Nitrous oxide

Formula: N₂O
Molecular weight: 44.0128
IUPAC Standard InChI: InChI=1S/N2O/c1-2-3
IUPAC Standard InChIKey: GQPLMRYTRLFLPF-UHFFFAOYSA-N
CAS Registry Number: 10024-97-2
Chemical structure:
This structure is also available as a 2d Mol file or as a computed 3d SD file
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Other names: Nitrogen oxide (N2O); Dinitrogen monoxide; Dinitrogen oxide; Laughing gas; N2O; Factitious air; Hyponitrous acid anhydride; Nitrogen oxide; UN 1070; UN 2201; Nitrogen monoxide; Nitral
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Other data available:
- Gas phase thermochemistry data
- Phase change data
- Reaction thermochemistry data: reactions 51 to 83
- Henry's Law data
- Ion clustering data
- IR Spectrum
- Mass spectrum (electron ionization)
- Gas Chromatography
- Fluid Properties
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Reaction thermochemistry data

Go To: Top, Gas phase ion energetics data, References, Notes

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

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Reactions 1 to 50

+ Nitrous oxide = ( • )

By formula: NO^- + N₂O = (NO^- • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	10. ± 30.	kcal/mol	AVG	N/A	Average of 6 values; Individual data points
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	18.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rS°	14.9	cal/mol*K	DT	Illies, 1988	gas phase; Δ_rH(0 K)=7.70 kcal/mol; M

NO₂⁺ + Nitrous oxide = (NO₂⁺ • )

By formula: NO₂⁺ + N₂O = (NO₂⁺ • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	14.1	kcal/mol	EI	Cameron, Aitken, et al., 1994	gas phase; M
Δ_rH°	17.4	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rH°	13.1 ± 0.8	kcal/mol	DT	Illies, 1988	gas phase; Δ_rH(0 K)=13.3 kcal/mol; M
Δ_rH°	13.1	kcal/mol	PI	Linn and Ng, 1981	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rS°	12.4	cal/mol*K	DT	Illies, 1988	gas phase; Δ_rH(0 K)=13.3 kcal/mol; M

+ Nitrous oxide = ( • )

By formula: O₂⁺ + N₂O = (O₂⁺ • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	13.4	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rH°	10.7 ± 0.4	kcal/mol	DT	Illies, 1988	gas phase; Δ_rH(0 K)=10.8 kcal/mol; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rS°	15.3	cal/mol*K	DT	Illies, 1988	gas phase; Δ_rH(0 K)=10.8 kcal/mol; M

Free energy of reaction

Δ_rG° (kcal/mol)	T (K)	Method	Reference	Comment
8.9	200.	FA	Adams and Bohme, 1970	gas phase; switching reaction(O2+)O2; M

( • 2 Nitrous oxide ) + = ( • 3)

By formula: (I^- • 2N₂O) + N₂O = (I^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.7 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B
Δ_rH°	3.2	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	15.	cal/mol*K	N/A	Hiraoka, Aruga, et al., 1993	gas phase; Entropy change calculated or estimated; M

( • Nitrous oxide ) + = ( • 2)

By formula: (NO^- • N₂O) + N₂O = (NO^- • 2N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.90 ± 0.90	kcal/mol	N/A	Hendricks, de Clercq, et al., 2002	gas phase; B
Δ_rH°	4.60	kcal/mol	N/A	Coe, Snodgrass, et al., 1987	gas phase; B
Δ_rH°	5.6	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Δ_rH°	6.	kcal/mol	PES	Coe, Snodgrass, et al., 1986	gas phase; D(N2O)2 not accounted for; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.0 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 2 Nitrous oxide ) + = ( • 3)

By formula: (NO^- • 2N₂O) + N₂O = (NO^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.20 ± 0.90	kcal/mol	N/A	Hendricks, de Clercq, et al., 2002	gas phase; B
Δ_rH°	5.1	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rS°	21.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.2 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • Nitrous oxide ) + = ( • 2)

