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Pentaborane(9)


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.

Quantity Value Units Method Reference Comment
Deltafgas73.22kJ/molReviewChase, 1998Data last reviewed in March, 1965
Quantity Value Units Method Reference Comment
gas,1 bar275.40J/mol*KReviewChase, 1998Data last reviewed in March, 1965

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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Temperature (K) 1500. - 6000.
A 302.0563
B 16.13748
C -3.133799
D 0.210327
E -64.33193
F -166.3023
G 439.5501
H 73.22000
ReferenceChase, 1998
Comment Data last reviewed in March, 1965

Condensed 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.

Quantity Value Units Method Reference Comment
Deltafliquid42.84kJ/molReviewChase, 1998Data last reviewed in March, 1965
Quantity Value Units Method Reference Comment
liquid,1 bar183.26J/mol*KReviewChase, 1998Data last reviewed in March, 1965

Liquid 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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Temperature (K) 298. - 700.700. - 1500.
A 1777.865-50.81426
B -6068.264647.6665
C 8247.877-432.3746
D -3628.812101.0612
E -40.423469.259443
F -419.144855.06353
G 3582.106-20.65126
H 42.8441642.84416
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in March, 1965 Data last reviewed in March, 1965

Gas phase ion energetics data

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Mass spectrum (electron ionization), 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:
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 B5H9+ (ion structure unspecified)

Quantity Value Units Method Reference Comment
IE (evaluated)9.90 ± 0.03eVN/AN/AL
Quantity Value Units Method Reference Comment
Proton affinity (review)699.4kJ/molN/AHunter and Lias, 1998HL
Quantity Value Units Method Reference Comment
Gas basicity666.9kJ/molN/AHunter and Lias, 1998HL

Ionization energy determinations

IE (eV) Method Reference Comment
9.87 ± 0.02PELloyd, Lynaugh, et al., 1975LLK
9.94PEFehlner, 1975LLK
9.90PEJones and Koski, 1973LLK
10.54 ± 0.01EIMurphy and Enrione, 1970RDSH
10.5EIHollins and Stafford, 1970RDSH
10.5EIFehlner and Koski, 1964RDSH
10.38EIKaufman, Koski, et al., 1963RDSH
10.8EIMargrave, 1960RDSH
10.5PEUlman and Fehlner, 1978Vertical value; LLK

Appearance energy determinations

Ion AE (eV) Other Products MethodReferenceComment
B4H+20.0 ± 1.0?EIKaufman, Koski, et al., 1963RDSH
B4H2+18.0 ± 0.2?EIKaufman, Koski, et al., 1963RDSH
B4H3+16.0 ± 0.5?EIKaufman, Koski, et al., 1963RDSH
B4H4+14.1 ± 0.1?EIKaufman, Koski, et al., 1963RDSH
B4H5+15.1 ± 0.3?EIKaufman, Koski, et al., 1963RDSH
B4H6+12.3 ± 0.2BH3?EIKaufman, Koski, et al., 1963RDSH
B5H4+13.0 ± 0.32H2+HEIKaufman, Koski, et al., 1963RDSH
B5H5+12.5 ± 0.52H2EIHollins and Stafford, 1970RDSH
B5H5+12.8 ± 0.22H2EIFehlner and Koski, 1964RDSH
B5H5+12.67 ± 0.032H2EIKaufman, Koski, et al., 1963RDSH
B5H6+12.1 ± 0.3H2+HEIKaufman, Koski, et al., 1963RDSH
B5H7+11.4 ± 0.5H2EIHollins and Stafford, 1970RDSH
B5H7+11.6 ± 0.2H2EIFehlner and Koski, 1964RDSH
B5H7+11.4 ± 0.1H2EIKaufman, Koski, et al., 1963RDSH
B5H8+11.84 ± 0.01HEIMurphy and Enrione, 1971LLK

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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Mass spectrum
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Additional Data

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Owner NIST Mass Spectrometry Data Center
Collection (C) 2014 copyright by the U.S. Secretary of Commerce
on behalf of the United States of America. All rights reserved.
Origin API 0334
NIST MS number 190

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References

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, 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]

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]

Lloyd, Lynaugh, et al., 1975
Lloyd, D.R.; Lynaugh, N.; Roberts, P.J.; Guest, M.F., Photoelectron studies of boron and compounds, Part 5. -Higher boron hydrides B4H10, B5H9, B10H14, J. Chem. Soc. Faraday Trans. 2, 1975, 71, 1382. [all data]

Fehlner, 1975
Fehlner, T.P., Photoelectron spectroscopy of closo-carboranes. Observation of exo-polyhedral molecular orbitals, Inorg. Chem., 1975, 14, 934. [all data]

Jones and Koski, 1973
Jones, R.W.; Koski, W.S., Photoelectron spectrum of pentaborane, J. Chem. Phys., 1973, 59, 1228. [all data]

Murphy and Enrione, 1970
Murphy, C.B., Jr.; Enrione, R.E., Ionization potentials of pentaborane(9) derivatives by electron impact and molecular orbital calculations, Intern. J. Mass Spectrom. Ion Phys., 1970, 5, 157. [all data]

Hollins and Stafford, 1970
Hollins, R.E.; Stafford, F.E., Molecular beam mass spectra and pyrolysis of pentaborane(9), tetraborane carbonyl, and pentaborane(ll). Formation and mass spectrum of tetraborane(8), Inorg. Chem., 1970, 9, 877. [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]

Kaufman, Koski, et al., 1963
Kaufman, J.J.; Koski, W.S.; Kuhns, L.J.; Wright, S.S., Appearance and ionization potentials of selected fragments from isotopically labeled pentaboranes, J. Am. Chem. Soc., 1963, 85, 1369. [all data]

Margrave, 1960
Margrave, J.L., Ionization potentials of B5H9, B5H8I, B10H14, and B10H13C2H5 from electron impact studies, J. Chem. Phys., 1960, 32, 1889. [all data]

Ulman and Fehlner, 1978
Ulman, J.A.; Fehlner, T.P., Ultraviolet photoelectron spectroscopy of boranes and carboranes. Five-, six-, and seven- atom frameworks, J. Am. Chem. Soc., 1978, 100, 449. [all data]

Murphy and Enrione, 1971
Murphy, C.B., Jr.; Enrione, R.E., Bond dissociation energies of the 1- and 2- isomers of pentaborane derivatives by electron impact by extended Huckel calculations, Int. J. Mass Spectrom. Ion Phys., 1971, 7, 327. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, Mass spectrum (electron ionization), References