In this study, we have calculated single-electron energy spectra via the Green's function based on the coupled-cluster singles and doubles (GFCCSD) method for isolated atoms from H to Ne. In order to check the accuracy of the GFCCSD method, we compared the results with the exact ones calculated from the full-configuration interaction. Consequently, we have found that the GFCCSD method reproduces not only the correct quasiparticle peaks but also satellite ones by comparing the exact spectra with the 6-31G basis set. It is also found that open-shell atoms such as C atom exhibit Mott gaps at the Fermi level, which the exact density-functional theory fails to describe. The GFCCSD successfully reproduces the Mott highest-occupied molecular orbital and lowest-unoccupied molecular orbital gaps even quantitatively. We also discussed the origin of satellite peaks as shake-up effects by checking the components of wave function of the satellite peaks. The GFCCSD is a novel cutting edge to investigate the electronic states in detail.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.5029536 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Triple Excitations in Green's Function Coupled Cluster Solver for Studies of Strongly Correlated Systems in the Framework of Self-Energy Embedding Theory.
J Phys Chem Lett
March 2023
Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States.
Embedding theories became important approaches used for accurate calculations of both molecules and solids. In these theories, a small chosen subset of orbitals is treated with an accurate method, called an impurity solver, capable of describing higher correlation effects. Ideally, such a chosen fragment should contain multiple orbitals responsible for the chemical and physical behavior of the compound.
View Article and Find Full Text PDFQuasiparticle energy spectra of isolated atoms from coupled-cluster singles and doubles (CCSD): Comparison with exact CI calculations.
J Chem Phys
July 2018
Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan.
In this study, we have calculated single-electron energy spectra via the Green's function based on the coupled-cluster singles and doubles (GFCCSD) method for isolated atoms from H to Ne. In order to check the accuracy of the GFCCSD method, we compared the results with the exact ones calculated from the full-configuration interaction. Consequently, we have found that the GFCCSD method reproduces not only the correct quasiparticle peaks but also satellite ones by comparing the exact spectra with the 6-31G basis set.
View Article and Find Full Text PDFGreen's Function Coupled-Cluster Approach: Simulating Photoelectron Spectra for Realistic Molecular Systems.
J Chem Theory Comput
August 2018
William R. Wiley Environmental Molecular Sciences Laboratory, Battelle, Pacific Northwest National Laboratory , K8-91, P.O. Box 999, Richland , Washington 99352 , United States.
In this paper, we present an efficient implementation for the analytical energy-dependent Green's function coupled-cluster with singles and doubles (GFCCSD) approach with our first practice being computing spectral functions of realistic molecular systems. Because of its algebraic structure, the presented method is highly scalable and is capable of computing spectral function for a given molecular system in any energy region. Several typical examples have been given to demonstrate its capability of computing spectral functions not only in the valence band but also in the core-level energy region.
View Article and Find Full Text PDFBand structures in coupled-cluster singles-and-doubles Green's function (GFCCSD).
J Chem Phys
May 2018
Department of Applied Physics, The University of Tokyo, Tokyo 113-8656, Japan.
Article Synopsis
- The GFCCSD method is a powerful technique for accurately determining electronic band structures and total energies in various systems, outperforming many other theoretical methods.
- Calculations of single-electron energy spectra for systems like the one-dimensional LiH, C, and Be chains show that the bandgap narrows due to correlation effects, and GFCCSD can capture both quasiparticle and satellite peaks in the band structures.
- The study demonstrates that by limiting the active space in calculations, significant computational savings can be achieved while still producing results that align closely with full-band calculations.
Coupled cluster Green function: Model involving single and double excitations.
J Chem Phys
April 2016
Cain Department of Chemical Engineering, Louisiana State University, Baton Rouge, Louisiana 70803, USA.
In this paper, we report on the development of a parallel implementation of the coupled-cluster (CC) Green function formulation (GFCC) employing single and double excitations in the cluster operator (GFCCSD). A key aspect of this work is the determination of the frequency dependent self-energy, Σ(ω). The detailed description of the underlying algorithm is provided, including approximations used that preserve the pole structure of the full GFCCSD method, thereby reducing the computational costs while maintaining an accurate character of methodology.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!