We here develop a fully quantum embedded version of initiator full configuration interaction quantum Monte Carlo (i–FCIQMC) and apply it to study an ionic bond (lithium hydride, LiH) and a covalent bond (hydrogen flouride, HF) physisorbed to a benzene molecule. The embedding is performed using a recently developed Huzinaga projection operator approach, which affords good synergy with i–FCIQMC by minimizing the number of orbitals in the calculation. When considering the dissociation energy of these bonds into closed-shell ionic fragments, we find that i–FCIQMC embedded in density functional theory (i–FCIQMC-in-DFT) delivers comparable accuracy with coupled cluster singles and doubles with perturbative triples embedded in density functional theory (CCSD(T)-in-DFT). In treating the bond dissociation energy curve of HF, i–FCIQMC-in-DFT has improved accuracy over CCSD(T)-in-DFT due to the presence of strong correlation. Lastly, we discuss the implications of the new i–FCIQMC-in-DFT method as applied to bond breaking in catalysis.
Petras, Hayley R., et al. "Fully Quantum Embedding with Density Functional Theory for Full Configuration Interaction Quantum Monte Carlo." Journal of Chemical Theory and Computation, vol. 15, no. 10, Aug. 2019. https://doi.org/10.1021/acs.jctc.9b00571
Petras, Hayley R., Graham, Daniel S., Ramadugu, Sai Kumar, Goodpaster, Jason D., & Shepherd, James J. (2019). Fully Quantum Embedding with Density Functional Theory for Full Configuration Interaction Quantum Monte Carlo. Journal of Chemical Theory and Computation, 15(10). https://doi.org/10.1021/acs.jctc.9b00571
Petras, Hayley R., Graham, Daniel S., Ramadugu, Sai Kumar, et al., "Fully Quantum Embedding with Density Functional Theory for Full Configuration Interaction Quantum Monte Carlo," Journal of Chemical Theory and Computation 15, no. 10 (2019), https://doi.org/10.1021/acs.jctc.9b00571
@article{osti_1720161,
author = {Petras, Hayley R. and Graham, Daniel S. and Ramadugu, Sai Kumar and Goodpaster, Jason D. and Shepherd, James J.},
title = {Fully Quantum Embedding with Density Functional Theory for Full Configuration Interaction Quantum Monte Carlo},
annote = {We here develop a fully quantum embedded version of initiator full configuration interaction quantum Monte Carlo (i–FCIQMC) and apply it to study an ionic bond (lithium hydride, LiH) and a covalent bond (hydrogen flouride, HF) physisorbed to a benzene molecule. The embedding is performed using a recently developed Huzinaga projection operator approach, which affords good synergy with i–FCIQMC by minimizing the number of orbitals in the calculation. When considering the dissociation energy of these bonds into closed-shell ionic fragments, we find that i–FCIQMC embedded in density functional theory (i–FCIQMC-in-DFT) delivers comparable accuracy with coupled cluster singles and doubles with perturbative triples embedded in density functional theory (CCSD(T)-in-DFT). In treating the bond dissociation energy curve of HF, i–FCIQMC-in-DFT has improved accuracy over CCSD(T)-in-DFT due to the presence of strong correlation. Lastly, we discuss the implications of the new i–FCIQMC-in-DFT method as applied to bond breaking in catalysis.},
doi = {10.1021/acs.jctc.9b00571},
url = {https://www.osti.gov/biblio/1720161},
journal = {Journal of Chemical Theory and Computation},
issn = {ISSN 1549-9618},
number = {10},
volume = {15},
place = {United States},
publisher = {American Chemical Society},
year = {2019},
month = {08}}