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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 October, 1976

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 12C32S+
C 2Sigma+ 54120 1055 1          53960 1
Frost, Lee, et al., 1972
B 2Sigma+ 36470 868 1          36210 1
Frost, Lee, et al., 1972
A 2Pii 11990 2 1012.8 Z 6.52  0.71776 0.00622  0.00000182 0.00000015 1.6407 A rarrow X R 11806.3 Z
Horani, 1979
X 2Sigma+ 0 1384 3   [0.86400] 4   [0.00000126]  [1.4954]  


1From the photoelectron spectrum Frost, Lee, et al., 1972: see also Jonathan, Morris, et al., 1972.
2A = -298.46 Horani, 1979.
3From the photoelectron spectrum Frost, Lee, et al., 1972; Jonathan, Morris, et al., 1972 and King, Kroto, et al., 1972 give 1330 and 1290 cm-1, respectively. Only one level has been found in the optical spectrum Horani, 1979.
4Spin-splitting constant gamma0 = +0.0201.
5From a short extrapolation of the vibrational levels in A 1Sigma+ Bell, Ng, et al., 1972, assuming that the atomic products arising at the dissociation limit are C, 3P2 + S, 3P2. The latest thermochemical (mass-spectrometric) value is D00= 7.21 eV Hildenbrand, 1972. Both values agree with an upper limit (< 7.7 eV) derived from infrared chemiluminescence studies Hancock, Morley, et al., 1971, and the corresponding heats of formation, DeltaHof0 = 66.11 or 69.5 kcal/mole, respectively, are supported by photodissociation Okabe, 1972 and photoionization Dibeler and Walker, 1967 results for CS2. See, however, Hubin-Franskin, Locht, et al., 1976, Hubin-Franskin, Katihabwa, et al., 1976 who suggest DeltaHof0 = 33 kcal/mole, implying D00 = 8.79 eV.
6From the photoelectron spectrum Jonathan, Morris, et al., 1972, King, Kroto, et al., 1972, Frost, Lee, et al., 1972.
7Single weak absorption band.
8Bands described as diffuse.
9omegaeze = -0.0377.
10alphav= +0.00112(v+1/2)2 - 0.000208(v+1/2)3.
11Deperturbed constants Barrow, Dixon, et al., 1961; all observed vibrational levels of this state are strongly perturbed by interactions with a 3Pi, a' 3Sigma+, d 3Delta, e 3Sigma- Lagerqvist, Westerlund, et al., 1959, Barrow, Dixon, et al., 1961, Field and Bergeman, 1971. The following rather different set of deperturbed parameters is given by Cossart and Bergeman, 1976; Te = 38895.7 Cossart and Bergeman, 1976, omegae = 1077.3 Cossart and Bergeman, 1976, omegaexe = 10.66 Cossart and Bergeman, 1976, Be = 0.7881 Cossart and Bergeman, 1976, alphae = 0.0092 Cossart and Bergeman, 1976.
12Lambda-doubling intervals in v=0 (J=1-9) range from 0.00045 to 0.05961cm-1 Silvers, Bergeman, et al., 1970, Field and Bergeman, 1971. The variation with J of the Stark effect was observed in optical-rf double resonance and was analyzed Field and Bergeman, 1971 to give muel(v=0) = 0.63 D (+CS-); see also Silvers, Bergeman, et al., 1970.
13RKR potential functions Nair, Singh, et al., 1965.
14Lifetimes from Hanle effect observations tau(v=0) = 176 ns Silvers and Chiu, 1972 (corrected for lengthening by triplet mixing), tau(v=2) = 203 ns Silvers and Chiu, 1972. The phase shift method Smith, 1969 gives tau(v=0) = 255 ns Smith, 1969, tau(v=1) = 339 ns Smith, 1969, tau(v geq 2) = 292 ns Smith, 1969; f00 = 0.0059.
15Morse-potential Franck-Condon factors Felenbok, 1965: compare with experimental values from the fluorescence spectrum excited in the VUV photolysis of CS2 and OCS Lee and Judge, 1975. C34S isotopic bands Narasimham and Gopal, 1966, Chaudhry, Upadhya, et al., 1970.
16Only v=1 and 2 observed Barrow, Dixon, et al., 1961; the vibrational numbering is from isotope studies Field and Bergeman, 1971. The following set of deperturbed parameters is given by Cossart and Bergeman, 1976; Te = 38681.9, omegae = 752.8, omegaexe = 4.95, Be = 0.6227, alphae = 0.0062. Spin-splitting in v=1: lambda+1/2gamma = 1.75 Barrow, Dixon, et al., 1961.
17This state, originally Barrow, Dixon, et al., 1961, Field and Bergeman, 1971 considered to be 3Pi and labelled k, is now believed to be 3Delta Robbe and Schamps, 1972, Bruna, Kammer, et al., 1975. The name has been changed to d 3Delta in order to emphasize the similarity to CO. A ~ -50.
18Deperturbed constants Cossart and Bergeman, 1976.
19Spin-splitting constant lambda(v=10) = -1.28 Field and Bergeman, 1971.
20A ~ 95 cm-1.
21From Taylor, Setser, et al., 1972.
22Two subbands corresponding to 3Pi1 - 3Sigma+ and 3Pi0 - 3Sigma+ have been observed Taylor, Setser, et al., 1972.
23Dipole moments [-CS+, see McGurk, Tigleaar, et al., 1973] from Stark effect muel(v=0) = 1.958 D Winnewisser and Cook, 1968, muel(v=1) = 1.936 D Winnewisser and Cook, 1968. Zeeman effect McGurk, Tigleaar, et al., 1973, molecular g factor -0.2702. 32S/33S and 32S/34S mass ratios from microwave spectra Rosenblum, Townes, et al., 1958.
24D00(CS) + I.P.(S) - I.P.(CS).