By formula: (I^- • N₂O) + N₂O = (I^- • 2N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.9 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B
Δ_rH°	3.3 ± 0.3	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	14.2	cal/mol*K	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M

+ Nitrous oxide = ( • )

By formula: I^- + N₂O = (I^- • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.7 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B
Δ_rH°	3.8 ± 0.3	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	14.1	cal/mol*K	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M

HN₂O⁺ + Nitrous oxide = (HN₂O⁺ • )

By formula: HN₂O⁺ + N₂O = (HN₂O⁺ • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	16.7	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rH°	20.6	kcal/mol	PHPMS	Szulejko and McMahon, 1992	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Δ_rS°	31.5	cal/mol*K	PHPMS	Szulejko and McMahon, 1992	gas phase; M

( • 2 Nitrous oxide ) + = ( • 3)

By formula: (O₂^- • 2N₂O) + N₂O = (O₂^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.40 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-0.8 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 3 Nitrous oxide ) + = ( • 4)

By formula: (O₂^- • 3N₂O) + N₂O = (O₂^- • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.70 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.5 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 4 Nitrous oxide ) + = ( • 5)

By formula: (O₂^- • 4N₂O) + N₂O = (O₂^- • 5N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.30 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.9 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 5 Nitrous oxide ) + = ( • 6)

By formula: (O₂^- • 5N₂O) + N₂O = (O₂^- • 6N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.00 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-2.2 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

(O^- • 2 Nitrous oxide ) + = (O^- • 3)

By formula: (O^- • 2N₂O) + N₂O = (O^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.40 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-0.9 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

(O^- • 3 Nitrous oxide ) + = (O^- • 4)

By formula: (O^- • 3N₂O) + N₂O = (O^- • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.20 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-2.0 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

(O^- • 4 Nitrous oxide ) + = (O^- • 5)

By formula: (O^- • 4N₂O) + N₂O = (O^- • 5N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.20 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	25.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-2.3 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

(O^- • 5 Nitrous oxide ) + = (O^- • 6)

By formula: (O^- • 5N₂O) + N₂O = (O^- • 6N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.10 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	26.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-2.7 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

(O^- • 6 Nitrous oxide ) + = (O^- • 7)

By formula: (O^- • 6N₂O) + N₂O = (O^- • 7N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.10 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	28.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-3.3 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

(O^- • Nitrous oxide ) + = (O^- • 2)

By formula: (O^- • N₂O) + N₂O = (O^- • 2N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.40 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	19.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-0.3 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • Nitrous oxide ) + = ( • 2)

By formula: (O₂^- • N₂O) + N₂O = (O₂^- • 2N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.70 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	0.6 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

+ Nitrous oxide = ( • )

By formula: O₂^- + N₂O = (O₂^- • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	<13.60	kcal/mol	IMRB	Adams and Bohme, 1970	gas phase; N₂O..O₂^- + O₂ -> O₄^- + N₂O; B
Δ_rH°	8.8	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	27.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M

( • 3 Nitrous oxide ) + = ( • 4)

By formula: (NO^- • 3N₂O) + N₂O = (NO^- • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.00 ± 0.90	kcal/mol	N/A	Hendricks, de Clercq, et al., 2002	gas phase; B
Δ_rH°	4.5	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.2 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 4 Nitrous oxide ) + = ( • 5)

By formula: (NO^- • 4N₂O) + N₂O = (NO^- • 5N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.20 ± 0.90	kcal/mol	N/A	Hendricks, de Clercq, et al., 2002	gas phase; B
Δ_rH°	4.5	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.5 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 3 Nitrous oxide ) + = ( • 4)

By formula: (H₃O⁺ • 3N₂O) + N₂O = (H₃O⁺ • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.2	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	21.	cal/mol*K	N/A	Hiraoka, Fujimaki, et al., 1994	gas phase; Entropy change calculated or estimated; M

