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Ab-initio path integral techniques for molecules

Daejin Shin·Ming-Chak Ho·J. Shumway
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Abstract

Path integral Monte Carlo with Green's function analysis allows the sampling of quantum mechanical properties of molecules at finite temperature. While a high-precision computation of the energy of the Born-Oppenheimer surface from path integral Monte Carlo is quite costly, we can extract many properties without explicitly calculating the electronic energies. We demonstrate how physically relevant quantities, such as bond-length, vibrational spectra, and polarizabilities of molecules may be sampled directly from the path integral simulation using Matsubura (temperature) Green's functions (imaginary-time correlation functions). These calculations on the hydrogen molecule are a proof-of-concept, designed to motivate new work on fixed-node path-integral calculations for molecules.

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Daejin Shin, Ming-Chak Ho, J. Shumway. 2006-11-09. Ab-initio path integral techniques for molecules. https://arxiv.org/abs/quant-ph/0611105

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