonia )

By formula: Rb⁺ + H₃N = (Rb⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	18.7	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.3	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Rb⁺ • H₃N) + H₃N = (Rb⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	15.2	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.6	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Rb⁺ • 2H₃N) + H₃N = (Rb⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.1	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.1	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Rb⁺ • 3H₃N) + H₃N = (Rb⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	11.4	kcal/mol	HPMS	Castleman, 1978	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	38.0	cal/mol*K	HPMS	Castleman, 1978	gas phase; M

( • 4 Ammonia ) + Ammonia = ( • 5 Ammonia )

By formula: (Rb⁺ • 4H₃N) + H₃N = (Rb⁺ • 5H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10.2	kcal/mol	HPMS	Castleman, 1978	gas phase; M

+ Ammonia = ( • Ammonia )

By formula: Ti⁺ + H₃N = (Ti⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	46.6 ± 1.7	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (Ti⁺ • H₃N) + H₃N = (Ti⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	41.8 ± 3.6	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (Ti⁺ • 2H₃N) + H₃N = (Ti⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	42.1 ± 3.6	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (Ti⁺ • 3H₃N) + H₃N = (Ti⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	37.3 ± 2.4	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD

+ Ammonia = ( • Ammonia )

By formula: V⁺ + H₃N = (V⁺ • H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	45.4 ± 2.6	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	51.9	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • Ammonia ) + Ammonia = ( • 2 Ammonia )

By formula: (V⁺ • H₃N) + H₃N = (V⁺ • 2H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	39.2 ± 2.2	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	45.0	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 2 Ammonia ) + Ammonia = ( • 3 Ammonia )

By formula: (V⁺ • 2H₃N) + H₃N = (V⁺ • 3H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	24.9 ± 2.6	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	22.6	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

( • 3 Ammonia ) + Ammonia = ( • 4 Ammonia )

By formula: (V⁺ • 3H₃N) + H₃N = (V⁺ • 4H₃N)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	22.7 ± 2.6	kcal/mol	CIDT	Walter and Armentrout, 1998	RCD
Δ_rH°	18.7	kcal/mol	CID	Marinelli and Squires, 1989	gas phase; M

IR Spectrum

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, Mass spectrum (electron ionization), Gas Chromatography, References, Notes

Data compiled by: Coblentz Society, Inc.

GAS (50 mmHg DILUTED TO A TOTAL PRESSURE OF 600 mmHg WITH N2); DOW KBr FOREPRISM; DIGITIZED BY NIST FROM HARD COPY (FROM TWO SEGMENTS); 4 cm^-1 resolution

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Mass spectrum (electron ionization)

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Gas Chromatography, References, Notes

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

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Owner	NIST Mass Spectrometry Data Center Collection (C) 2014 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.
NIST MS number	6

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Gas Chromatography

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, Ion clustering data, IR Spectrum, Mass spectrum (electron ionization), References, Notes

Data compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Kovats' RI, non-polar column, isothermal

View large format table.

Column type	Active phase	Temperature (C)	I	Reference	Comment
Packed	PMS-100	150.	118.	Anderson, Jurel, et al., 1973	He, Celite 545 (44-60 mesh); Column length: 3. m
Packed	PMS-100	180.	131.	Anderson, Jurel, et al., 1973	He, Celite 545 (44-60 mesh); Column length: 3. m

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Dibeler, V.H.; Walker, J.A.; Rosenstock, H.M., Mass spectrometric study of photoionization. V.Water and ammonia, J.Res. NBS, 1966, 70A, 459. [all data]

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Baumgartel, H.; Jochims, H.-W.; Ruhl, E.; Bock, H.; Dammel, R.; Minkwitz, J.; Nass, R., Photoelectron and photoionization mass spectra of the fluoramines NH₃-_nF_n¹, Inorg. Chem., 1989, 28, 943. [all data]

Bieri, Asbrink, et al., 1982
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Kimura, Katsumata, et al., 1981
Kimura, K.; Katsumata, S.; Achiba, Y.; Yamazaki, T.; Iwata, S., Ionization energies, Ab initio assignments, and valence electronic structure for 200 molecules in Handbook of HeI Photoelectron Spectra of Fundamental Organic Compounds, Japan Scientific Soc. Press, Tokyo, 1981. [all data]

Campbell, Liesegang, et al., 1979
Campbell, M.J.; Liesegang, J.; Riley, J.D.; Leckey, R.C.G.; Jenkin, J.G.; Poole, R.T., The electronic structure of the valence bands of solid NH₃ and H₂O studied by ultraviolet photoelectron spectroscopy, J. Electron Spectrosc. Relat. Phenom., 1979, 15, 83. [all data]

Daamen and Oskam, 1978
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Notes

Symbols used in this document:

AE	Appearance energy
IE (evaluated)	Recommended ionization energy
P_c	Critical pressure
P_triple	Triple point pressure
S°_{gas,1 bar}	Entropy of gas at standard conditions (1 bar)
T	Temperature
T_c	Critical temperature
T_fus	Fusion (melting) point
Δ_fH°_gas	Enthalpy of formation of gas at standard conditions
Δ_rG°	Free energy of reaction at standard conditions
Δ_rH°	Enthalpy of reaction at standard conditions
Δ_rS°	Entropy of reaction at standard conditions
Δ_subH	Enthalpy of sublimation
Δ_vapH	Enthalpy of vaporization

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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Ammonia

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Gas phase thermochemistry data

Gas Phase Heat Capacity (Shomate Equation)

Phase change data

Enthalpy of vaporization

Antoine Equation Parameters

Enthalpy of sublimation

Reaction thermochemistry data

Reactions 1 to 50

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Gas phase ion energetics data

Ionization energy determinations

Appearance energy determinations

De-protonation reactions

Ion clustering data

Clustering reactions

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

Free energy of reaction

IR Spectrum

Mass spectrum (electron ionization)

Spectrum

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Additional Data

Gas Chromatography

Kovats' RI, non-polar column, isothermal

References

Notes