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Hydrogen atom

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Reaction thermochemistry data

Go To: Top, 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:
MS - José A. Martinho Simões
B - John E. Bartmess

Note: Please consider using the reaction search for this species. This page allows searching of all reactions involving this species. A general reaction search form is also available. Future versions of this site may rely on reaction search pages in place of the enumerated reaction displays seen below.

Individual Reactions

Hydromanganese pentacarbonyl (solution) = Hydrogen atom (solution) + C5MnO5 (solution)

By formula: C5HMnO5 (solution) = H (solution) + C5MnO5 (solution)

Quantity Value Units Method Reference Comment
Deltar284.5 ± 4.2kJ/molEChemParker, Handoo, et al., 1991solvent: Acetonitrile; Please also see Tilset and Parker, 1989. The reaction enthalpy was obtained from the pKa of the hydride complex (MH), 14.1, and from the oxidation potential of the anion (M-), Mn(CO)5(-), by using the equation: «DELTA»Hrxn [kJ/mol] = 5.71pKa(MH) + 96.485(Eo)ox(M-) + C. C is a constant that was calculated as 248.9 kJ/mol Parker, Handoo, et al., 1991, by adjusting the previous equation to the calorimetrically derived values for the reactions Cr(Cp)(CO)3(H)(solution) = Cr(Cp)(CO)3(solution) + H(solution), 257.3 ± 4.2 kJ/mol, and Cr(Cp)(CO)2(PPh3)(H)(solution) = Cr(Cp)(CO)2(PPh3)(solution) + H(solution), 250.2 ± 4.2 kJ/mol Kiss, Zhang, et al., 1990. C depends on the solvent and on the reference electrode. The value given implies that the electrode potentials are referenced to ferrocene/ferricinium electrode; MS
Deltar269.7kJ/molKinSBillmers, Griffith, et al., 1986solvent: Benzene; Please also see Sweany, Butler S.C., et al., 1981. The reaction enthalpy was derived according to the following procedure: the activation energy for the reaction 9,10-Me2C14H8(solution) + 2Mn(CO)5(H)(solution) = 9,10-Me2C14H10(solution) + Mn2(CO)10(solution), 90.8 kJ/mol, was reported in Sweany, Butler S.C., et al., 1981. The rate-limiting step of this reaction is the abstraction of hydrogen from Mn(CO)5(H), producing Mn(CO)5 and 9,10-Me2C14H9 radicals. Therefore, the activation energy is approximately equal to the difference between the enthalpies of the reactions Mn(CO)5(H)(solution) = Mn(CO)5(solution) + H(solution) and 9,10-Me2C14H9(solution) = 9,10-Me2C14H8(solution). The latter was taken as 178.9 kJ/mol Billmers, Griffith, et al., 1986; MS

C7H6FeO2 (solution) = C7H5FeO2 (solution) + Hydrogen atom (solution)

By formula: C7H6FeO2 (solution) = C7H5FeO2 (solution) + H (solution)

Quantity Value Units Method Reference Comment
Deltar238.9 ± 4.2kJ/molEChemParker, Handoo, et al., 1991solvent: Acetonitrile; Please also see Tilset and Parker, 1989. The reaction enthalpy was obtained from the pKa of the hydride complex (MH), 19.4, and from the oxidation potential of the anion (M-), Fe(Cp)(CO)2(-), by using the equation: «DELTA»Hrxn [kJ/mol] = 5.71pKa(MH) + 96.485(Eo)ox(M-) + C. C is a constant that was calculated as 248.9 kJ/mol Parker, Handoo, et al., 1991, by adjusting the previous equation to the calorimetrically derived values for the reactions Cr(Cp)(CO)3(H)(solution) = Cr(Cp)(CO)3(solution) + H(solution), 257.3 ± 4.2 kJ/mol, and Cr(Cp)(CO)2(PPh3)(H)(solution) = Cr(Cp)(CO)2(PPh3)(solution) + H(solution), 250.2 ± 4.2 kJ/mol Kiss, Zhang, et al., 1990. C depends on the solvent and on the reference electrode. The value given implies that the electrode potentials are referenced to ferrocene/ferricinium electrode; MS

C5HO5Re (solution) = Hydrogen atom (solution) + C5O5Re (solution)

By formula: C5HO5Re (solution) = H (solution) + C5O5Re (solution)