(NO₂⁺ • 5 Nitrous oxide ) + = (NO₂⁺ • 6)

By formula: (NO₂⁺ • 5N₂O) + N₂O = (NO₂⁺ • 6N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	3.9	kcal/mol	PHPMS	Hiraoka, Fujimaki, 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	Hiraoka, Fujimaki, et al., 1994	gas phase; Entropy change calculated or estimated; M

(HN₂O⁺ • 5 Nitrous oxide ) + = (HN₂O⁺ • 6)

By formula: (HN₂O⁺ • 5N₂O) + N₂O = (HN₂O⁺ • 6N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.8	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	30.	cal/mol*K	N/A	Hiraoka, Fujimaki, et al., 1994	gas phase; Entropy change calculated or estimated; M

( • 4 Nitrous oxide ) + = ( • 5)

By formula: (Cl^- • 4N₂O) + N₂O = (Cl^- • 5N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.8	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	22.	cal/mol*K	N/A	Hiraoka, Aruga, et al., 1993	gas phase; Entropy change calculated or estimated; M

( • 6 Nitrous oxide ) + = ( • 7)

By formula: (F^- • 6N₂O) + N₂O = (F^- • 7N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	3.3	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; Entropy change calculated or estimated; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.	cal/mol*K	N/A	Hiraoka, Aruga, et al., 1993	gas phase; Entropy change calculated or estimated; M

(NO₂⁺ • 2 Nitrous oxide ) + = (NO₂⁺ • 3)

By formula: (NO₂⁺ • 2N₂O) + N₂O = (NO₂⁺ • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.8	kcal/mol	EI	Cameron, Aitken, et al., 1994	gas phase; M
Δ_rH°	5.6	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	24.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M

(NO₂⁺ • Nitrous oxide ) + = (NO₂⁺ • 2)

By formula: (NO₂⁺ • N₂O) + N₂O = (NO₂⁺ • 2N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.1	kcal/mol	EI	Cameron, Aitken, et al., 1994	gas phase; M
Δ_rH°	5.7	kcal/mol	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	18.	cal/mol*K	PHPMS	Hiraoka, Fujimaki, et al., 1994	gas phase; M

( • 5 Nitrous oxide ) + = ( • 6)

By formula: (NO^- • 5N₂O) + N₂O = (NO^- • 6N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.40 ± 0.20	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-1.9 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

( • 6 Nitrous oxide ) + = ( • 7)

By formula: (NO^- • 6N₂O) + N₂O = (NO^- • 7N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.20 ± 0.30	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B,M,M
Quantity	Value	Units	Method	Reference	Comment
Δ_rG°	-2.7 ± 1.0	kcal/mol	TDAs	Hiraoka, Fujimaki, et al., 1994, 2	gas phase; B

+ Nitrous oxide = ( • )

By formula: CH₃⁺ + N₂O = (CH₃⁺ • N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	52.9	kcal/mol	PHPMS	McMahon, Heinis, et al., 1988	gas phase; switching reaction(CH3+)N2, Entropy change calculated or estimated, uses MCA(N2) = 48.3 kcal/mol; Foster, Williamson, et al., 1974; M

( • 10 Nitrous oxide ) + = ( • 11)

By formula: (I^- • 10N₂O) + N₂O = (I^- • 11N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	1.0 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 11 Nitrous oxide ) + = ( • 12)

By formula: (I^- • 11N₂O) + N₂O = (I^- • 12N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	1.3 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 9 Nitrous oxide ) + = ( • 10)

By formula: (I^- • 9N₂O) + N₂O = (I^- • 10N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	1.8 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 3 Nitrous oxide ) + = ( • 4)

By formula: (I^- • 3N₂O) + N₂O = (I^- • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.8 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 4 Nitrous oxide ) + = ( • 5)

