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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 May, 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 14N32S+
Bands previously Dressler, 1955 attributed to NS+ have been reclassified by Jenouvrier and Pascat, 1973 as G rarrow X system of NS
X 1Sigma+ 0 1415 1 15       1.440  
missing citation


1Vibrational constants from the photoelectron spectrum 30.
2Estimate based on a linear Birge-Sponer extrapolation for the ground state O'Hare, 1970. Ab initio calculations O'Hare, 1970 give 5.2 eV.
3From the photoelectron spectrum Dyke, Morris, et al., 1977.
4Intensity perturbations and predissociations in both doublet components.
5Only fragments observed.
6Approximate deperturbed constants, A ~ +45. This level is strongly perturbed by v=11 of H 2Pii (B11 = 0.525, A11 = -110).
7Spin doubling constant gamma0 ~ +0.1 for N leq ~20. The spin splitting increases rapidly at higher N because of a perturbation by H 2Pi(v=1). I 2Sigma+(v=1) (B1 ~ 0.695) interacts with H 2Pi(v=2) at somewhat lower N values. A strong homogeneous interaction with levels of C 2Sigma+ explains the larger than expected DeltaG(1/2) value of I 2Sigma+.
8A0 = -172.3.
9Perturbations by levels of E, I, C; see 6,7,10.
10DeltaG(3/2) = 1414 Vervloet and Jenouvrier, 1976, DeltaG(5/2) ~ 1372, DeltaG(7/2) ~ 1378 Joshi, 1966. B1 ~ 0.7975 Vervloet and Jenouvrier, 1976, B2 ~ 0.8150 Vervloet and Jenouvrier, 1976; Balasubramanian and Narasimham, 1974 give B0 = 0.82876 Balasubramanian and Narasimham, 1974 and D0 = 1.404~E-6 Balasubramanian and Narasimham, 1974 as well as gamma0 = +0.0055 Balasubramanian and Narasimham, 1974. C 2Sigma+ interacts strongly with I 2Sigma+; in addition, v=1 is extensively perturbed by H 2Pi(v=2) and G 2Sigma-(v=2).
11Estimated lifetime tau(v=0) ~ 6.5 ns [Hanle effect measurements Silvers and Chiu, 1974].
12Observed in absorption by Donovan and Breckenridge, 1971 following the flash photolysis of OCS in the presence of excess N2O.
13Spin doubling constant gamma0 = +0.034.
14B1 = 0.6780.
15The A state is strongly perturbed, particularly the 2Delta5/2 component [see Jenouvrier and Pascat, 1973]; the DeltaG(1/2) values are from missing citation, omegaexe from Narasimham and Srikameswaran, 1963, and B0 from Jenouvrier and Pascat, 1973. Additional constants may be found in these references but, because of the perturbations, have limited meaning. Jenouvrier and Pascat, 1973 suggest that the perturbing state is 2Phi5/2.
16Only the 1-0 band has been observed and analyzed (B1 = 0.7716, v0 = 372023.9 and 36982.5). The v=0 level of 14N32S interacts with B 2Pi1/2(v=8) Jenouvrier and Daumont, 1976; weak emission from this level was observed for 15N32S Jenouvrier and Daumont, 1976.
17Several perturbations. Except for v=8 (see 16), these interactions have not yet been analyzed.
18A0 = +222.94 Amano, Saito, et al., 1969, A1 = +223.09 Amano, Saito, et al., 1969, recalculated by Amano, Saito, et al., 1969 from the data of Zeeman, 1951.
19Lambda-type doubling, Delta nufe = +0.013253(J+1/2) Amano, Saito, et al., 1969.
20muel(2Pi1/2,v=0) = 1.81 D Amano, Saito, et al., 1969 from Stark effect measurements in the rotation spectrum Amano, Saito, et al., 1969; Carrington, Howard, et al., 1968, using the EPR method, obtained muel(2Pi3/2,v=0)= 1.35 D Carrington, Howard, et al., 1968. This value was recently revised to muel (2Pi3/2, v=0)= 1.86 D Byfleet, Carrington, et al., 1971. See also O'Hare, 1970. Hyperfine coupling constants Carrington, Howard, et al., 1968, Amano, Saito, et al., 1969, Uehara and Morino, 1969.
21D00(NS) + I.P.(S) I.P.(NS).
22Estimated value from a Franck-Condon factor analysis of the photoelectron peaks Dyke, Morris, et al., 1977.


