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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.

Quantity Value Units Method Reference Comment
Deltafgas618.40kJ/molReviewChase, 1998Data last reviewed in March, 1979
Quantity Value Units Method Reference Comment
gas,1 bar186.90J/mol*KReviewChase, 1998Data last reviewed in March, 1979

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) 4963.793 - 6000.
A 53.43135
B -14.43208
C 3.215568
D -0.181469
E -20.49164
F 567.3881
G 217.1521
H 618.3952
ReferenceChase, 1998
Comment Data last reviewed in March, 1979

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
Deltafliquid46.21kJ/molReviewChase, 1998Data last reviewed in March, 1979
Quantity Value Units Method Reference Comment
liquid,1 bar71.94J/mol*KReviewChase, 1998Data last reviewed in March, 1979

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) 2500. - 4963.793
A 37.65604
B -1.195850×10-7
C 2.633457×10-8
D -1.977226×10-9
E -1.780309×10-7
F 15.45084
G 90.56477
H 46.20893
ReferenceChase, 1998
Comment Data last reviewed in March, 1979

Solid 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. - 2500.298. - 2500.
A 22.7103314.99366
B 10.864439.234131
C -1.901809-0.000539
D 0.3063680.000106
E -0.0075870.000024
F -7.26430313.82318
G 67.8435676.50360
H 0.00000018.68604
ReferenceChase, 1998Chase, 1998
Comment «alpha» phase; Data last reviewed in March, 1979 «beta» phase; Data last reviewed in March, 1979

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:
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

Quantity Value Units Method Reference Comment
IE (evaluated)6.82507 ± 0.00004eVN/AN/AL

Ionization energy determinations

IE (eV) Method Reference Comment
6.82507EVALLide, 1992LL
6.82507 ± 0.00004LSCallender, Hackett, et al., 1988LL
6.65 ± 0.10EIRauh and Ackermann, 1979LLK
6.7 ± 0.1EIRauh and Ackermann, 1974LLK

References

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

Lide, 1992
Lide, D.R. (Editor), Ionization potentials of atoms and atomic ions in Handbook of Chem. and Phys., 1992, 10-211. [all data]

Callender, Hackett, et al., 1988
Callender, C.L.; Hackett, P.A.; Rayner, D.M., First ionization potential of hafnium by double-resonance field-ionization spectroscopy, J. Opt. Soc. Am. B, 1988, 5, 1341. [all data]

Rauh and Ackermann, 1979
Rauh, E.G.; Ackermann, R.J., The first ionization potentials of the transition metals, J. Chem. Phys., 1979, 70, 1004. [all data]

Rauh and Ackermann, 1974
Rauh, E.G.; Ackermann, R.J., First ionization potentials of some refractory oxide vapors, J. Chem. Phys., 1974, 60, 1396. [all data]


Notes

Go To: Top, Gas phase thermochemistry data, Condensed phase thermochemistry data, Gas phase ion energetics data, NIST Free Links, References