By formula: (I^- • 4N₂O) + N₂O = (I^- • 5N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.7 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 5 Nitrous oxide ) + = ( • 6)

By formula: (I^- • 5N₂O) + N₂O = (I^- • 6N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.3 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 6 Nitrous oxide ) + = ( • 7)

By formula: (I^- • 6N₂O) + N₂O = (I^- • 7N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.2 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 7 Nitrous oxide ) + = ( • 8)

By formula: (I^- • 7N₂O) + N₂O = (I^- • 8N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.1 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

( • 8 Nitrous oxide ) + = ( • 9)

By formula: (I^- • 8N₂O) + N₂O = (I^- • 9N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	2.4 ± 2.0	kcal/mol	PDis	Arnold, Bradforth, et al., 1995	gas phase; EA given is Vertical Detachment Energy. Affinity: difference between successive EAs in (Y); B

(N₂O₂^- • 4294967295 Nitrous oxide ) + = N₂O₂^-

By formula: (N₂O₂^- • 4294967295N₂O) + N₂O = N₂O₂^-

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	23.1 ± 1.2	kcal/mol	N/A	Li and Continetti, 2002	gas phase; B
Δ_rH°	32.30 ± 0.70	kcal/mol	LPD	Osboen, Leahy, et al., 1996	gas phase; Affinity at 0 K; B

(HO^- • 3 Nitrous oxide ) + = (HO^- • 4)

By formula: (HO^- • 3N₂O) + N₂O = (HO^- • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	>7. ± 33.	kcal/mol	N/A	Kim, Wenthold, et al., 1998	gas phase; Vertical Detachment Energy: 2.981 eV. Affinity is EA difference with next lower +0.08 eV f; B

(HO^- • 4 Nitrous oxide ) + = (HO^- • 5)

By formula: (HO^- • 4N₂O) + N₂O = (HO^- • 5N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	>5. ± 54.	kcal/mol	N/A	Kim, Wenthold, et al., 1998	gas phase; Vertical Detachment Energy: 3.146 eV. Affinity is EA difference with next lower +0.08 eV f; B

(HO^- • 2 Nitrous oxide ) + = (HO^- • 3)

By formula: (HO^- • 2N₂O) + N₂O = (HO^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	6.90	kcal/mol	N/A	Kim, Wenthold, et al., 1998	gas phase; Vertical Detachment Energy: 2.761 eV. Affinity is EA difference with next lower +0.08 eV f; B

(HO^- • Nitrous oxide ) + = (HO^- • 2)

By formula: (HO^- • N₂O) + N₂O = (HO^- • 2N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	7.80	kcal/mol	N/A	Kim, Wenthold, et al., 1998	gas phase; Vertical Detachment Energy: 2.485 eV. Affinity is EA difference with next lower +0.08 eV f; B

( • 2 Nitrous oxide ) + = ( • 3)

By formula: (Cl^- • 2N₂O) + N₂O = (Cl^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	5.1 ± 0.3	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.0	cal/mol*K	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M

( • 3 Nitrous oxide ) + = ( • 4)

By formula: (Cl^- • 3N₂O) + N₂O = (Cl^- • 4N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	4.9 ± 0.3	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	20.9	cal/mol*K	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M

( • 2 Nitrous oxide ) + = ( • 3)

By formula: (F^- • 2N₂O) + N₂O = (F^- • 3N₂O)

Quantity	Value	Units	Method	Reference	Comment
Δ_rH°	8.4 ± 0.3	kcal/mol	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M
Quantity	Value	Units	Method	Reference	Comment
Δ_rS°	23.6	cal/mol*K	PHPMS	Hiraoka, Aruga, et al., 1993	gas phase; M

Gas phase ion energetics data

Go To: Top, Reaction thermochemistry data, 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:
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron
LBLHLM - Sharon G. Lias, John E. Bartmess, Joel F. Liebman, John L. Holmes, Rhoda D. Levin, and W. Gary Mallard
B - John E. Bartmess

