Electronic states of SiC−: A theoretical study

Multireference singles and doubles configuration interaction calculations are performed to study the electronic structure and spectroscopic properties of SiC−. Potential energy curves and spectroscopic parameters of 21 low-lying doublets, quartets, and sextets within 6 eV are determined. Two strong transitions, C2Π-X2Σ+ and D2Π-X2Σ+ with band origins around 22 300 and 23 550 cm−1, respectively are predicted for the first time. The partial radiative lifetimes for these transitions are estimated. Dipole moments of some of the low-lying states are calculated by keeping the origin at the center of mass. The vertical and adiabatic electron affinities of SiC are also reported.