Author/Authors :
Yamamoto، نويسنده , , Naoko and Vreven، نويسنده , , Thom and Robb، نويسنده , , Michael A. and Frisch، نويسنده , , Michael J. and Bernhard Schlegel، نويسنده , , H.، نويسنده ,
Abstract :
A direct method for the computation of energy second derivatives, and first derivatives which require the solution of the coupled perturbed MC-SCF equations, is presented. The two-electron derivative integral transformation is formulated in terms of 3/4 transformed integrals. The optimum strategy for the solution of the CP-MCSCF linear equations involves the solution in a Krylov space that involves all the right-hand sides. The feasibility of the method is demonstrated in a computation on the excited states of indene, styrene and octatetraene.