View reactions leading to N₂O⁺ (ion structure unspecified)

Quantity	Value	Units	Method	Reference	Comment
IE (evaluated)	12.889 ± 0.004	eV	N/A	N/A	L
Quantity	Value	Units	Method	Reference	Comment
Proton affinity (review)	131.4	kcal/mol	N/A	Hunter and Lias, 1998	at N; HL
Proton affinity (review)	137.5	kcal/mol	N/A	Hunter and Lias, 1998	at O; HL
Quantity	Value	Units	Method	Reference	Comment
Gas basicity	125.1	kcal/mol	N/A	Hunter and Lias, 1998	at N; HL
Gas basicity	131.1	kcal/mol	N/A	Hunter and Lias, 1998	at O; HL

Electron affinity determinations

EA (eV)	Method	Reference	Comment
0.22 ± 0.10	CIDT	Tiernan and Wu, 1978	B
>-0.15 ± 0.10	NBIE	Nalley, Compton, et al., 1973	B
0.27 ± 0.17	ECD	Wentworth, Chen, et al., 1971	B
<0.76 ± 0.10	LPES	Coe, Snodgrass, et al., 1986	Vertical Detachment Energy: ca. 1.5 eV. Anion bent, with little Franck-Condon overlap; B

Ionization energy determinations

IE (eV)	Method	Reference	Comment
12.89	PE	Kimura, Katsumata, et al., 1981	LLK
12. ± 1.	PI	Hitchcock, Brion, et al., 1980	LLK
12.91 ± 0.03	EI	Sahini, Constantin, et al., 1978	LLK
12.886 ± 0.002	PE	Berkowitz and Eland, 1977	LLK
12.88 ± 0.005	PI	Coppens, Smets, et al., 1974	LLK
12.89 ± 0.005	PI	Coppens, Smets, et al., 1974	LLK
12.90	PE	Eland, 1973	LLK
12.891 ± 0.008	PE	Collin and Natalis, 1969	RDSH
12.893 ± 0.005	PE	Brundle and Turner, 1969	RDSH
12.89	PI	Cook, Metzger, et al., 1968	RDSH
12.888 ± 0.007	PI	Dibeler and Walker, 1967	RDSH
12.8 ± 0.05	EI	Carette, 1967	RDSH
12.882 ± 0.008	PI	Nicholson, 1965	RDSH
12.894	S	Tanaka, Jursa, et al., 1960	RDSH
12.89	PE	Potts and Williams, 1974	Vertical value; LLK

Appearance energy determinations

Ion	AE (eV)	Other Products	Method	Reference	Comment
N⁺	20. ± 1.	NO	PI	Hitchcock, Brion, et al., 1980	LLK
N⁺	19.494	NO	PE	Berkowitz and Eland, 1977	LLK
N⁺	20.06	NO	PE	Dibeler, Walker, et al., 1967	RDSH
NO⁺	15.3 ± 0.1	N	EI	Olivier, Locht, et al., 1982	LBLHLM
NO⁺	16. ± 1.	N	PI	Hitchcock, Brion, et al., 1980	LLK
NO⁺	16.53 ± 0.01	N	PI	Coppens, Smets, et al., 1974	LLK
NO⁺	15.01	N	PI	Coppens, Smets, et al., 1974	LLK
NO⁺	17.73 ± 0.01	N	PI	Coppens, Smets, et al., 1974	LLK
NO⁺	14.3 ± 0.3	N(4Sø)	EI	Coleman, Delderfield, et al., 1969	RDSH
NO⁺	17.74	N(2Pø)?	PI	Dibeler and Walker, 1967	RDSH
NO⁺	16.53	N(2Dø)?	PI	Dibeler and Walker, 1967	RDSH
NO⁺	15.01	N(4Sø)	PI	Dibeler and Walker, 1967	RDSH
NO⁺	13.75 ± 0.10	N(4Sø)	EI	Curran and Fox, 1961	RDSH
N₂⁺	17.3 ± 0.2	O	EI	Olivier, Locht, et al., 1982	LBLHLM
N₂⁺	18. ± 1.	O	PI	Hitchcock, Brion, et al., 1980	LLK
N₂⁺	17.29	O	PI	Dibeler, 1967	RDSH
O⁺	15. ± 1.	N₂	PI	Hitchcock, Brion, et al., 1980	LLK
O⁺	15.31	N₂	PI	Dibeler, Walker, et al., 1967	RDSH

