Hydrogen

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Gas phase thermochemistry data

Go To: Top, Phase change data, Gas phase ion energetics data, Ion clustering data, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Quantity Value Units Method Reference Comment
gas,1 bar130.680 ± 0.003J/mol*KReviewCox, Wagman, et al., 1984CODATA Review value
gas,1 bar130.68J/mol*KReviewChase, 1998Data last reviewed in March, 1977

Gas Phase Heat Capacity (Shomate Equation)

Cp° = 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
    Cp = heat capacity (J/mol*K)
    H° = standard enthalpy (kJ/mol)
    S° = standard entropy (J/mol*K)
    t = temperature (K) / 1000.

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View table.

Temperature (K) 298. to 1000.1000. to 2500.2500. to 6000.
A 33.06617818.56308343.413560
B -11.36341712.257357-4.293079
C 11.432816-2.8597861.272428
D -2.7728740.268238-0.096876
E -0.1585581.977990-20.533862
F -9.980797-1.147438-38.515158
G 172.707974156.288133162.081354
H 0.00.00.0
ReferenceChase, 1998Chase, 1998Chase, 1998
Comment Data last reviewed in March, 1977; New parameter fit October 2001 Data last reviewed in March, 1977; New parameter fit October 2001 Data last reviewed in March, 1977; New parameter fit October 2001

Phase change data

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

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled as indicated in comments:
TRC - Thermodynamics Research Center, NIST Boulder Laboratories, Chris Muzny director

Quantity Value Units Method Reference Comment
Ttriple0.KN/ARoder, Childs, et al., 1973TRC
Ttriple13.95KN/AClusius and Weigand, 1940Uncertainty assigned by TRC = 0.06 K; see property X for dP/dT for c-l equil.; TRC
Ttriple13.96KN/AHenning and Otto, 1936Uncertainty assigned by TRC = 0.05 K; temperature measured with He gas thermometer; TRC
Quantity Value Units Method Reference Comment
Ptriple0.barN/ARoder, Childs, et al., 1973TRC
Ptriple0.0721barN/AHenning and Otto, 1936Uncertainty assigned by TRC = 0.0004 bar; TRC
Quantity Value Units Method Reference Comment
Tc33.18KN/AOnnes, Crommelin, et al., 1917Uncertainty assigned by TRC = 0.2 K; derived from P-V-T measurements; TRC
Quantity Value Units Method Reference Comment
Pc13.00barN/AOnnes, Crommelin, et al., 1917Uncertainty assigned by TRC = 0.0119 bar; derived from vapor pressure extrapolated to Tc; TRC
Quantity Value Units Method Reference Comment
ρc15.4mol/lN/AOnnes, Crommelin, et al., 1917Uncertainty assigned by TRC = 2. mol/l; by extrapolation of rectilinear diameter to Tc; TRC

Antoine Equation Parameters

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

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Temperature (K) A B C Reference Comment
21.01 to 32.273.5431499.3957.726van Itterbeek, Verbeke, et al., 1964Coefficents calculated by NIST from author's data.

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:


Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Phase change data, Ion clustering data, References, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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 H2+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)15.42593 ± 0.00005eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)422.3kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity394.7kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
15.425927EVALShiner, Gilligan, et al., 1993T = 0K; LL
15.425930EVALShiner, Gilligan, et al., 1993T = 0K; LL
15.425932 ± 0.000002SMcCormack, Gilligan, et al., 1989T = 0K; LL
15.429558 ± 0.00001LSGlab and Hessler, 1987T = 0K; LBLHLM
15.433174 ± 0.00001LSGlab and Hessler, 1987T = 0K; LBLHLM
15.425942 ± 0.00001LSGlab and Hessler, 1987T = 0K; LBLHLM
15.425932SEyler, Short, et al., 1986T = 0K; LBLHLM
15.425929SEyler, Short, et al., 1986T = 0K; LBLHLM
15.425930 ± 0.000027N/AEyler, Short, et al., 1986LBLHLM
15.5 ± 1.0SFarber, Srivastava, et al., 1982LBLHLM
15.98PEKimura, Katsumata, et al., 1981LLK
15.43PEBieri, Schmelzer, et al., 1980LLK
15.42589EVALHuber and Herzberg, 1979LLK
16. ± 1.EIFarber and Srivastava, 1977LLK
15.4PIRabalais, Debies, et al., 1974LLK
15.43PELee and Rabalais, 1974LLK
15.42589 ± 0.00005SHerzberg and Jungen, 1972LLK
15.4256 ± 0.0001STakezawa, 1970RDSH
15.38186 ± 0.00031PEAsbrink, 1970RDSH
15.44 ± 0.01EILossing and Semeluk, 1969RDSH
15.4256SHerzberg, 1969RDSH
15.431 ± 0.022TEVillarejo, 1968RDSH
15.439 ± 0.015PECollin and Natalis, 1968RDSH
15.43CICermak, 1968RDSH
15.37 ± 0.05EIKerwin, Marmet, et al., 1963RDSH
15.4269 ± 0.0016SBeutler and Junger, 1936RDSH

