title: Implementation of Analytical Energy Gradient of Spin-Dependent General Hartree-Fock Method Based on the Infinite-Order Douglas-Kroll-Hess Relativistic Hamiltonian with Local Unitary Transformation.
abstract: An analytical energy gradient for the spin-dependent general Hartree-Fock method based on the infinite-order Douglas-Kroll-Hess (IODKH) method was developed. To treat realistic systems, the local unitary transformation (LUT) scheme was employed both in energy and energy gradient calculations. The present energy gradient method was numerically assessed to investigate the accuracy in several diatomic molecules containing fifth- and sixth-period elements and to examine the efficiency in one-, two-, and three-dimensional silver clusters. To arrive at a practical calculation, we also determined the geometrical parameters of fac-tris(2-phenylpyridine)iridium and investigated the efficiency. The numerical results confirmed that the present method describes a highly accurate relativistic effect with high efficiency. The present method can be a powerful scheme for determining geometries of large molecules, including heavy-element atoms.
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University , Tokyo 169-8555, Japan.
authors.forename: Yuya
authors.initials: Y
authors.lastname: Nakajima
authors.affiliation: Research Institute for Science and Engineering, Waseda University , Tokyo 169-8555, Japan.
authors.forename: Junji
authors.initials: J
authors.lastname: Seino
authors.affiliation: Department of Chemistry and Biochemistry, School of Advanced Science and Engineering, Waseda University , Tokyo 169-8555, Japan.|Research Institute for Science and Engineering, Waseda University , Tokyo 169-8555, Japan.|CREST, Japan Science and Technology Agency, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan.|Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University , Katsura, Kyoto 615-8520, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Nakai