A variational method for the calculation of spin-rovibronic energy levels of any triatomic molecule in an electronic triplet state

Carter, S., Handy, N.C. and Tarroni., R. (2005) A variational method for the calculation of spin-rovibronic energy levels of any triatomic molecule in an electronic triplet state. Molecular Physics, 103 (6-8). pp. 1131-1137. ISSN 0026-8976 doi: 10.1080/00268970412331332961

Abstract/Summary

The triatomic spin-rovibronic variational code RVIB3 has been extended to include the effect of two uncoupled electrons, for both (3)Sigma(-) and (3)Pi (Renner-Teller) electronic states. The spin-orbital-rotational kinetic energy is included in the usual way, via terms (J+L+S). The phenomenological terms AL.S and lambda 2/3(3S(z)(2)) are introduced to reproduce the 3 spin-orbit and spin-spin splittings, respectively. Calculations are performed to evaluate the spin-rovibronic energy levels of CCO (X) over tilde (3) Sigma(-) and CCO (A) over tilde (3) Pi for which the Born-Oppenheimer potentials are derived from high-accuracy ab initio calculations.