References

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, Notes

Hiraoka, Fujimaki, et al., 1994
Hiraoka, K.; Fujimaki, S.; Aruga, K.; Sato, T.; Yamabe, S., Gas-Phase Solavtion of NO+, O2+, N2O+, and H3O+ with N2O, J. Chem. Phys., 1994, 101, 5, 4073, https://doi.org/10.1063/1.467524 . [all data]

Illies, 1988
Illies, A.J., Thermochemistry of the Gas - Phase Ion - Molecule Clustering of CO2+CO2, SO2+CO2, N2O+N2O, O2+CO2, NO+CO2 and NO+N2O: Description of a New Hybrid Drift Tube/Ion Source with Coaxial Electron Beam and Ion Exit Apertures, J. Phys. Chem., 1988, 92, 10, 2889, https://doi.org/10.1021/j100321a037 . [all data]

Cameron, Aitken, et al., 1994
Cameron, B.R.; Aitken, C.G.; Harland, P.W., Appearence Energies of Small Cluster Ions and their Fragments, J. Chem. Soc. Faraday Trans., 1994, 90, 7, 935, https://doi.org/10.1039/ft9949000935 . [all data]

Linn and Ng, 1981
Linn, S.H.; Ng, C.Y., Photoionization Study of CO2, N2O Dimers and Clusters, J. Chem. Phys., 1981, 75, 10, 4921, https://doi.org/10.1063/1.441931 . [all data]

Adams and Bohme, 1970
Adams, N.G.; Bohme, D., Flowing Afterglow Studies of Formation and Reactions of Cluster Ions of O₂⁺, O₂^-, and O^-, J. Chem. Phys., 1970, 52, 6, 3133, https://doi.org/10.1063/1.1673449 . [all data]

Arnold, Bradforth, et al., 1995
Arnold, D.W.; Bradforth, S.E.; Kim, E.H.; Neumark, D.M., Study of I-(CO2)n, Br-(CO2)n, and I-(N2O)n clusters by anion photoelectron spectroscopy, J. Chem. Phys., 1995, 102, 9, 3510, https://doi.org/10.1063/1.468576 . [all data]

Hiraoka, Aruga, et al., 1993
Hiraoka, K.; Aruga, K.; Fujimaki, S.; Yamabe, S., Comparative Study of the Gas Phase Bond Strengths of CO2 and N2O with the Halide Ions, J. Am. Soc. Mass Spectrom., 1993, 4, 1, 58, https://doi.org/10.1016/1044-0305(93)85043-W . [all data]

Hendricks, de Clercq, et al., 2002
Hendricks, J.H.; de Clercq, H.L.; Freidhoff, C.B.; Arnold, S.T.; Eaton, J.G.; Fancher, C.; Lyapustina, S.A.; S., Anion solvation at the microscopic level: Photoelectron spectroscopy of the solvated anion clusters, NO-(Y)(n), where Y=Ar, Kr, Xe, N2O, H2S, NH3, H2O, and C2H4(OH)(2), J. Chem. Phys., 2002, 116, 18, 7926-7938, https://doi.org/10.1063/1.1457444 . [all data]

