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Multireference Perturbation Theory with Cholesky Decomposition for the Density Matrix Renormalization Group.

ABSTRACT: We present a second-order N-electron valence state perturbation theory (NEVPT2) based on a density matrix renormalization group (DMRG) reference wave function that exploits a Cholesky decomposition of the two-electron repulsion integrals (CD-DMRG-NEVPT2). With a parameter-free multireference perturbation theory approach at hand, the latter allows us to efficiently describe static and dynamic correlation in large molecular systems. We demonstrate the applicability of CD-DMRG-NEVPT2 for spin-state energetics of spin-crossover complexes involving calculations with more than 1000 atomic basis functions. We first assess, in a study of a heme model, the accuracy of the strongly and partially contracted variant of CD-DMRG-NEVPT2 before embarking on resolving a controversy about the spin ground state of a cobalt tropocoronand complex.

SUBMITTER: Freitag L

PROVIDER: S-EPMC5312874 | biostudies-literature | 2017 Feb

REPOSITORIES: biostudies-literature

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Multireference Perturbation Theory with Cholesky Decomposition for the Density Matrix Renormalization Group.

Freitag Leon L Knecht Stefan S Angeli Celestino C Reiher Markus M

Journal of chemical theory and computation 20170202 2

We present a second-order N-electron valence state perturbation theory (NEVPT2) based on a density matrix renormalization group (DMRG) reference wave function that exploits a Cholesky decomposition of the two-electron repulsion integrals (CD-DMRG-NEVPT2). With a parameter-free multireference perturbation theory approach at hand, the latter allows us to efficiently describe static and dynamic correlation in large molecular systems. We demonstrate the applicability of CD-DMRG-NEVPT2 for spin-state ...[more]

PMID: 28094988

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