AB-INITIO COUPLED-CLUSTER STUDY OF (2)PI RADICALS IN-GROUND AND EXCITED-STATES - APPLICATION TO NCO AND NCS

In this paper we report EOM-CC (equation-of-motion coupled-cluster) ca lculations on the <(X)over tilde (2) Pi> and <(B)over tilde (2) Pi> st ates of NCO and NCS radicals. Equilibrium bond length, rotational cons tant, harmonic vibrational frequencies, Renner-Teller parameter and sp in-orbit splitting values are presented and compared to the available experimental data. The results show clearly that the calculated molecu lar parameters are accurate enough to be used in assigning experimenta l spectra. (C) 1997 Elsevier Science B.V.