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
H+18.078 ± 0.003HPIPECOWeitzel, Mahnert, et al., 1994T = 0K; LL
H+18.0 ± 0.2HEICrowe and McConkey, 1973LLK
H+17.28 ± 0.16H-EILocht and Momigny, 1971LLK
H+17.3H-EICurran, LaboratoriesRDSH

De-protonation reactions

Hydrogen anion + Hydrogen cation = Hydrogen

By formula: H- + H+ = H2

Quantity Value Units Method Reference Comment
Δr1675.3kJ/molN/AShiell, Hu, et al., 2000gas phase; Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B
Δr1675.3kJ/molN/APratt, McCormack, et al., 1992gas phase; 399.46±0.01 kcal/mol at 0K; 0.94 correction, Gurvich, Veyts, et al.; B
Δr1675.3kJ/molD-EALykke, Murray, et al., 1991gas phase; Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B
Quantity Value Units Method Reference Comment
Δr1649.3 ± 0.42kJ/molH-TSShiell, Hu, et al., 2000gas phase; Given: 139714.8±1 cm-1 at 0K, or 399.465±0.003 kcal/mol; B
Δr1649.3kJ/molH-TSLykke, Murray, et al., 1991gas phase; Reported: 6082.99±0.15 cm-1, or 0.754195(18) eV; B

Ion clustering data

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

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Data compiled by: Michael M. Meot-Ner (Mautner) and Sharon G. Lias

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

Ar+ + Hydrogen = (Ar+ • Hydrogen)

By formula: Ar+ + H2 = (Ar+ • H2)

Quantity Value Units Method Reference Comment
Δr93.7kJ/molFAShul, Passarella, et al., 1987gas phase; switching reaction(Ar+)Ar, ΔrH>; Dehmer and Pratt, 1982

Formyl cation + Hydrogen = (Formyl cation • Hydrogen)

By formula: CHO+ + H2 = (CHO+ • H2)

Quantity Value Units Method Reference Comment
Δr16.kJ/molPHPMSHiraoka and Kebarle, 1975gas phase
Quantity Value Units Method Reference Comment
Δr85.8J/mol*KPHPMSHiraoka and Kebarle, 1975gas phase

CH5+ + Hydrogen = (CH5+ • Hydrogen)

By formula: CH5+ + H2 = (CH5+ • H2)

Quantity Value Units Method Reference Comment
Δr7.87 ± 0.42kJ/molPHPMSHiraoka, Kudaka, et al., 1991gas phase
Quantity Value Units Method Reference Comment
Δr50.6J/mol*KPHPMSHiraoka, Kudaka, et al., 1991gas phase

(CH5+ • Hydrogen) + Hydrogen = (CH5+ • 2Hydrogen)

By formula: (CH5+ • H2) + H2 = (CH5+ • 2H2)

Quantity Value Units Method Reference Comment
Δr7.45 ± 0.42kJ/molPHPMSHiraoka, Kudaka, et al., 1991gas phase
Quantity Value Units Method Reference Comment
Δr67.8J/mol*KPHPMSHiraoka, Kudaka, et al., 1991gas phase

(CH5+ • 2Hydrogen) + Hydrogen = (CH5+ • 3Hydrogen)

By formula: (CH5+ • 2H2) + H2 = (CH5+ • 3H2)

Quantity Value Units Method Reference Comment
Δr6.74 ± 0.42kJ/molPHPMSHiraoka, Kudaka, et al., 1991gas phase
Quantity Value Units Method Reference Comment
Δr94.6J/mol*KPHPMSHiraoka, Kudaka, et al., 1991gas phase

(CH5+ • 3Hydrogen) + Hydrogen = (CH5+ • 4Hydrogen)

By formula: (CH5+ • 3H2) + H2 = (CH5+ • 4H2)

