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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 January, 1977

Symbols used in the table of constants
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 H19F+
           c 678.2 $eV
Shaw and Thomas, 1975
           c 23.6 $eV
Shaw and Thomas, 1975
A 2Sigma+ 25449.82 1 1496.07 Z 88.423 -7.328 11.7536 2 3 1.0261 4 -0.0933 [28.89E-4] 5  1.2242 A rarrow X R 24648.91 6
Gewurtz, Lew, et al., 1975
X 2Pii 0 7 3090.48 Z 88.996 8  17.5771 9 10 8.8863 11 0.0142 [22.05E-4] 12  1.0011  


1Includes the Y00 corrections in the upper and lower states; Y"00 - Y'00 = 2.93 cm-1.
2Spin splitting constants gamma(v=0) = 0.5339, gamma(v=1)= 0.5400, gamma(v=2)= 0.5665, gamma(v=3)= 0.644.
3Breaking off of rotational levels at N=3 for v=3 and N=10 for v=2 because of predissociation by rotation. The predissociation limit is 27966 ± 50 cm-1 above J=3/2, v=0 of 2Pi3/2 and corresponds to dissociation into H+ + F(2P1/2); see, however, the discussion in Gewurtz, Lew, et al., 1975.
4From v=0,1,2 only. B3 = 6.741.
5D1 = 31.65E-4, D2 = 39.3E-4; H0 = -3.2E-7, H1 = -11.3E-7, H2 = -34E-7.
6Refers to the zero-point of the Hill-Van Vleck formula in the lower state.
7A(v) = -292.85 + 0.58(v+1/2); see 8.
8Only v=0,1,2 have been observed with high accuracy in the optical spectrum, v=3...11 in the photoelectron spectrum Guyon, Spohr, et al., 1976.
9For Lambda-type doubling constants (p ~ 0.60) see Gewurtz, Lew, et al., 1975.
10Ab initio calculations Julienne, Krauss, et al., 1971, Bondybey, Pearson, et al., 1972, Raftery and Richards, 1972 give molecular constants in agreement with the experimental results quoted here.
11See 8.
12D1 = 21.41E-4; D2 = 21.24E-4.
13Average of two values, 27650 and 27562 cm-1, the former from D00(HF) + I.P.(H) - I.P.(HF), the latter from the predissociation in A 2Sigma+ (see 3).
14Several excited states of HF++ were observed in the Auger electron spectrum of HF Shaw and Thomas, 1975. Tentatively, the ...sigma2pi2 1Delta and 1Sigma states may be identified at 33.9 and 35.9 eV above X 2Pi3/2(v=0) of HF+; the 3Sigma state remains undetected.
15From X-ray photoelectron spectra; satellite ("shake-up") peaks corresponding to 25- 35 eV higher excitation energies than the main 1sigma peak were observed by Martin, Mills, et al., 1976 and attributed to simultaneous removal of an F 1s electron and excitation of a 3sigma or 1pi electron into a higher orbital.


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Data compilation copyright by the U.S. Secretary of Commerce on behalf of the U.S.A. All rights reserved.

Shaw and Thomas, 1975
Shaw, R.W., Jr.; Thomas, T.D., Auger electron spectrum and ionization potentials of the HF molecule, Phys. Rev. A:, 1975, 11, 1491. [all data]

Gewurtz, Lew, et al., 1975
Gewurtz, S.; Lew, H.; Flainek, P., The electronic spectrum of HF+, Can. J. Phys., 1975, 53, 1097. [all data]

Guyon, Spohr, et al., 1976
Guyon, P.-M.; Spohr, R.; Chupka, W.A.; Berkowitz, J., Threshold photoelectron spectra of HF, DF, and F2, J. Chem. Phys., 1976, 65, 1650-1658. [all data]

Julienne, Krauss, et al., 1971
Julienne, P.S.; Krauss, M.; Wahl, A.C., Hartree-Fock energy curves for X2«PI» and 2«SIGMA»+ states of HF+, Chem. Phys. Lett., 1971, 11, 16. [all data]

Bondybey, Pearson, et al., 1972
Bondybey, V.; Pearson, P.K.; Schaefer, H.F., III, Theoretical potential energy curves for OH, HF+, HF, HF-, NeH+, and NeH, J. Chem. Phys., 1972, 57, 1123. [all data]

Raftery and Richards, 1972
Raftery, J.; Richards, W.G., The electronic structure of HF+, J. Phys. B:, 1972, 5, 425. [all data]

Martin, Mills, et al., 1976
Martin, R.L.; Mills, B.E.; Shirley, D.A., Fluorine 1s correlation states in the photoionization of hydrogen fluoride: experiment and theory, J. Chem. Phys., 1976, 64, 3690. [all data]


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