Excited state geometry optimization with the density matrix renormalization group as applied to polyenes

Weifeng Hu; Garnet Kin-Lic Chan

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arXiv · 1502.07731

Excited state geometry optimization with the density matrix renormalization group as applied to polyenes

Weifeng Hu·Garnet Kin-Lic Chan

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Abstract

We describe and extend the formalism of state-specific analytic density matrix renormalization group (DMRG) energy gradients, first used by Liu et al (J. Chem. Theor.Comput. 9, 4462 (2013)). We introduce a DMRG wavefunction maximum overlap following technique to facilitate state-specific DMRG excited state optimization. Using DMRG configuration interaction (DMRG-CI) gradients we relax the low-lying singlet states of a series of trans-polyenes up to C20H22. Using the relaxed excited state geometries as well as correlation functions, we elucidate the exciton, soliton, and bimagnon ("single-fission") character of the excited states, and find evidence for a planar conical intersection.

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Weifeng Hu, Garnet Kin-Lic Chan. 2015-02-26. Excited state geometry optimization with the density matrix renormalization group as applied to polyenes. https://arxiv.org/abs/1502.07731

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