TY - JOUR
T1 - Linear-Response Time-Dependent Density Functional Theory with Stochastic Range-Separated Hybrids
AU - Zhang, Xu
AU - Lu, Gang
AU - Baer, Roi
AU - Rabani, Eran
AU - Neuhauser, Daniel
N1 - Publisher Copyright: Copyright © 2020 American Chemical Society.
PY - 2020/2/11
Y1 - 2020/2/11
N2 - Generalized Kohn-Sham density functional theory is a popular computational tool for the ground state of extended systems, particularly within range-separated hybrid (RSH) functionals that capture the long-range electronic interaction. Unfortunately, the heavy computational cost of the nonlocal exchange operator in RSH-DFT usually confines the approach to systems with at most a few hundred electrons. A significant reduction in the computational cost is achieved by representing the density matrix with stochastic orbitals and a stochastic decomposition of the Coulomb convolution (J. Phys. Chem. A 2016, 120, 3071). Here, we extend the stochastic RSH approach to excited states within the framework of linear-response generalized Kohn-Sham time-dependent density functional theory (GKS-TDDFT) based on the plane-wave basis. As a validation of the stochastic GKS-TDDFT method, the excitation energies of small molecules N2 and CO are calculated and compared to the deterministic results. The computational efficiency of the stochastic method is demonstrated with a two-dimensional MoS2 sheet (â¼1500 electrons), whose excitation energy, exciton charge density, and (excited state) geometric relaxation are determined in the absence and presence of a point defect.
AB - Generalized Kohn-Sham density functional theory is a popular computational tool for the ground state of extended systems, particularly within range-separated hybrid (RSH) functionals that capture the long-range electronic interaction. Unfortunately, the heavy computational cost of the nonlocal exchange operator in RSH-DFT usually confines the approach to systems with at most a few hundred electrons. A significant reduction in the computational cost is achieved by representing the density matrix with stochastic orbitals and a stochastic decomposition of the Coulomb convolution (J. Phys. Chem. A 2016, 120, 3071). Here, we extend the stochastic RSH approach to excited states within the framework of linear-response generalized Kohn-Sham time-dependent density functional theory (GKS-TDDFT) based on the plane-wave basis. As a validation of the stochastic GKS-TDDFT method, the excitation energies of small molecules N2 and CO are calculated and compared to the deterministic results. The computational efficiency of the stochastic method is demonstrated with a two-dimensional MoS2 sheet (â¼1500 electrons), whose excitation energy, exciton charge density, and (excited state) geometric relaxation are determined in the absence and presence of a point defect.
UR - http://www.scopus.com/inward/record.url?scp=85078734564&partnerID=8YFLogxK
U2 - https://doi.org/10.1021/acs.jctc.9b01121
DO - https://doi.org/10.1021/acs.jctc.9b01121
M3 - مقالة
C2 - 31899638
SN - 1549-9618
VL - 16
SP - 1064
EP - 1072
JO - Journal of Chemical Theory and Computation
JF - Journal of Chemical Theory and Computation
IS - 2
ER -