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arXiv · 1707.09439

Charge-transfer excited states: Seeking a balanced and efficient wave function ansatz in variational Monte Carlo

N. S. Blunt·Eric Neuscamman
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Abstract

We present a simple and efficient wave function ansatz for the treatment of excited charge-transfer states in real-space quantum Monte Carlo methods. Using the recently-introduced variation-after-response method [J. Chem. Phys. 145, 081103 (2016)], this ansatz allows a crucial orbital optimization step to be performed beyond a configuration interaction singles expansion, while only requiring calculation of two Slater determinant objects. We demonstrate this ansatz for the illustrative example of the stretched LiF molecule, for a range of excited states of formaldehyde, and finally for the more challenging ethylene-tetrafluoroethylene molecule.

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N. S. Blunt, Eric Neuscamman. 2017-07-28. Charge-transfer excited states: Seeking a balanced and efficient wave function ansatz in variational Monte Carlo. https://doi.org/10.1063/1.4998197

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