Beryllium monofluoride


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
Δfgas-40.600kcal/molReviewChase, 1998Data last reviewed in December, 1971
Quantity Value Units Method Reference Comment
gas,1 bar49.175cal/mol*KReviewChase, 1998Data last reviewed in December, 1971

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

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Temperature (K) 298. - 1100.1100. - 6000.
A 4.6296208.743010
B 8.9605690.227576
C -7.204711-0.041374
D 2.1301800.004116
E 0.037527-0.381616
F -42.19319-44.21530
G 52.6193158.26991
H -40.59990-40.59990
ReferenceChase, 1998Chase, 1998
Comment Data last reviewed in December, 1971 Data last reviewed in December, 1971

Constants of diatomic molecules

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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: Klaus P. Huber and Gerhard H. Herzberg

Data collected through April, 1976

Symbols used in the table of constants
SymbolMeaning
State electronic state and / or symmetry symbol
Te minimum electronic energy (cm-1)
ωe vibrational constant – first term (cm-1)
ωexe vibrational constant – second term (cm-1)
ωeye vibrational constant – third term (cm-1)
Be rotational constant in equilibrium position (cm-1)
αe rotational constant – first term (cm-1)
γe rotation-vibration interaction constant (cm-1)
De centrifugal distortion constant (cm-1)
βe rotational constant – first term, centrifugal force (cm-1)
re internuclear distance (Å)
Trans. observed transition(s) corresponding to electronic state
ν00 position of 0-0 band (units noted in table)
Diatomic constants for 9Be19F
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
R shaded double-headed emission bands in the region 62900 - 64100 and 65800 - 66700 cm-1.
Novikov and Gurvich, 1967
C 2Σ+ 50364.0 1419.7 H 9.9  1.570 0.014    1.325 C → A V 17253.7
Rao and Rao, 1965
           C → X V 50440.86 Z
missing citation
B 2Σ+ 49563.9 1350.8 H 12.6  [1.547]     [1.335] B → X V 49605.6 Z
missing citation
StateTeωeωexeωeyeBeαeγeDeβereTrans.ν00
A 2Πr 33233.7 1 [1154.67] Z 8.78 2 HQ  1.42024 3 0.0175  [8.40E-06] 4  1.3935 A ↔ X R 33187.13 5 Z
missing citation; missing citation; Mulliken, 1931; Fowler, 1941; Tatevskii, Tunitskii, et al., 1958; Walker and Barrow, 1969
X 2Σ+ 0 [1247.36] Z 9.12 2 HQ  1.48893 0.0176  0.00000828  1.3610  

Notes

1A0=+21.82, A1=+21.93; slight J dependence. A negative value of A has been ruled out by the calculations of Walker and Richards, 1970.
2Slightly different constants in Tatevskii, Tunitskii, et al., 1958.
3The Λ-type doubling in the 1/2 and 3/2 components Walker and Barrow, 1969 does not follow the "pure precession" pattern for a regular 2Π state. An earlier explanation Walker and Richards, 1967 of this "anomaly" has since been revised Walker and Richards, 1970.
4D1 = 8.26E-6.
5J'=1/2 (average of F1 and {F2}) relative to N"=0.
6Mass-spectrometric values Hildenbrand and Murad, 1966, Farber and Srivastava, 1974.

References

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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]

Novikov and Gurvich, 1967
Novikov, M.M.; Gurvich, L.V., The emission spectrum of BeF in the vacuum ultraviolet, Opt. Spectrosc. Engl. Transl., 1967, 23, 173, In original 323. [all data]

Rao and Rao, 1965
Rao, K.M.; Rao, P.T., A new electronic transition in the BeF molecule, Indian J. Pure Appl. Phys., 1965, 3, 177. [all data]

Mulliken, 1931
Mulliken, R.S., Note on the interpretation of the BeF bands, Phys. Rev., 1931, 00, 836. [all data]

Fowler, 1941
Fowler, C.A., Jr., New absorption spectra of the alkaline earth fluorides, Phys. Rev., 1941, 59, 645. [all data]

Tatevskii, Tunitskii, et al., 1958
Tatevskii, V.M.; Tunitskii, L.N.; Novikov, M.M., Vibration constant and dissociation energy of the BeF molecule, Opt. Spektrosk., 1958, 5, 520. [all data]

Walker and Barrow, 1969
Walker, T.E.H.; Barrow, R.F., The A2Π-X2Σ+ system of BeF, J. Phys. B:, 1969, 2, 102. [all data]

Walker and Richards, 1970
Walker, T.E.H.; Richards, W.G., The assignment of molecular orbital configurations on the basis of λ-type doubling, J. Phys., 1970, 3, 271. [all data]

Walker and Richards, 1967
Walker, T.E.H.; Richards, W.G., The nature of the first excited electronic state in BeF, Proc. Phys. Soc. London, 1967, 92, 285. [all data]

Hildenbrand and Murad, 1966
Hildenbrand, D.L.; Murad, E., Mass-spectrometric determination of the dissociation energy of beryllium monofluoride, J. Chem. Phys., 1966, 44, 1524. [all data]

Farber and Srivastava, 1974
Farber, M.; Srivastava, R.D., Dissociation energies of BeF and BeCl and the heat of formation of BeClF, J. Chem. Soc. Faraday Trans. 1, 1974, 70, 1581. [all data]


Notes

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