T. Leininger et Gh. Jeung, AB-INITIO CALCULATION OF ROVIBRONIC TRANSITION SPECTRA OF CAH, The Journal of chemical physics, 103(10), 1995, pp. 3942-3949
The ground (1 (2) Sigma(+), X) and excited electronic states, 1 (2) Pi
(A), 2 (2) Sigma(+) (B,B'), 1 (2) Delta, 2 (2) Pi (E), 3 (2) Sigma(+)
(D), 4 (2) Sigma(+) (C), 5 (2) Sigma(+) (K), 3 (2) Pi (L), and 2 (2)
Delta, of CaH are studied by ab initio calculation, with extensive con
figuration interactions. Calculated spectroscopic constants, in partic
ular, the excitation energies, are more accurate than in previous calc
ulations and agree well with the currently available experimental data
. This work confirms the existence of a single vibrational level, v'=4
, bound to the second well of the B state calculated from the experime
ntal data by Martin [J. Chem. Phys. 88, 1797 (1988)]. Calculated oscil
lator strengths for the B-X and D-X show irregular band structures bec
ause of multiple avoided crossings of the potential energy curves. The
avoided crossing between the D and C states should be taken into acco
unt to explain the apparent perturbations observed in the experimental
spectra. The wave functions, dipole moments, and transition dipole mo
ments of these states are discussed in detail. (C) 1995 American Insti
tute of Physics.