SIZE-CONSISTENT SELF-CONSISTENT CONFIGURATION-INTERACTION FROM A COMPLETE ACTIVE SPACE - EXCITED-STATES

The self-consistent size consistent on a complete active space singly and doubly configuration interaction (SC)(2)CAS-SDCI method is applied to excited states. The (SC)(2) correction is performed on a closed sh ell state, and the excited states are obtained by diagonalization of t he dressed matrix. A theoretical justification of the transferability of the improvement concerning the dressing state to all roots of the m atrix is presented. The method is tested by three tests on the spectru m of small molecules. (C) 1998 American Institute of Physics. [S0021-9 606(98)30843-0].