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Title: Coupled cluster Green function: Model involving single and double excitations

Abstract

In this paper we report on the parallel implementation of the coupled-cluster (CC) Green function formulation (GF-CC) employing single and double excitations in the cluster operator (GF-CCSD). The detailed description of the underlying algorithm is provided, including the structure of ionization-potential- and electron-affinity-type intermediate tensors which enable to formulate GF-CC approach in a computationally feasible form. Several examples including calculations of ionization-potentials and electron a*ffinities for benchmark systems, which are juxtaposed against the experimental values, provide an illustration of the accuracies attainable in the GFCCSD simulations. We also discuss the structure of the CCSD self energies and discuss approximation that are geared to reduce the computational cost while maintaining the pole structure of the full GF-CCSD approach.

Authors:
; ;
Publication Date:
Research Org.:
Pacific Northwest National Laboratory (PNNL), Richland, WA (US), Environmental Molecular Sciences Laboratory (EMSL)
Sponsoring Org.:
USDOE
OSTI Identifier:
1337212
Report Number(s):
PNNL-SA-114925
Journal ID: ISSN 0021-9606; 48604; KP1704020
DOE Contract Number:
AC05-76RL01830
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 144; Journal Issue: 14
Country of Publication:
United States
Language:
English
Subject:
Coupled cluster Green function; excitations; computation; algorithm; Environmental Molecular Sciences Laboratory

Citation Formats

Bhaskaran-Nair, Kiran, Kowalski, Karol, and Shelton, William A. Coupled cluster Green function: Model involving single and double excitations. United States: N. p., 2016. Web. doi:10.1063/1.4944960.
Bhaskaran-Nair, Kiran, Kowalski, Karol, & Shelton, William A. Coupled cluster Green function: Model involving single and double excitations. United States. doi:10.1063/1.4944960.
Bhaskaran-Nair, Kiran, Kowalski, Karol, and Shelton, William A. Thu . "Coupled cluster Green function: Model involving single and double excitations". United States. doi:10.1063/1.4944960.
@article{osti_1337212,
title = {Coupled cluster Green function: Model involving single and double excitations},
author = {Bhaskaran-Nair, Kiran and Kowalski, Karol and Shelton, William A.},
abstractNote = {In this paper we report on the parallel implementation of the coupled-cluster (CC) Green function formulation (GF-CC) employing single and double excitations in the cluster operator (GF-CCSD). The detailed description of the underlying algorithm is provided, including the structure of ionization-potential- and electron-affinity-type intermediate tensors which enable to formulate GF-CC approach in a computationally feasible form. Several examples including calculations of ionization-potentials and electron a*ffinities for benchmark systems, which are juxtaposed against the experimental values, provide an illustration of the accuracies attainable in the GFCCSD simulations. We also discuss the structure of the CCSD self energies and discuss approximation that are geared to reduce the computational cost while maintaining the pole structure of the full GF-CCSD approach.},
doi = {10.1063/1.4944960},
journal = {Journal of Chemical Physics},
number = 14,
volume = 144,
place = {United States},
year = {Thu Apr 14 00:00:00 EDT 2016},
month = {Thu Apr 14 00:00:00 EDT 2016}
}
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