Quantity Value Units Method Reference Comment
Deltar312.5 ± 4.2kJ/molEChemParker, Handoo, et al., 1991solvent: Acetonitrile; Please also see Tilset and Parker, 1989. The reaction enthalpy was obtained from the pKa of the hydride complex (MH), 21.1, and from the oxidation potential of the anion (M-), Re(CO)5(-), by using the equation: «DELTA»Hrxn [kJ/mol] = 5.71pKa(MH) + 96.485(Eo)ox(M-) + C. C is a constant that was calculated as 248.9 kJ/mol Parker, Handoo, et al., 1991, by adjusting the previous equation to the calorimetrically derived values for the reactions Cr(Cp)(CO)3(H)(solution) = Cr(Cp)(CO)3(solution) + H(solution), 257.3 ± 4.2 kJ/mol, and Cr(Cp)(CO)2(PPh3)(H)(solution) = Cr(Cp)(CO)2(PPh3)(solution) + H(solution), 250.2 ± 4.2 kJ/mol Kiss, Zhang, et al., 1990. C depends on the solvent and on the reference electrode. The value given implies that the electrode potentials are referenced to ferrocene/ferricinium electrode; MS

Cobalt, tetracarbonylhydro- (solution) = Hydrogen atom (solution) + Cobalt, tetracarbonyl (solution)

By formula: C4HCoO4 (solution) = H (solution) + C4CoO4 (solution)

Quantity Value Units Method Reference Comment
Deltar277.8 ± 4.2kJ/molEChemParker, Handoo, et al., 1991solvent: Acetonitrile; Please also see Tilset and Parker, 1989. The reaction enthalpy was obtained from the pKa of the hydride complex (MH), 8.3, and from the oxidation potential of the anion (M-), Co(CO)4(-), by using the equation: «DELTA»Hrxn [kJ/mol] = 5.71pKa(MH) + 96.485(Eo)ox(M-) + C. C is a constant that was calculated as 248.9 kJ/mol Parker, Handoo, et al., 1991, by adjusting the previous equation to the calorimetrically derived values for the reactions Cr(Cp)(CO)3(H)(solution) = Cr(Cp)(CO)3(solution) + H(solution), 257.3 ± 4.2 kJ/mol, and Cr(Cp)(CO)2(PPh3)(H)(solution) = Cr(Cp)(CO)2(PPh3)(solution) + H(solution), 250.2 ± 4.2 kJ/mol Kiss, Zhang, et al., 1990. C depends on the solvent and on the reference electrode. The value given implies that the electrode potentials are referenced to ferrocene/ferricinium electrode; MS

C4H2FeO4 (g) = 2Hydrogen atom (g) + C4FeO4 (g)

By formula: C4H2FeO4 (g) = 2H (g) + C4FeO4 (g)

Quantity Value Units Method Reference Comment
Deltar545.kJ/molESTMiller and Beauchamp, 1991Please also see Martinho Simões and Beauchamp, 1990. The reaction enthalpy was estimated from the activation enthalpy for thermal decomposition in solution, 109. ± 8. kJ/mol Pearson and Mauermann, 1982, yielding Fe(CO)4 and H2, and from the activation enthalpy of the oxidative addition of H2 to Fe(CO)4 in a rare gas matrix, ca. 0. kJ/mol Sweany, 1981, yielding Fe(CO)4H2. The enthalpy of formation relies on -440. ± 14. kJ/mol for the enthalpy of formation of Fe(CO)4(g); MS

Hydromanganese pentacarbonyl (g) = Hydrogen atom (g) + C5MnO5 (g)

By formula: C5HMnO5 (g) = H (g) + C5MnO5 (g)

Quantity Value Units Method Reference Comment
Deltar245. ± 17.kJ/molPIMSMartinho Simões and Beauchamp, 1990The reaction enthalpy was derived from the appearance energy of Mn(CO)5(+), 993.8 ± 9.6 kJ/mol, using Mn(CO)5(H) as the neutral precursor, together with the adiabatic ionization energy of Mn(CO)5 radical, 749. ± 14. kJ/mol Martinho Simões and Beauchamp, 1990; MS

C3H10Ge (g) = C3H9Ge (g) + Hydrogen atom (g)

By formula: C3H10Ge (g) = C3H9Ge (g) + H (g)

