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arXiv · 2009.13556

Excited states in variational Monte Carlo using a penalty method

Shivesh Pathak·Brian Busemeyer·João N. B. Rodrigues·Lucas K. Wagner
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Abstract

The authors present a technique using variational Monte Carlo to solve for excited states of electronic systems. The technique is based on enforcing orthogonality to lower energy states, which results in a simple variational principle for the excited states. Energy optimization is then used to solve for the excited states. This technique is applied to the well-characterized benzene molecule, in which $\sim$10,000 parameters are optimized for the first 12 excited states. Agreement within approximately 0.2 eV is obtained with higher scaling coupled cluster methods; small disagreements with experiment are likely due to vibrational effects.

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Shivesh Pathak, Brian Busemeyer, João N. B. Rodrigues, Lucas K. Wagner. 2020-09-28. Excited states in variational Monte Carlo using a penalty method. https://doi.org/10.1063/5.0030949

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