Coe, Snodgrass, et al., 1987
Coe, J.V.; Snodgrass, J.T.; Freidhoff, C.B.; McHugh, K.M.; Bowen, K.H., Photoelectron spectroscopy of the negative cluster ions, NO-(N₂O)n=1,2, J. Chem. Phys., 1987, 87, 4302. [all data]

Hiraoka, Fujimaki, et al., 1994, 2
Hiraoka, K.; Fujimaki, S.; Aruga, K.; Yamabe, S., Gas-phase clustering reactions of O2(-), NO-, and O- with N2O: Isomeric structures for (NO-N2O)(-), J. Phys. Chem., 1994, 98, 34, 8295, https://doi.org/10.1021/j100085a006 . [all data]

Coe, Snodgrass, et al., 1986
Coe, J.V.; Snodgrass, J.T.; Freidhoff, C.B.; McHugh, K.M.; Bowen, K.H., Negative ion photoelectron spectroscopy of N₂O^- and (N₂O)₂^-, Chem. Phys. Lett., 1986, 124, 274. [all data]

Szulejko and McMahon, 1992
Szulejko, J.; McMahon, T.B., personal communication, 1992. [all data]

McMahon, Heinis, et al., 1988
McMahon, T.; Heinis, T.; Nicol, G.; Hovey, J.K.; Kebarle, P., Methyl Cation Affinities, J. Am. Chem. Soc., 1988, 110, 23, 7591, https://doi.org/10.1021/ja00231a002 . [all data]

Foster, Williamson, et al., 1974
Foster, M.S.; Williamson, A.D.; Beauchamp, J.L., Photoionization mass spectrometry of trans-azomethane, Int. J. Mass Spectrom. Ion Phys., 1974, 15, 429. [all data]

Li and Continetti, 2002
Li, R.J.; Continetti, R.E., Studies of the excited state dynamics of N2O2 by dissociative photodetachment of N2O2-, J. Phys. Chem. A, 2002, 106, 7, 1183-1189, https://doi.org/10.1021/jp013330u . [all data]

Osboen, Leahy, et al., 1996
Osboen, D.L.; Leahy, D.J.; Cyr, D.R.; Neumark, D.M., Photodissociation Spectroscopy and Dynamics of the N2O2- Anion, J. Chem. Phys., 1996, 104, 13, 5026, https://doi.org/10.1063/1.471132 . [all data]

Kim, Wenthold, et al., 1998
Kim, J.B.; Wenthold, P.G.; Lineberger, W.C., Photoelectron spectroscopy of OH-(N2O)(n=1-5), J. Chem. Phys., 1998, 108, 3, 830-837, https://doi.org/10.1063/1.475447 . [all data]

Hunter and Lias, 1998
Hunter, E.P.; Lias, S.G., Evaluated Gas Phase Basicities and Proton Affinities of Molecules: An Update, J. Phys. Chem. Ref. Data, 1998, 27, 3, 413-656, https://doi.org/10.1063/1.556018 . [all data]

Tiernan and Wu, 1978
Tiernan, T.O.; Wu, R.L.C., Thermochemical Data for Molecular Negative Ions from Collisional Dissociation Thresholds, Adv. Mass Spectrom., 1978, 7A, 136. [all data]

Nalley, Compton, et al., 1973
Nalley, S.J.; Compton, R.N.; Schweinler, H.C.; Anderson, V.E., Molecular electron affinities from collisional ionization of cesium. I. NO, NO₂, and N₂O, J. Chem. Phys., 1973, 59, 4125. [all data]

Wentworth, Chen, et al., 1971
Wentworth, W.E.; Chen, E.; Freeman, R., Thermal electron attachment to N₂O, J. Chem. Phys., 1971, 55, 2075. [all data]

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]

Hitchcock, Brion, et al., 1980
Hitchcock, A.P.; Brion, C.E.; Van der Wiel, M.J., Absolute oscillator strengths for valence-shell ionic photofragmentation of N₂O and CO₂(8-75 eV), Chem. Phys., 1980, 45, 461. [all data]

