Diborane

• Formula: B₂H₆
• Molecular weight: 27.670
• IUPAC Standard InChI: InChI=1S/B2H2/c1-3-2-4-1 Copy

  
• IUPAC Standard InChIKey: GCXMMZWJUYHRTG-UHFFFAOYSA-N Copy
• CAS Registry Number: 19287-45-7
• Chemical structure:
  This structure is also available as a 2d Mol file
• Other names: Diborane(6); Boron hydride (B2H6); Diboron hexahydride; Boroethane; Boron hydride; UN 1911; B2H6
• Permanent link for this species. Use this link for bookmarking this species for future reference.
• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Gas phase ion energetics data
  • References
  • Notes
• Other data available:
  • Reaction thermochemistry data
  • Ion clustering data
  • IR Spectrum
  • Mass spectrum (electron ionization)
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
• Options:
  • Switch to calorie-based units

Data at NIST subscription sites:

• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

NIST subscription sites provide data under the NIST Standard Reference Data Program, but require an annual fee to access. The purpose of the fee is to recover costs associated with the development of data collections included in such sites. Your institution may already be a subscriber. Follow the links above to find out more about the data in these sites and their terms of usage.

Gas phase thermochemistry data

Go To: Top, 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.

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.

View plot Requires a JavaScript / HTML 5 canvas capable browser.

View table.

Phase change data

Go To: Top, Gas phase thermochemistry 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 as indicated in comments:
AC - William E. Acree, Jr., James S. Chickos

Enthalpy of vaporization

Antoine Equation Parameters

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

View plot Requires a JavaScript / HTML 5 canvas capable browser.

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Phase change 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:
LL - Sharon G. Lias and Joel F. Liebman
LLK - Sharon G. Lias, Rhoda D. Levin, and Sherif A. Kafafi
RDSH - Henry M. Rosenstock, Keith Draxl, Bruce W. Steiner, and John T. Herron

Ionization energy determinations

Appearance energy determinations

References

Go To: Top, Gas phase thermochemistry data, Phase change 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]

Ditter, Perrine, et al., 1961
Ditter, J.F.; Perrine, J.C.; Shapiro, Isadore, Vapor Pressure of Deuterodiborane., J. Chem. Eng. Data, 1961, 6, 2, 271-271, https://doi.org/10.1021/je60010a026 . [all data]

Paridon, MacWood, et al., 1959
Paridon, Leo J.; MacWood, George E.; Hu, Jih-Heng, The Heat of Vaporization of Diborane, J. Phys. Chem., 1959, 63, 12, 1998-1999, https://doi.org/10.1021/j150582a004 . [all data]

Ditter, Perrine, et al., 1961, 2
Ditter, J.F.; Perrine, J.C.; Shapiro, I., Vapor Pressure of Deuterodiborane, J. Chem. Eng. Data, 1961, 6, 2, 271, https://doi.org/10.1021/je60010a026 . [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]

Ruscic, Mayhew, et al., 1988
Ruscic, B.; Mayhew, C.A.; Berkowitz, J., Photoionization studies of (BH₃)_n(n=1,2), J. Chem. Phys., 1988, 88, 5580. [all data]

Asbrink, Svensson, et al., 1981
Asbrink, L.; Svensson, A.; Von Niessen, W.; Bieri, G., 30.4 nm He(II) photoelectron spectra of organic molecules, J. Electron Spectrosc. Relat. Phenom., 1981, 24, 293. [all data]

Lloyd and Lynaugh, 1970
Lloyd, D.R.; Lynaugh, N., Photoelectron studies of boron compounds. I. Diborane, borazine and B-trifluoroborazine, Phil. Trans. Roy. Soc. (London), 1970, A268, 97. [all data]

Brundle, Robin, et al., 1970
Brundle, C.R.; Robin, M.B.; Basch, H.; Pinsky, M.; Bond, A., Experimental and theoretical comparison of the electronic structures of ethylene and diborane, J. Am. Chem. Soc., 1970, 92, 3863. [all data]

Rose, Frey, et al., ibid.
Rose, T.; Frey, R.; Brehm, B., The electronic states of the diborane ion determined by photoelectron spectroscopy, Chem. Commun. 1969,,1518; Erratum,, ibid., 1970, ,460. [all data]

Wilson and McGee, 1967
Wilson, J.H.; McGee, H.A., Jr., Mass-spectrometric studies of the synthesis, energetics, and cryogenic stability of the lower boron hydrides, J. Chem. Phys., 1967, 46, 1444. [all data]

Koski, Kaufman, et al., 1958
Koski, W.S.; Kaufman, J.J.; Pachucki, C.F.; Shipko, F.J., A mass spectrometric appearance potential study of isotopically labeled diboranes, J. Am. Chem. Soc., 1958, 80, 3202. [all data]

Margrave, 1957
Margrave, J.L., A mass spectrometric appearance potential study of diborane, J. Phys. Chem., 1957, 61, 38. [all data]

Fehlner and Koski, 1964
Fehlner, T.P.; Koski, W.S., The fragmentation of some boron hydrides by electron impact, J. Am. Chem. Soc., 1964, 86, 581. [all data]

Notes

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

• Symbols used in this document:
  

  AE	Appearance energy
  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
  ΔvapH	Enthalpy of vaporization

• Data from NIST Standard Reference Database 69: NIST Chemistry WebBook
• The National Institute of Standards and Technology (NIST) uses its best efforts to deliver a high quality copy of the Database and to verify that the data contained therein have been selected on the basis of sound scientific judgment. However, NIST makes no warranties to that effect, and NIST shall not be liable for any damage that may result from errors or omissions in the Database.
• Customer support for NIST Standard Reference Data products.