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
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• Information on this page:
  • Gas phase thermochemistry data
  • Phase change data
  • Reaction thermochemistry data
  • Gas phase ion energetics data
  • IR Spectrum
  • Mass spectrum (electron ionization)
  • References
  • Notes
• Other data available:
  • Ion clustering data
• Data at other public NIST sites:
  • Gas Phase Kinetics Database
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• NIST / TRC Web Thermo Tables, professional edition (thermophysical and thermochemical data)

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

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Phase change 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 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 (atm)
    T = temperature (K)

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Reaction 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.

Data compiled by: 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

 +  = ( • )

By formula: H^- + H₆B₂ = (H^- • H₆B₂)

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
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

IR Spectrum

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Data compiled by: Coblentz Society, Inc.

• Not specified, most likely a prism, grating, or hybrid spectrometer.; (NO SPECTRUM, ONLY SCANNED IMAGE IS AVAILABLE)
• GAS AT 50 mmHg PRESSURE; $$ PURITY 98+%; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution
• SOLUTION (2.54 mg/ml IN 2,3-DIMETHYLBUTANE); $$ 95+% PURITY; Not specified, most likely a prism, grating, or hybrid spectrometer.; DIGITIZED BY NIST FROM HARD COPY; 4 cm^-1 resolution

Mass spectrum (electron ionization)

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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 compiled by: NIST Mass Spectrometry Data Center, William E. Wallace, director

Spectrum

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Additional Data

References

Go To: Top, Gas phase thermochemistry data, Phase change data, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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]

Workman and Squires, 1988
Workman, D.B.; Squires, R.R., Hydride Binding Energies of Boranes, Inorg. Chem., 1988, 27, 11, 1846, https://doi.org/10.1021/ic00284a003 . [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, Reaction thermochemistry data, Gas phase ion energetics data, IR Spectrum, Mass spectrum (electron ionization), 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
  ΔrH°	Enthalpy of reaction at standard conditions
  ΔvapH	Enthalpy of vaporization

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