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arXiv · 1509.07467

Binding Energies from Diffusion Monte Carlo for the MB-pol H_2O and D_2O Dimer: A Comparison to Experimental Values

Joel Mallory·Vladimir Mandelshtam
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Abstract

The Diffusion Monte Carlo (DMC) method is applied to compute the ground state energies of the water monomer and dimer and their D 2 O isotopomers using MB-pol; the most recent and most accurate ab inito- based potential energy surface (PES). MB-pol has already demonstrated excellent agreement with high level electronic structure data, as well as agreement with some experimental, spectroscopic, and thermodynamic data. Here, the DMC binding energies of (H 2 O) 2 and (D 2 O) 2 agree with the corresponding values obtained from velocity map imaging within, respectively, 0.01 and 0.02 kcal/mol. This work adds two more valuable data points that highlight the accuracy of the MB-pol PES.

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Joel Mallory, Vladimir Mandelshtam. 2015-09-24. Binding Energies from Diffusion Monte Carlo for the MB-pol H_2O and D_2O Dimer: A Comparison to Experimental Values. https://doi.org/10.1063/1.4932596

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