Quantity Value Units Method Reference Comment
Δr6.57 ± 0.42kJ/molPHPMSHiraoka, Kudaka, et al., 1991gas phase
Quantity Value Units Method Reference Comment
Δr108.J/mol*KPHPMSHiraoka, Kudaka, et al., 1991gas phase

C3H7+ + Hydrogen = (C3H7+ • Hydrogen)

By formula: C3H7+ + H2 = (C3H7+ • H2)

Quantity Value Units Method Reference Comment
Δr10.kJ/molPHPMSHiraoka and Kebarle, 1976gas phase; Entropy change calculated or estimated, DG<, ΔrH<
Quantity Value Units Method Reference Comment
Δr84.J/mol*KN/AHiraoka and Kebarle, 1976gas phase; Entropy change calculated or estimated, DG<, ΔrH<

Free energy of reaction

ΔrG° (kJ/mol) T (K) Method Reference Comment
4.170.PHPMSHiraoka and Kebarle, 1976gas phase; Entropy change calculated or estimated, DG<, ΔrH<

(Cobalt ion (1+) • Methane) + Hydrogen = (Cobalt ion (1+) • Hydrogen • Methane)

By formula: (Co+ • CH4) + H2 = (Co+ • H2 • CH4)

Quantity Value Units Method Reference Comment
Δr95.8J/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+).2H2, ΔrS(440 K); Kemper, Bushnell, et al., 1993, 2

Enthalpy of reaction

ΔrH° (kJ/mol) T (K) Method Reference Comment
73. (+3.,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; switching reaction(Co+).2H2, ΔrS(440 K); Kemper, Bushnell, et al., 1993, 2

(Cobalt ion (1+) • Water) + Hydrogen = (Cobalt ion (1+) • Hydrogen • Water)

By formula: (Co+ • H2O) + H2 = (Co+ • H2 • H2O)

Quantity Value Units Method Reference Comment
Δr103.J/mol*KSIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(530 K)

Enthalpy of reaction

ΔrH° (kJ/mol) T (K) Method Reference Comment
83. (+3.,-0.) SIDTKemper, Bushnell, et al., 1993gas phase; ΔrS(530 K)

Cobalt ion (1+) + Hydrogen = (Cobalt ion (1+) • Hydrogen)

By formula: Co+ + H2 = (Co+ • H2)

Quantity Value Units Method Reference Comment
Δr82. ± 4.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(O K)=76.1 kJ/mol, ΔrS(300 K)=86.2 J/mol*K
Quantity Value Units Method Reference Comment
Δr92.0J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(O K)=76.1 kJ/mol, ΔrS(300 K)=86.2 J/mol*K

Enthalpy of reaction

ΔrH° (kJ/mol) T (K) Method Reference Comment
73.2 (+9.6,-0.) CIDHaynes and Armentrout, 1996gas phase; guided ion beam CID

(Cobalt ion (1+) • Hydrogen) + Hydrogen = (Cobalt ion (1+) • 2Hydrogen)

By formula: (Co+ • H2) + H2 = (Co+ • 2H2)

Quantity Value Units Method Reference Comment
Δr75. ± 3.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=71.1 kJ/mol, ΔrS(300 K)=103. J/mol*K
Quantity Value Units Method Reference Comment
Δr103.J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=71.1 kJ/mol, ΔrS(300 K)=103. J/mol*K

(Cobalt ion (1+) • 2Hydrogen) + Hydrogen = (Cobalt ion (1+) • 3Hydrogen)

By formula: (Co+ • 2H2) + H2 = (Co+ • 3H2)

Quantity Value Units Method Reference Comment
Δr44. ± 2.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=40. kJ/mol, ΔrS(300 K)=85.8 J/mol*K
Quantity Value Units Method Reference Comment
Δr85.8J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=40. kJ/mol, ΔrS(300 K)=85.8 J/mol*K

(Cobalt ion (1+) • 3Hydrogen) + Hydrogen = (Cobalt ion (1+) • 4Hydrogen)

By formula: (Co+ • 3H2) + H2 = (Co+ • 4H2)

Quantity Value Units Method Reference Comment
Δr44. ± 3.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=40. kJ/mol, ΔrS(300 K)=105. J/mol*K
Quantity Value Units Method Reference Comment
Δr101.J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=40. kJ/mol, ΔrS(300 K)=105. J/mol*K

(Cobalt ion (1+) • 4Hydrogen) + Hydrogen = (Cobalt ion (1+) • 5Hydrogen)

