Analyzing molecular static linear response properties with perturbed localized orbitals.
Perturbed localized molecular orbitals (LMOs), correct to first order in an applied static perturbation and consistent with a chosen localization functional, are calculated using analytic derivative techniques. The formalism is outlined for a general static perturbation and variational localization functionals. Iterative and (formally) single-step approaches are compared. The implementation employs an iterative sequence of 2x2 orbital rotations. The procedure is verified by calculations of molecular electric-field perturbations. Boys LMO contributions to the electronic static polarizability and the electric-field perturbation of the r(2) expectation value are calculated and analyzed for ethene, ethyne, and fluoroethene (H(2)C=CHF). For ethene, a comparison is made with results from a Pipek-Mezey localization. The calculations show that a chemically intuitive decomposition of the calculated properties is possible with the help of the LMO contributions and that the polarizability contributions in similar molecules are approximately transferable.
Autschbach
Jochen
J
Department of Chemistry, State University of New York at Buffalo, New York 14260-3000, USA. jochena@buffalo.edu
King
Harry F
HF