Disodium

• Formula: Na₂
• Molecular weight: 45.97953856
• IUPAC Standard InChI: InChI=1S/2Na Copy

  
• IUPAC Standard InChIKey: QXNVGIXVLWOKEQ-UHFFFAOYSA-N Copy
• CAS Registry Number: 25681-79-2
• Chemical structure:
  This structure is also available as a 2d Mol file or as a computed 3d SD file
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• Information on this page:
  • Gas phase thermochemistry data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Ion clustering data
  • Constants of diatomic molecules
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Gas phase thermochemistry data

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

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

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Gas phase ion energetics data

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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:
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
B - John E. Bartmess

Electron affinity determinations

Ionization energy determinations

Appearance energy determinations

References

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

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

Chase, 1998
Chase, M.W., Jr., NIST-JANAF Themochemical Tables, Fourth Edition, J. Phys. Chem. Ref. Data, Monograph 9, 1998, 1-1951. [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]

McHugh, Eaton, et al., 1989
McHugh, K.M.; Eaton, J.G.; Lee, G.H.; Sarkas, H.W.; Kidder, L.H.; Snodgrass, J.T.; Manaa, M.R.; Bowen, K.H., Photoelectron Spectra of the alkali metal cluster Anions: Na-,n=2-5, K-,n=2-7, Rb-,n=2-3, and Cs-,n=2-3, J. Chem. Phys., 1989, 91, 6, 3792, https://doi.org/10.1063/1.456861 . [all data]

Buhler, 1990
Buhler, B., [Title unavailable], Ph. D. Thesis, Fakultat fur Physik, Universitat Freiburg, 1990. [all data]

Kappes, Radi, et al., 1985
Kappes, M.M.; Radi, P.; Schar, M.; Schumacher, E., Photoionization measurements on dialkali monohalides generated in supersonic nozzle beams, Chem. Phys. Lett., 1985, 113, 243. [all data]

Peterson, Dao, et al., 1984
Peterson, K.I.; Dao, P.D.; Farley, R.W.; Castleman, A.W., Jr., Photoionization of sodium clusters, J. Chem. Phys., 1984, 80, 1780. [all data]

Martin, Chevaleyre, et al., 1982
Martin, S.; Chevaleyre, J.; Valignat, S.; Perrot, J.P.; Broyer, M.; Cabaud, B.; Hoareau, A., Autoionizing Rydberg states of the Na₂ molecule, Chem. Phys. Lett., 1982, 87, 235. [all data]

Leutwyler, Hofmann, et al., 1981
Leutwyler, S.; Hofmann, M.; Harri, H.-P.; Schumacher, E., The adiabatic ionization potentials of the alkali dimers Na₂, NaK and K₂, Chem. Phys. Lett., 1981, 77, 257. [all data]

Herrmann, Schumacher, et al., 1978
Herrmann, A.; Schumacher, E.; Woste, L., Preparation and photoionization potentials of molecules of sodium, potassium and mixed atoms, J. Chem. Phys., 1978, 68, 2327. [all data]

Herrmann, Leutwyler, et al., 1978
Herrmann, A.; Leutwyler, S.; Schumacher, E.; Woste, L., 38. On metal-atom clusters IV. Photoionization thresholds and multiphoton ionization spectra of alkali-metal molecules, Helv. Chim. Acta, 1978, 61, 453. [all data]

Zmbov, Wu, et al., 1977
Zmbov, K.F.; Wu, C.H.; Ihle, H.R., A mass spectrometric study of heteronuclear diatomic alkali metal molecules. Dissociation energies ionization potentials of NaLi, KLi, NaK, J. Chem. Phys., 1977, 67, 4603. [all data]

Emel'yanov, Peredvigina, et al., 1971
Emel'yanov, A.M.; Peredvigina, V.A.; Gorokhov, L.N., Ionization potentials of Li₂ and Na₂ molecules and the dissociation energy of Li₂⁺ and Na₂⁺ ions, Teplofiz. Vysokikh Temperatur, 1971, 9, 190, In original 164. [all data]

Robbins, Leckenby, et al., 1967
Robbins, E.J.; Leckenby, R.E.; Willis, P., The ionization potentials of clustered sodium atoms, Advan. Phys., 1967, 16, 739. [all data]

Hudson, 1965
Hudson, R.D., Measurements of the molecular absorption cross section and the photoionization of sodium vapor between 1600 and 3700, J. Chem. Phys., 1965, 43, 1790. [all data]

Barrow, Travis, et al., 1960
Barrow, R.F.; Travis, N.; Wright, C.V., Excited electronic states of lithium and sodium molecules, Nature, 1960, 187, 141. [all data]

Wagner and Isenor, 1983
Wagner, G.; Isenor, N.R., Formation and dissociation of Na₂⁺ by ruby laser radiation, Can. J. Phys., 1983, 61, 40. [all data]

Notes

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• Symbols used in this document:
  

  AE	Appearance energy
  EA	Electron affinity
  IE (evaluated)	Recommended ionization energy
  S°gas,1 bar	Entropy of gas at standard conditions (1 bar)
  ΔfH°gas	Enthalpy of formation of gas at standard conditions

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