By formula: (Co+ • 4H2) + H2 = (Co+ • 5H2)

Quantity Value Units Method Reference Comment
Δr22. ± 3.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=18. kJ/mol, ΔrS(300 K)=91.6 J/mol*K
Quantity Value Units Method Reference Comment
Δr94.1J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=18. kJ/mol, ΔrS(300 K)=91.6 J/mol*K

(Cobalt ion (1+) • 5Hydrogen) + Hydrogen = (Cobalt ion (1+) • 6Hydrogen)

By formula: (Co+ • 5H2) + H2 = (Co+ • 6H2)

Quantity Value Units Method Reference Comment
Δr20. ± 3.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=17. kJ/mol, ΔrS(300 K)=99.6 J/mol*K
Quantity Value Units Method Reference Comment
Δr99.2J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=17. kJ/mol, ΔrS(300 K)=99.6 J/mol*K

(Cobalt ion (1+) • 6Hydrogen) + Hydrogen = (Cobalt ion (1+) • 7Hydrogen)

By formula: (Co+ • 6H2) + H2 = (Co+ • 7H2)

Quantity Value Units Method Reference Comment
Δr6. ± 3.kJ/molSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=3. kJ/mol; ΔrS(300 K)=75.3 J/mol*K
Quantity Value Units Method Reference Comment
Δr75.3J/mol*KSIDTKemper, Bushnell, et al., 1993, 2gas phase; ΔrH(0 K)=3. kJ/mol; ΔrS(300 K)=75.3 J/mol*K

Iron ion (1+) + Hydrogen = (Iron ion (1+) • Hydrogen)

By formula: Fe+ + H2 = (Fe+ • H2)

Quantity Value Units Method Reference Comment
Δr52.3 ± 0.8kJ/molSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 45.2 kJ/mol
Quantity Value Units Method Reference Comment
Δr90.0J/mol*KSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 45.2 kJ/mol

(Iron ion (1+) • Hydrogen) + Hydrogen = (Iron ion (1+) • 2Hydrogen)

By formula: (Fe+ • H2) + H2 = (Fe+ • 2H2)

Quantity Value Units Method Reference Comment
Δr71.1 ± 0.8kJ/molSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 65.7 kJ/mol
Quantity Value Units Method Reference Comment
Δr105.J/mol*KSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 65.7 kJ/mol

(Iron ion (1+) • 2Hydrogen) + Hydrogen = (Iron ion (1+) • 3Hydrogen)

By formula: (Fe+ • 2H2) + H2 = (Fe+ • 3H2)

Quantity Value Units Method Reference Comment
Δr35. ± 0.4kJ/molSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 31. kJ/mol
Quantity Value Units Method Reference Comment
Δr79.9J/mol*KSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 31. kJ/mol

(Iron ion (1+) • 3Hydrogen) + Hydrogen = (Iron ion (1+) • 4Hydrogen)

By formula: (Fe+ • 3H2) + H2 = (Fe+ • 4H2)

Quantity Value Units Method Reference Comment
Δr41. ± 0.4kJ/molSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 36. kJ/mol
Quantity Value Units Method Reference Comment
Δr104.J/mol*KSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 36. kJ/mol

(Iron ion (1+) • 4Hydrogen) + Hydrogen = (Iron ion (1+) • 5Hydrogen)

By formula: (Fe+ • 4H2) + H2 = (Fe+ • 5H2)

Quantity Value Units Method Reference Comment
Δr11. ± 0.4kJ/molSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 9.2 kJ/mol
Quantity Value Units Method Reference Comment
Δr74.9J/mol*KSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 9.2 kJ/mol

(Iron ion (1+) • 5Hydrogen) + Hydrogen = (Iron ion (1+) • 6Hydrogen)

By formula: (Fe+ • 5H2) + H2 = (Fe+ • 6H2)

Quantity Value Units Method Reference Comment
Δr11. ± 0.4kJ/molSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 9.6 kJ/mol
Quantity Value Units Method Reference Comment
Δr75.7J/mol*KSIDTBushnell, Kemper, et al., 1995gas phase; ΔrH(0K) = 9.6 kJ/mol

HN2+ + Hydrogen = (HN2+ • Hydrogen)

By formula: HN2+ + H2 = (HN2+ • H2)

Quantity Value Units Method Reference Comment
Δr30.kJ/molPHPMSHiraoka, Saluja, et al., 1979gas phase
Quantity Value Units Method Reference Comment
Δr94.6J/mol*KPHPMSHiraoka, Saluja, et al., 1979gas phase