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

Dressler, 1955
Dressler, K., Ultraviolett- und Schumannspektren der neutralen und ionisierten Molekule PO, PS, NS, P2, Helv. Phys. Acta, 1955, 28, 563. [all data]

Jenouvrier and Pascat, 1973
Jenouvrier, A.; Pascat, B., Etats de valence de NS dans le domaine 2250-3800 Å, Can. J. Phys., 1973, 51, 2143. [all data]

O'Hare, 1970
O'Hare, P.A.G., Dissociation energies, enthalpies of formation, ionization potentials, and dipole moments of NS and NS+, J. Chem. Phys., 1970, 52, 2992. [all data]

Dyke, Morris, et al., 1977
Dyke, J.M.; Morris, A.; Trickle, I.R., Characterization of the ground ionic state of the NS molecule using photoelectron spectroscopy, J. Chem. Soc. Faraday Trans. 2, 1977, 73, 147. [all data]

Vervloet and Jenouvrier, 1976
Vervloet, M.; Jenouvrier, A., Etats Rydberg de NS. Etude du domaine spectral 2400-1750 Å, Can. J. Phys., 1976, 54, 1909. [all data]

Joshi, 1966
Joshi, K.C., The emission spectrum of the NS molecule, Z. Phys., 1966, 191, 126. [all data]

Balasubramanian and Narasimham, 1974
Balasubramanian, T.K.; Narasimham, N.A., Reinvestigation of the «beta» and the «gamma» band systems of NS, J. Mol. Spectrosc., 1974, 53, 128. [all data]

Silvers and Chiu, 1974
Silvers, S.J.; Chiu, C.-L., Fluorescence and zero-field level crossing spectroscopy of the C2«SIGMA»+ state of NS, J. Chem. Phys., 1974, 61, 1475. [all data]

Donovan and Breckenridge, 1971
Donovan, R.J.; Breckenridge, W.H., Reaction of S(31D2) with N2O, Chem. Phys. Lett., 1971, 11, 520. [all data]

Narasimham and Srikameswaran, 1963
Narasimham, N.A.; Srikameswaran, K., The «beta»- and «gamma»-band systems of 14NS and 15NS, Proc. Indian Acad. Sci. Sect. A, 1963, 56, 316. [all data]

Jenouvrier and Daumont, 1976
Jenouvrier, A.; Daumont, D., The B'2«SIGMA»+ state of NS, J. Mol. Spectrosc., 1976, 61, 313. [all data]

Amano, Saito, et al., 1969
Amano, T.; Saito, S.; Hirota, E.; Morino, Y., Hyperfine interactions and «lambda»-type doubling in the microwave spectrum of the NS radical, J. Mol. Spectrosc., 1969, 32, 97. [all data]

Zeeman, 1951
Zeeman, P.B., Rotational analysis of the «gamma» band system of the NS molecule, Can. J. Phys., 1951, 29, 174. [all data]

Carrington, Howard, et al., 1968
Carrington, A.; Howard, B.J.; Levy, D.H.; Robertson, J.C., Gas phase electron resonance spectrum of NS, Mol. Phys., 1968, 15, 187. [all data]

Byfleet, Carrington, et al., 1971
Byfleet, C.R.; Carrington, A.; Russell, D.K., Electric dipole moments of open-shell diatomic molecules, Mol. Phys., 1971, 20, 271. [all data]

Uehara and Morino, 1969
Uehara, H.; Morino, Y., Molecular structure of the NS free radical by gas-phase electron paramagnetic resonance, Mol. Phys., 1969, 17, 239. [all data]


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