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

Frost, Lee, et al., 1972
Frost, D.C.; Lee, S.T.; McDowell, C.A., The high resolution photoelectron spectrum of CS, Chem. Phys. Lett., 1972, 17, 153. [all data]

Horani, 1979
Horani, M., Unpublished cited in Huber and Herzberg, 1979, 1979, 187. [all data]

Jonathan, Morris, et al., 1972
Jonathan, N.; Morris, A.; Okuda, M.; Ross, K.J.; Smith, D.J., Photoelectron spectroscopy of transient species. The CS molecule, Faraday Discuss. Chem. Soc., 1972, 54, 48. [all data]

King, Kroto, et al., 1972
King, G.H.; Kroto, H.W.; Suffolk, R.J., The photoelectron spectrum of a short-lived species in the decomposition products of CS2, Chem. Phys. Lett., 1972, 13, 457. [all data]

Bell, Ng, et al., 1972
Bell, S.; Ng, T.L.; Suggitt, C., An emission system of CS in the vacuum and near ultraviolet, J. Mol. Spectrosc., 1972, 44, 267. [all data]

Hildenbrand, 1972
Hildenbrand, D.L., Thermochemistry of the molecules CS and CS+, Chem. Phys. Lett., 1972, 15, 379. [all data]

Hancock, Morley, et al., 1971
Hancock, G.; Morley, C.; Smith, I.W.M., Vibrational excitation of CO in the reaction: O + CS --> CO + S, Chem. Phys. Lett., 1971, 12, 193. [all data]

Okabe, 1972
Okabe, H., Photodissociation of CS2 in the vacuum ultraviolet; determination of D0° (SC-S), J. Chem. Phys., 1972, 56, 4381. [all data]

Dibeler and Walker, 1967
Dibeler, V.H.; Walker, J.A., Mass-spectrometric study of photoionization. VI. O2, CO2, COS, and CS2, J. Opt. Soc. Am., 1967, 57, 1007. [all data]

Hubin-Franskin, Locht, et al., 1976
Hubin-Franskin, M.-J.; Locht, R.; Katihabwa, J., Dissociative ionization of carbon disulphide in the gas phase. Heat of formation of the CS radical, Chem. Phys. Lett., 1976, 37, 488. [all data]

Hubin-Franskin, Katihabwa, et al., 1976
Hubin-Franskin, M.-J.; Katihabwa, J.; Collin, J.E., Dissociative electron attachment for the carbonyl sulphide molecule in the gas phase. Heat of formation of the CS radical, Int. J. Mass Spectrom. Ion Phys., 1976, 20, 285. [all data]

Barrow, Dixon, et al., 1961
Barrow, R.F.; Dixon, R.N.; Lagerqvist, A.; Wright, C.V., Rotational analysis of the absorption spectrum of carbon monosulphide, Ark. Fys., 1961, 18, 543. [all data]