(HN2+ • Hydrogen) + Hydrogen = (HN2+ • 2Hydrogen)

By formula: (HN2+ • H2) + H2 = (HN2+ • 2H2)

Quantity Value Units Method Reference Comment
Δr7.5kJ/molPHPMSHiraoka, Saluja, et al., 1979gas phase
Quantity Value Units Method Reference Comment
Δr71.J/mol*KPHPMSHiraoka, Saluja, et al., 1979gas phase

Hydroxyl anion + Hydrogen = (Hydroxyl anion • Hydrogen)

By formula: HO- + H2 = (HO- • H2)

Quantity Value Units Method Reference Comment
Δr30.kJ/molCIDPaulson and Henchman, 1984gas phase; approximate value

HO2+ + Hydrogen = (HO2+ • Hydrogen)

By formula: HO2+ + H2 = (HO2+ • H2)

Quantity Value Units Method Reference Comment
Δr52.3kJ/molPHPMSHiraoka, Saluja, et al., 1979gas phase
Quantity Value Units Method Reference Comment
Δr92.J/mol*KPHPMSHiraoka, Saluja, et al., 1979gas phase

(HO2+ • Oxygen) + Hydrogen = (HO2+ • Hydrogen • Oxygen)

By formula: (HO2+ • O2) + H2 = (HO2+ • H2 • O2)

Quantity Value Units Method Reference Comment
Δr17.kJ/molPHPMSHiraoka, Saluja, et al., 1979gas phase
Quantity Value Units Method Reference Comment
Δr71.J/mol*KPHPMSHiraoka, Saluja, et al., 1979gas phase

H3+ + Hydrogen = (H3+ • Hydrogen)

By formula: H3+ + H2 = (H3+ • H2)

Quantity Value Units Method Reference Comment
Δr29. ± 2.kJ/molAVGN/AAverage of 4 out of 11 values; Individual data points
Quantity Value Units Method Reference Comment
Δr72.8 to 72.8J/mol*KRNGN/ARange of 6 values; Individual data points

(H3+ • Hydrogen) + Hydrogen = (H3+ • 2Hydrogen)

By formula: (H3+ • H2) + H2 = (H3+ • 2H2)

Quantity Value Units Method Reference Comment
Δr14. ± 0.8kJ/molPHPMSHiraoka, 1987gas phase
Δr13.kJ/molHPMSBeuhler, Ehrenson, et al., 1983gas phase
Δr14.kJ/molHPMSBeuhler, Ehrenson, et al., 1983gas phase; deuterated
Δr17.kJ/molPHPMSHiraoka and Kebarle, 1975, 2gas phase
Δr7.5kJ/molHPMSBennett and Field, 1972gas phase; Entropy change is questionable
Quantity Value Units Method Reference Comment
Δr72.8J/mol*KPHPMSHiraoka, 1987gas phase
Δr70.7J/mol*KHPMSBeuhler, Ehrenson, et al., 1983gas phase
Δr67.4J/mol*KHPMSBeuhler, Ehrenson, et al., 1983gas phase; deuterated
Δr82.8J/mol*KPHPMSHiraoka and Kebarle, 1975, 2gas phase
Δr45.2J/mol*KHPMSBennett and Field, 1972gas phase; Entropy change is questionable

(H3+ • 2Hydrogen) + Hydrogen = (H3+ • 3Hydrogen)

By formula: (H3+ • 2H2) + H2 = (H3+ • 3H2)

Quantity Value Units Method Reference Comment
Δr13. ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Δr16.kJ/molPHPMSHiraoka and Kebarle, 1975, 2gas phase
Quantity Value Units Method Reference Comment
Δr77.4J/mol*KPHPMSHiraoka, 1987gas phase
Δr84.5J/mol*KPHPMSHiraoka and Kebarle, 1975, 2gas phase

(H3+ • 3Hydrogen) + Hydrogen = (H3+ • 4Hydrogen)

By formula: (H3+ • 3H2) + H2 = (H3+ • 4H2)

Quantity Value Units Method Reference Comment
Δr7.2 ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Δr10.kJ/molPHPMSHiraoka and Kebarle, 1975, 2gas phase
Quantity Value Units Method Reference Comment
Δr74.9J/mol*KPHPMSHiraoka, 1987gas phase
Δr80.8J/mol*KPHPMSHiraoka and Kebarle, 1975, 2gas phase

