COMPLEX DIAGONAL SHIFT FORMULA (CDSF) IN SCF ITERATIVE PROCESS

In this paper, we extend the diagonal shift formula (DSF) to complex diagonal shiftformula (CDSF) in a complex field, and give the theoretical proof of convergence.Meanwhile, when the variable degenerates from complex to real, the CDSF will becomeDSF, which indicates that the former is indeed the extension of the latter. The CDSF has already been applied to MNDO/GIAO and INDO/GIAO calculations ofNMR shielding constants which involve calculations of the complex Fock matrix. Overallconvergence of iterative process manifests that the CDSF is an effective method ofcomplex matrix iterations.