Lagerqvist, Westerlund, et al., 1959
Lagerqvist, A.; Westerlund, H.; Wright, C.V.; Barrow, R.F., Rotational analysis of the ultraviolet band system of CS, Ark. Fys., 1959, 14, 387. [all data]

Field and Bergeman, 1971
Field, R.W.; Bergeman, T.H., Radio-frequency spectroscopy and perturbation analysis in CS A1«PI»(v=O), J. Chem. Phys., 1971, 54, 2936. [all data]

Cossart and Bergeman, 1976
Cossart, D.; Bergeman, T., Off-diagonal spin-orbit and apparent spin-spin parameters in carbon monosulfide, J. Chem. Phys., 1976, 65, 5462-5468. [all data]

Silvers, Bergeman, et al., 1970
Silvers, S.J.; Bergeman, T.H.; Klemperer, W., Level crossing and double resonance on the A1«PI» state of CS, J. Chem. Phys., 1970, 52, 4385. [all data]

Nair, Singh, et al., 1965
Nair, K.P.R.; Singh, R.B.; Rai, D.K., Potential-energy curves and dissociation energies of oxides and sulfides of group IV A elements, J. Chem. Phys., 1965, 43, 3570. [all data]

Silvers and Chiu, 1972
Silvers, S.J.; Chiu, C.-L., Hanle effect measurement of the lifetime of the A1«PI» state of CS, J. Chem. Phys., 1972, 56, 5663. [all data]

Smith, 1969
Smith, W.H., Absolute transition probabilities for some electronic states of CS, SO and S2, J. Quant. Spectrosc. Radiat. Transfer, 1969, 9, 1191. [all data]

Felenbok, 1965
Felenbok, P., Franck-Condon factors and r centroids for A1«PI» - X1«SIGMA»+ system of CS, Proc. Phys. Soc. London, 1965, 86, 676. [all data]

Lee and Judge, 1975
Lee, L.C.; Judge, D.L., CS(A1«PI» --> X1«SIGMA»+) fluorescence from photodissociation of CS2 and OCS, J. Chem. Phys., 1975, 63, 2782. [all data]

Narasimham and Gopal, 1966
Narasimham, N.A.; Gopal, K.S., Isotope shifts (C32S-C34S) in the bands of the A1«PI»-X1«SIGMA»+ system of CS, Curr. Sci., 1966, 35, 485. [all data]

Chaudhry, Upadhya, et al., 1970
Chaudhry, A.K.; Upadhya, K.N.; Thakur, S.N., Rotational structure in the 1«PI»-1«SIGMA»+ transition of CS34 molecule, Indian J. Phys., 1970, 44, 375. [all data]

Robbe and Schamps, 1972
Robbe, J.M.; Schamps, J., The nature of the k state of CS, Chem. Phys. Lett., 1972, 15, 596. [all data]

Bruna, Kammer, et al., 1975
Bruna, P.J.; Kammer, W.E.; Vasudevan, K., Vertical electronic spectrum of CS molecule, Chem. Phys., 1975, 9, 91. [all data]

Taylor, Setser, et al., 1972
Taylor, G.W.; Setser, D.W.; Coxon, J.A., The emission spectrum of CS(a3«PI» --> X1«SIGMA»+) excited by interaction of CS containing molecules with metastable argon atoms, J. Mol. Spectrosc., 1972, 44, 108. [all data]

McGurk, Tigleaar, et al., 1973
McGurk, J.; Tigleaar, H.L.; Rock, S.L.; Norris, C.L.; Flygare, W.H., Detection assignment of the microwave spectrum and the molecular Stark and Zeeman effects in CSe, and the Zeeman effect and sign of the dipole moment in CS, J. Chem. Phys., 1973, 58, 1420. [all data]

Winnewisser and Cook, 1968
Winnewisser, G.; Cook, R.L., The dipole moment of carbon monosulfide, J. Mol. Spectrosc., 1968, 28, 266. [all data]

Rosenblum, Townes, et al., 1958
Rosenblum, B.; Townes, C.H.; Geschwind, S., Recent determinations of atomic mass ratios by microwave spectroscopy, Rev. Mod. Phys., 1958, 30, 409. [all data]

Huber and Herzberg, 1979
Huber, K.P.; Herzberg, G., Molecular Spectra and Molecular Structure. IV. Constants of Diatomic Molecules, Van Nostrand Reinhold Company, New York, 1979, 716. [all data]


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