Stochastic Resolution of Identity for Real-Time Second-Order Green’s Function: Ionization Potential and Quasi-Particle Spectrum

Autor:	Tyler Y. Takeshita, Roi Baer, Wenjie Dou, Eran Rabani, Ming Chen, Daniel Neuhauser
Rok vydání:	2019
Předmět:	GW approximation Physics 010304 chemical physics Perturbation (astronomy) Electron 01 natural sciences Spectral line Computer Science Applications Computational physics Ionization 0103 physical sciences Molecule Physical and Theoretical Chemistry Ionization energy Scaling
Zdroj:	Journal of Chemical Theory and Computation. 15:6703-6711
ISSN:	1549-9626 1549-9618
Popis:	We develop a stochastic resolution of identity approach to the real-time second-order Green's function (real-time sRI-GF2) theory, extending our recent work for imaginary-time Matsubara Green's function [ Takeshita et al. J. Chem. Phys. 2019 , 151 , 044114 ]. The approach provides a framework to obtain the quasi-particle spectra across a wide range of frequencies and predicts ionization potentials and electron affinities. To assess the accuracy of the real-time sRI-GF2, we study a series of molecules and compare our results to experiments as well as to a many-body perturbation approach based on the GW approximation, where we find that the real-time sRI-GF2 is as accurate as self-consistent GW. The stochastic formulation reduces the formal computatinal scaling from O(Ne5) down to O(Ne3) where Ne is the number of electrons. This is illustrated for a chain of hydrogen dimers, where we observe a slightly lower than cubic scaling for systems containing up to Ne ≈ 1000 electrons.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::4a5ac038d160724c3079bd85693473e5 https://doi.org/10.1021/acs.jctc.9b00918 Zobrazit plný text záznamu