Sahini, Constantin, et al., 1978
Sahini, V.E.; Constantin, V.; Serban, I., Determination of ionization potentials using a MI-1305 mass spectrometer, Rev. Roum. Chim., 1978, 23, 479. [all data]

Berkowitz and Eland, 1977
Berkowitz, J.; Eland, J.H.D., Photoionization of N₂O: Mechanisms of photoionization and ion dissociation, J. Chem. Phys., 1977, 67, 2740. [all data]

Coppens, Smets, et al., 1974
Coppens, P.; Smets, J.; Fishel, M.G.; Drowart, J., Mass spectrometric study of the photoionization of nitrous oxide in the wavelength interval 1000-600 A, Int. J. Mass Spectrom. Ion Phys., 1974, 14, 57. [all data]

Eland, 1973
Eland, J.H.D., Predissociation of N₂O⁺ and COS⁺ ions studied by photoelectronphotoion coincidence spectroscopy, Int. J. Mass Spectrom. Ion Phys., 1973, 12, 389. [all data]

Collin and Natalis, 1969
Collin, J.E.; Natalis, P., Determination des etats electroniques et des niveaux de vibration des ions moleculaires par spectroscopie de photoelectrons, Bull. Classe Sci. Acad. Roy. Belg., 1969, 55, 352. [all data]

Brundle and Turner, 1969
Brundle, C.R.; Turner, D.W., Studies on the photoionisation of the linear triatomic molecules: N₂O, COS, CS₂ and CO₂ using high-resolution photoelectron spectroscopy, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 195. [all data]

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Cook, G.R.; Metzger, P.H.; Ogawa, M., Photoionization and absorption coefficients of N₂O, J. Opt. Soc. Am., 1968, 58, 129. [all data]

Dibeler and Walker, 1967
Dibeler, V.H.; Walker, J.A., Mass spectrometric study of the photoionization of small polyatomic molecules, Advan. Mass Spectrom., 1967, 4, 767. [all data]

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Carette, J.-D., Ionisation par impact electronique de CO₂ et N₂O, Can. J. Phys., 1967, 45, 2931. [all data]

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Nicholson, A.J.C., Photoionization-efficiency curves. II. False and genuine structure, J. Chem. Phys., 1965, 43, 1171. [all data]

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Tanaka, Y.; Jursa, A.S.; LeBlanc, F.J., Higher ionization potentials of linear triatomic molecules. II. CS₂, COS, and N₂O, J. Chem. Phys., 1960, 32, 1205. [all data]

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Potts, A.W.; Williams, T.A., The observation of "forbidden" transitions in He II photoelectron spectra, J. Electron Spectrosc. Relat. Phenom., 1974, 3, 3. [all data]

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Dibeler, V.H.; Walker, J.A.; Liston, S.K., Mass spectrometric study of photoionization. VII.Nitrogen dioxide and nitrous oxide, J.Res. NBS, 1967, 71A, 371. [all data]

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Olivier, J.L.; Locht, R.; Momigny, J., A dissociative electroionization study of nitrous oxide. The No and N₂ dissociation channels, Chem. Phys., 1982, 68, 201. [all data]

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Coleman, R.J.; Delderfield, J.S.; Reuben, B.G., The gas-phase decomposition of the nitrous oxide ion, Intern. J. Mass Spectrom. Ion Phys., 1969, 2, 25. [all data]

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Curran, R.K.; Fox, R.E., Mass spectrometer investigation of ionization of N₂O by electron impact, J. Chem. Phys., 1961, 34, 1590. [all data]

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Notes

Go To: Top, Reaction thermochemistry data, Gas phase ion energetics data, References

Symbols used in this document:

AE	Appearance energy
EA	Electron affinity
IE (evaluated)	Recommended ionization energy
T	Temperature
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

Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
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