Quantity Value Units Method Reference Comment
Deltar334. ± 12.kJ/molICRBrinkman, Salomon, et al., 1995The reaction enthalpy was derived from the acidity of Ge(Me)3(H)(g), 1513. ± 12. kJ/mol, the electron affinity of Ge(Me)3(g), 133.5 ± 2.9 kJ/mol Brinkman, Salomon, et al., 1995, and the ionization energy of H(g), 1312.0 kJ/mol Lias, Bartmess, et al., 1988.; MS

C3H10Sn (g) = Hydrogen atom (g) + Trimethyltin (g)

By formula: C3H10Sn (g) = H (g) + C3H9Sn (g)

Quantity Value Units Method Reference Comment
Deltar312. ± 11.kJ/molICRBrinkman, Salomon, et al., 1995The reaction enthalpy was derived from the acidity of Sn(Me)3(H)(g), 1460.2 ± 8.4 kJ/mol, the electron affinity of Sn(Me)3(g), 164.0 ± 6.3 kJ/mol Brinkman, Salomon, et al., 1995, and the ionization energy of H(g), 1312.0 kJ/mol Lias, Bartmess, et al., 1988.; MS

Germane (g) = Hydrogen atom (g) + Germyl radical (g)

By formula: H4Ge (g) = H (g) + H3Ge (g)

Quantity Value Units Method Reference Comment
Deltar348.9 ± 8.4kJ/molPIMSBerkowitz, Ellison, et al., 1994Please also see Ruscic, Schwarz, et al., 1990. Value recommended in the critical survey Berkowitz, Ellison, et al., 1994.; MS
Deltar<358.kJ/molPIMSRuscic, Schwarz, et al., 1990Temperature: 0 K. A value of 343. ± 8. kJ/mol is recommended in Ruscic, Schwarz, et al., 1990.; MS

e- + Hydrogen cation = Hydrogen atom

By formula: e- + H+ = H

Quantity Value Units Method Reference Comment
Deltar1318.4kJ/molAcidWagman, Evans, et al., 1982gas phase; Using the "electron convention". Acid = H.; B
Quantity Value Units Method Reference Comment
Deltar1313.8kJ/molH-TSWagman, Evans, et al., 1982gas phase; Using the "electron convention". Acid = H.; B

Germyl radical (g) = Hydrogen atom (g) + Germylene (g)

By formula: H3Ge (g) = H (g) + H2Ge (g)

Quantity Value Units Method Reference Comment
Deltar>236.kJ/molPIMSRuscic, Schwarz, et al., 1990Temperature: 0 K. A value of 247. kJ/mol is recommended in Ruscic, Schwarz, et al., 1990.; MS

Germylene (g) = HGe (g) + Hydrogen atom (g)

By formula: H2Ge (g) = HGe (g) + H (g)

Quantity Value Units Method Reference Comment
Deltar<288.kJ/molPIMSRuscic, Schwarz, et al., 1990Temperature: 0 K. A value of 277. kJ/mol is recommended in Ruscic, Schwarz, et al., 1990.; MS

HGe (g) = Hydrogen atom (g) + germanium (g)

By formula: HGe (g) = H (g) + Ge (g)

Quantity Value Units Method Reference Comment
Deltar>225.kJ/molPIMSRuscic, Schwarz, et al., 1990Temperature: 0 K. A value of 264. kJ/mol is recommended in Ruscic, Schwarz, et al., 1990.; MS

H3Sb (g) = Hydrogen atom (g) + H2Sb (g)

By formula: H3Sb (g) = H (g) + H2Sb (g)

Quantity Value Units Method Reference Comment
Deltar288.3 ± 2.1kJ/molPIMSBerkowitz, Ellison, et al., 1994Value recommended in the critical survey Berkowitz, Ellison, et al., 1994.; MS

C13H26IrP (solution) = C13H24IrP (solution) + 2Hydrogen atom (g)

By formula: C13H26IrP (solution) = C13H24IrP (solution) + 2H (g)

Quantity Value Units Method Reference Comment
Deltar620.kJ/molESTNolan, Hoff, et al., 1987Please also see Stoutland, Bergman, et al., 1988.; MS

(CAS Reg. No. 952499-85-3 bullet 4294967295Hydrogen atom) + Hydrogen atom = CAS Reg. No. 952499-85-3

By formula: (CAS Reg. No. 952499-85-3 bullet 4294967295H) + H = CAS Reg. No. 952499-85-3

Quantity Value Units Method Reference Comment
Deltar187. ± 18.kJ/molN/ACalvi, Andrews, et al., 2007gas phase; B

