Correct quantum chemistry in a minimal basis from effective Hamiltonians

Thomas J. Watson Jr.; Garnet Kin-Lic Chan

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arXiv · 1502.04698

Correct quantum chemistry in a minimal basis from effective Hamiltonians

Thomas J. Watson Jr.·Garnet Kin-Lic Chan

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Abstract

We describe how to create ab-initio effective Hamiltonians that qualitatively describe correct chemistry even when used with a minimal basis. The Hamiltonians are obtained by folding correlation down from a large parent basis into a small, or minimal, target basis, using the machinery of canonical transformations. We demonstrate the quality of these effective Hamiltonians to correctly capture a wide range of excited states in water, nitrogen, and ethylene, and to describe ground and excited state bond-breaking in nitrogen and the chromium dimer, all in small or minimal basis sets.

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Thomas J. Watson Jr., Garnet Kin-Lic Chan. 2015-02-16. Correct quantum chemistry in a minimal basis from effective Hamiltonians. https://arxiv.org/abs/1502.04698

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