A time-dependent formulation of multi-reference perturbation theory

Alexander Yu. Sokolov; Garnet K. -L. Chan

doi:10.1063/1.4941606

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arXiv · 1512.09213

A time-dependent formulation of multi-reference perturbation theory

Alexander Yu. Sokolov·Garnet K. -L. Chan

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Abstract

We discuss the time-dependent formulation of perturbation theory in the context of the interacting zeroth-order Hamiltonians that appear in multi-reference situations. As an example, we present a time-dependent formulation and implementation of second-order n-electron valence perturbation theory. The resulting t-NEVPT2 method yields the fully uncontracted n-electron valence perturbation wavefunction and energy, but has a lower computational scaling than the usual contracted variants, and also avoids the construction of high-order density matrices and the diagonalization of metrics. We present results of t-NEVPT2 for the water, nitrogen, carbon, and chromium molecules, and outline directions for the future.

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Alexander Yu. Sokolov, Garnet K. -L. Chan. 2016-01-27. A time-dependent formulation of multi-reference perturbation theory. https://doi.org/10.1063/1.4941606

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