C13H26IrP (solution) = C13H25IrP (solution) + Hydrogen atom (g)

By formula: C13H26IrP (solution) = C13H25IrP (solution) + H (g)

Quantity Value Units Method Reference Comment
Deltar305. ± 18.kJ/molPACNolan, Hoff, et al., 1987MS

References

Go To: Top, Reaction thermochemistry data, Notes

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

Parker, Handoo, et al., 1991
Parker, V.D.; Handoo, K.L.; Roness, F.; Tilset, M., J. Am. Chem. Soc., 1991, 113, 7493. [all data]

Tilset and Parker, 1989
Tilset, M.; Parker, V.D., J. Am. Chem. Soc., 1989, 111, 6711; ibid. 1990. [all data]

Kiss, Zhang, et al., 1990
Kiss, G.; Zhang, K.; Mukerjee, S.L.; Hoff, C.; Roper, G.C., J. Am. Chem. Soc., 1990, 112, 5657. [all data]

Billmers, Griffith, et al., 1986
Billmers, R.; Griffith, L.L.; Stein, S.E., J. Phys. Chem., 1986, 90, 517. [all data]

Sweany, Butler S.C., et al., 1981
Sweany, R.; Butler S.C.; Halpern, J., J. Organometal. Chem., 1981, 213, 487. [all data]

Miller and Beauchamp, 1991
Miller, A.E.S.; Beauchamp, J.L., J. Am. Chem. Soc., 1991, 113, 8765. [all data]

Martinho Simões and Beauchamp, 1990
Martinho Simões, J.A.; Beauchamp, J.L., Chem. Rev., 1990, 90, 629. [all data]

Pearson and Mauermann, 1982
Pearson, R.G.; Mauermann, H., J. Am. Chem. Soc., 1982, 104, 500. [all data]

Sweany, 1981
Sweany, R.L., J. Am. Chem. Soc., 1981, 103, 2410. [all data]

Brinkman, Salomon, et al., 1995
Brinkman, E.A.; Salomon, K.; Tumas, W.; Brauman, J.I., Electron affinities and gas-phase acidities of organogermanium and organotin compounds, J. Am. Chem. Soc., 1995, 117, 17, 4905, https://doi.org/10.1021/ja00122a022 . [all data]

Lias, Bartmess, et al., 1988
Lias, S.G.; Bartmess, J.E.; Liebman, J.F.; Holmes, J.L.; Levin, R.D.; Mallard, W.G., Gas-Phase Ion and Neutral Thermochemistry, J. Phys. Chem. Ref. Data, 1988, 17, Suppl. 1. [all data]

Berkowitz, Ellison, et al., 1994
Berkowitz, J.; Ellison, G.B.; Gutman, D., Three methods to measure RH bond energies, J. Phys. Chem., 1994, 98, 2744. [all data]

Ruscic, Schwarz, et al., 1990
Ruscic, B.; Schwarz, M.; Berkowitz, J., Photoionization studies of GeHn(n = 2-4), J. Chem. Phys., 1990, 92, 1865. [all data]

Wagman, Evans, et al., 1982
Wagman, D.D.; Evans, W.H.; Parker, V.B.; Schumm, R.H.; Halow, I.; Bailey, S.M.; Churney, K.L.; Nuttall, R.L., The NBS Tables of Chemical Thermodynamic Properties (NBS Tech Note 270), J. Phys. Chem. Ref. Data, Supl. 1, 1982, 11. [all data]

Nolan, Hoff, et al., 1987
Nolan, S.P.; Hoff, C.D.; Stoutland, P.O.; Newman, L.J.; Buchanan, J.M.; Bergman, R.G.; Yang, G.K.; Peters, K.S., J. Am. Chem. Soc., 1987, 109, 3143. [all data]

Stoutland, Bergman, et al., 1988
Stoutland, P.O.; Bergman, R.G.; Nolan, S.P.; Hoff, C.D., Polyhedron, 1988, 7, 1429. [all data]

Calvi, Andrews, et al., 2007
Calvi, R.M.D.; Andrews, D.H.; Lineberger, W.C., Negative ion photoelectron spectroscopy of copper hydrides, Chem. Phys. Lett., 2007, 442, 1-3, 12-16, https://doi.org/10.1016/j.cplett.2007.05.060 . [all data]


Notes

Go To: Top, Reaction thermochemistry data, References