(H3+ • 4Hydrogen) + Hydrogen = (H3+ • 5Hydrogen)

By formula: (H3+ • 4H2) + H2 = (H3+ • 5H2)

Quantity Value Units Method Reference Comment
Δr6.9 ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Quantity Value Units Method Reference Comment
Δr79.1J/mol*KPHPMSHiraoka, 1987gas phase

(H3+ • 5Hydrogen) + Hydrogen = (H3+ • 6Hydrogen)

By formula: (H3+ • 5H2) + H2 = (H3+ • 6H2)

Quantity Value Units Method Reference Comment
Δr6.4 ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Quantity Value Units Method Reference Comment
Δr83.7J/mol*KPHPMSHiraoka, 1987gas phase

(H3+ • 6Hydrogen) + Hydrogen = (H3+ • 7Hydrogen)

By formula: (H3+ • 6H2) + H2 = (H3+ • 7H2)

Quantity Value Units Method Reference Comment
Δr3.7 ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Quantity Value Units Method Reference Comment
Δr69.0J/mol*KPHPMSHiraoka, 1987gas phase

(H3+ • 7Hydrogen) + Hydrogen = (H3+ • 8Hydrogen)

By formula: (H3+ • 7H2) + H2 = (H3+ • 8H2)

Quantity Value Units Method Reference Comment
Δr3.3 ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Quantity Value Units Method Reference Comment
Δr74.9J/mol*KPHPMSHiraoka, 1987gas phase

(H3+ • 8Hydrogen) + Hydrogen = (H3+ • 9Hydrogen)

By formula: (H3+ • 8H2) + H2 = (H3+ • 9H2)

Quantity Value Units Method Reference Comment
Δr2.6 ± 0.4kJ/molPHPMSHiraoka, 1987gas phase
Quantity Value Units Method Reference Comment
Δr79.9J/mol*KPHPMSHiraoka, 1987gas phase

Hydronium cation + Hydrogen = (Hydronium cation • Hydrogen)

By formula: H3O+ + H2 = (H3O+ • H2)

Quantity Value Units Method Reference Comment
Δr15. ± 2.kJ/molSCATTERINGOkumura, Yeh, et al., 1990gas phase

Potassium ion (1+) + Hydrogen = (Potassium ion (1+) • Hydrogen)

By formula: K+ + H2 = (K+ • H2)

Quantity Value Units Method Reference Comment
Δr7.78kJ/molSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 6.07 kJ/mol
Quantity Value Units Method Reference Comment
Δr56.5J/mol*KSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 6.07 kJ/mol

(Potassium ion (1+) • Hydrogen) + Hydrogen = (Potassium ion (1+) • 2Hydrogen)

By formula: (K+ • H2) + H2 = (K+ • 2H2)

Quantity Value Units Method Reference Comment
Δr6.15kJ/molSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 5.65 kJ/mol
Quantity Value Units Method Reference Comment
Δr46.9J/mol*KSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 5.65 kJ/mol

Lithium ion (1+) + Hydrogen = (Lithium ion (1+) • Hydrogen)

By formula: Li+ + H2 = (Li+ • H2)

Quantity Value Units Method Reference Comment
Δr27. ± 19.kJ/molEIWu, 1979gas phase

Sodium ion (1+) + Hydrogen = (Sodium ion (1+) • Hydrogen)

By formula: Na+ + H2 = (Na+ • H2)

Quantity Value Units Method Reference Comment
Δr12.3kJ/molSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 10.3 kJ/mol
Quantity Value Units Method Reference Comment
Δr55.2J/mol*KSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 10.3 kJ/mol

(Sodium ion (1+) • Hydrogen) + Hydrogen = (Sodium ion (1+) • 2Hydrogen)

By formula: (Na+ • H2) + H2 = (Na+ • 2H2)

Quantity Value Units Method Reference Comment
Δr10.1kJ/molSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 9.41 kJ/mol
Quantity Value Units Method Reference Comment
Δr51.9J/mol*KSIDTBushnell, Kemper, et al., 1994gas phase; ΔrH(0K) = 9.41 kJ/mol

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Ion clustering data, Notes

Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

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Wu, 1979
Wu, C.H., Binding Energies of LiH2 and LiH2+ and the Ionization Potential of LiH2, J. Chem. Phys., 1979, 71, 2, 783, https://doi.org/10.1063/1.438367 . [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Phase change data, Gas phase ion energetics data, Ion clustering data, References