Linear-scaling implementation of molecular response theory in self-consistent field electronic-structure theory
2007 (English)In: Journal of Chemical Physics, ISSN 0021-9606, E-ISSN 1089-7690, Vol. 126, no 15, 11930-11935 p.Article in journal (Refereed) Published
A linear-scaling implementation of Hartree-Fock and Kohn-Sham self-consistent field theories for the calculation of frequency-dependent molecular response properties and excitation energies is presented, based on a nonredundant exponential parametrization of the one-electron density matrix in the atomic-orbital basis, avoiding the use of canonical orbitals. The response equations are solved iteratively, by an atomic-orbital subspace method equivalent to that of molecular-orbital theory. Important features of the subspace method are the use of paired trial vectors (to preserve the algebraic structure of the response equations), a nondiagonal preconditioner (for rapid convergence), and the generation of good initial guesses (for robust solution). As a result, the performance of the iterative method is the same as in canonical molecular-orbital theory, with five to ten iterations needed for convergence. As in traditional direct Hartree-Fock and Kohn-Sham theories, the calculations are dominated by the construction of the effective Fock/Kohn-Sham matrix, once in each iteration. Linear complexity is achieved by using sparse-matrix algebra, as illustrated in calculations of excitation energies and frequency-dependent polarizabilities of polyalanine peptides containing up to 1400 atoms.
Place, publisher, year, edition, pages
2007. Vol. 126, no 15, 11930-11935 p.
density-matrix, hartree-fock, direct optimization, equations
IdentifiersURN: urn:nbn:se:kth:diva-16570DOI: 10.1063/1.2715568ISI: 000245870900009ScopusID: 2-s2.0-34247389281OAI: oai:DiVA.org:kth-16570DiVA: diva2:334612
QC 201005252010-08-052010-08-05Bibliographically approved