Theoretical study of the potential energy surfaces and dynamics of CaNC/CaCN

Potential energy surfaces for the ground and two low-lying electronically excited states of CaNC/ CaCN, are calculated using the ab initio molecular orbital (MO) configuration interaction (CI) method. The absorption and emission spectra of the system are computed by performing time-dependent quantum dynamical calculations on these surfaces. The most stable geometries for the two lowest lying 1(2) Sigma(+) and 1(2) Pi electronic states correspond to the calcium isocyanide (CaNC) structure. These two states are characterized by ionic bonding and the potential energy curves along the bending coordinate are relatively isotropic. The result of our wave packet dynamics shows that the characteristics of the experimental spectra observed by the laser-induced fluorescence spectroscopy can be explained by the Renner-Teller splitting. (C) 1997 American Institute of Physics.