Diffusion Monte Carlo (DMC) calculations of the spectroscopic properties of a large set of molecules were performed, assessing the effect of different approximations. In systems containing elements with large atomic numbers, we show that the errors associated with the use of nonlocal mean-field-based pseudopotentials in DMC calculations can be significant and may surpass the fixed-node error. We suggest practical guidelines for reducing these pseudopotential errors, which allow us to obtain DMC-computed spectroscopic parameters of molecules and equation of state properties of solids in excellent agreement with experiment.
Nazarov, Roman, et al. "Benchmarking the pseudopotential and fixed-node approximations in diffusion Monte Carlo calculations of molecules and solids." Physical Review B, vol. 93, no. 9, Mar. 2016. https://doi.org/10.1103/PhysRevB.93.094111
Nazarov, Roman, Shulenburger, Luke, Morales, Miguel A., & Hood, Randolph Q. (2016). Benchmarking the pseudopotential and fixed-node approximations in diffusion Monte Carlo calculations of molecules and solids. Physical Review B, 93(9). https://doi.org/10.1103/PhysRevB.93.094111
Nazarov, Roman, Shulenburger, Luke, Morales, Miguel A., et al., "Benchmarking the pseudopotential and fixed-node approximations in diffusion Monte Carlo calculations of molecules and solids," Physical Review B 93, no. 9 (2016), https://doi.org/10.1103/PhysRevB.93.094111
@article{osti_1261352,
author = {Nazarov, Roman and Shulenburger, Luke and Morales, Miguel A. and Hood, Randolph Q.},
title = {Benchmarking the pseudopotential and fixed-node approximations in diffusion Monte Carlo calculations of molecules and solids},
annote = {Diffusion Monte Carlo (DMC) calculations of the spectroscopic properties of a large set of molecules were performed, assessing the effect of different approximations. In systems containing elements with large atomic numbers, we show that the errors associated with the use of nonlocal mean-field-based pseudopotentials in DMC calculations can be significant and may surpass the fixed-node error. We suggest practical guidelines for reducing these pseudopotential errors, which allow us to obtain DMC-computed spectroscopic parameters of molecules and equation of state properties of solids in excellent agreement with experiment.},
doi = {10.1103/PhysRevB.93.094111},
url = {https://www.osti.gov/biblio/1261352},
journal = {Physical Review B},
issn = {ISSN 2469-9950},
number = {9},
volume = {93},
place = {United States},
publisher = {American Physical Society (APS)},
year = {2016},
month = {03}}
Lawrence Livermore National Laboratory (LLNL), Livermore, CA; Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
Sponsoring Organization:
USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC); USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22)