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Sodium hydride

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 March, 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 23NaH
Extensive theoretical calculations have been made of X 1Sigma+ Cade and Huo, 1967 Sachs, Hinze, et al., 1975 Meyer and Rosmus, 1975 [see also Varshni and Shukla, 1963 Cade, Bader, et al., 1969] and of A 1Sigma+, B 1Pi, a 3Sigma+, b 3Pi, c 3Sigma+ Sachs, Hinze, et al., 1975; B, a, and c are predicted to be unstable. The calculations of Sachs, Hinze, et al., 1975 include transition moments, band strengths, line strengths, and the farwing broadening of the sodium D line; see also Watson, Stewart, et al., 1976. Additional higher excited states have been computed by Numrich and Truhlar, 1975.
b 3Pi (30940) 1 (419) 1 (50) 1  (3.53) 1 (0.85) 1    (2.22) 1  
A 1Sigma+ 22719 310.6 $cZ   1.696 2   2.27E-4 3  3.209 A lrarrow X 4 R 22294.5 Z
missing citation; missing citation; Olsson, 1935; Pankhurst, 1949
X 1Sigma+ 0 1172.2 Z 19.72 5 0.160 4.9012 0.1353 6  3.32E-4 6  1.8874  


1Theoretical predictions of Sachs, Hinze, et al., 1975 who feel, however, that the true potential of this state is considerably deeper than the calculated potential curve.
2B1= 1.823, B2= 1.875, B3= 1.908, B4= 1.930, B5= 1.938, B6= 1.941, B7= 1.936 Pankhurst, 1949.
3He ~ +5.7E-8 Pankhurst, 1949; both Dv and Hv decrease with increasing v.
4Radiative lifetimes tau(v'=3;J'=8) = 24.0 ns, tau(4;11) = 28.3 ns; tau(5;16) = 27.1 ns Baltayan, Jourdan, et al., 1976; tau(8;3) = 22.7 ns Dagdigian, 1976.
5omegaeze = -0.005 Pankhurst, 1949.
6Rotational constants from Olsson, 1935, betae = -0.03E-4. Pankhurst, 1949 gives Be = 4.886, alphae = 0.129, De ~ 3.15E-4, He ~ +1.7E-8 but includes only levels with v" geq 3.
7Theoretica1 value as modified by Meyer and Rosmus, 1975; the computational results are De0 = 1.92 Meyer and Rosmus, 1975 and 1.88 eV Sachs, Hinze, et al., 1975. Extrapolation of the ground state vibrational levels suggests 2.1 eV.
8Anomalous potential curve [an RKR curve has been constructed by Jain and Sah, 1963]; DeltaG(3/2)= 329.9, DeltaG(5/2)= 337.2, DeltaG(7/2)= 343.7, DeltaG(9/2)= 349.6, DeltaG(11/2)= 353.9, DeltaG(13/2)= 357.4, DeltaG(15/2)= 359.2, DeltaG(17/2)= 360.3, DeltaG(19/2)= 360.1, DeltaG(21/2)= 359.5, DeltaG(23/2)= 357.7, DeltaG(25/2)= 354.3, DeltaG(27/2)= 352.3, DeltaG(29/2)= 348.4, DeltaG(31/2)= 343.9, DeltaG(33/2)= 340.0,DeltaG(35/2)= 333.7, DeltaG(37/2)= 330.0, DeltaG(39/2)= 323.7 [from band origins Pankhurst, 1949].
9DeltaG(15/2)= 255.05, DeltaG(17/2)= 256.92, DeltaG(19/2)= 258.48, DeltaG(21/2)= 259.39, DeltaG(23/2)= 260.04, DeltaG(25/2)= 260.22, DeltaG(27/2)= 260.08, DeltaG(29/2)= 259.61, DeltaG(31/2)= 258.85, DeltaG(33/2)= 257.6 (from band origins).
10B7= 1.010, B8= 1.012, B9= 1.012, B10= 1.010, B11= 1.007, B12= 1.003, B13= 0.998, B14= 0.991, B15= 0.984, B16= 0.975, B17= 0.95.
11D7...Dl7 = 0.53E-4...0.44E-4.


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

Cade and Huo, 1967
Cade, P.E.; Huo, W.M., Electronic structure of diatomic molecules. VII.A. Hartree-Fock wavefunctions and energy quantities for the ground states of the second-row hydrides, AH, J. Chem. Phys., 1967, 47, 649. [all data]

Sachs, Hinze, et al., 1975
Sachs, E.S.; Hinze, J.; Sabelli, N.H., MCSCF calculations for six states of NaH, J. Chem. Phys., 1975, 62, 3367. [all data]

Meyer and Rosmus, 1975
Meyer, W.; Rosmus, P., PNO-Cl and CEPA studies of electron correlation effects. III. Spectroscopic constants and dipole moment functions for the ground states of the first-row and second-row diatomic hydrides, J. Chem. Phys., 1975, 63, 2356. [all data]

Varshni and Shukla, 1963
Varshni, Y.P.; Shukla, R.C., Alkali hydride molecules: potential energy curves and the nature of their binding, Rev. Mod. Phys., 1963, 35, 130. [all data]

Cade, Bader, et al., 1969
Cade, P.E.; Bader, R.F.W.; Henneker, W.H.; Keaveny, I., Molecular charge distributions and chemical binding. IV. The second-row diatomic hydrides AH, J. Chem. Phys., 1969, 50, 5313. [all data]

Watson, Stewart, et al., 1976
Watson, D.K.; Stewart, R.F.; Dalgarno, A., Variational time-dependent Hartree-Fock calculations. A pseudopotential study of the alkali metal hydrides, Mol. Phys., 1976, 32, 1661. [all data]

Numrich and Truhlar, 1975
Numrich, R.W.; Truhlar, D.G., Mixing of ionic and covalent configurations for NaH, KH, and MgH+. Potential energy curves and couplings between molecular states, J. Phys. Chem., 1975, 79, 2745. [all data]

Olsson, 1935
Olsson, E., Das absorptionsspektrum des NaD, Z. Phys., 1935, 93, 206. [all data]

Pankhurst, 1949
Pankhurst, R.C., The emission spectrum of sodium hydride, Proc. Phys. Soc. London Sect. A, 1949, 62, 191. [all data]

Baltayan, Jourdan, et al., 1976
Baltayan, P.; Jourdan, A.; Nedelec, O., Radiative lifetime of NaH A1«SIGMA»+ in a high frequency discharge, Phys. Lett. A, 1976, 58, 443. [all data]

Dagdigian, 1976
Dagdigian, P.J., Detection of LiH and NaH molecular beams by laser fluorescence and measurement of radiative lifetimes of the A1«SIGMA»+ state, J. Chem. Phys., 1976, 64, 2609. [all data]

Jain and Sah, 1963
Jain, D.C.; Sah, P., Potential-energy curves of the excited states of alkali hydride molecules, J. Chem. Phys., 1963, 38, 1553. [all data]


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