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Title: Multireference linearized coupled cluster theory for strongly correlated systems using matrix product states

Abstract

We propose a multireference linearized coupled cluster theory using matrix product states (MPSs-LCC) which provides remarkably accurate ground-state energies, at a computational cost that has the same scaling as multireference configuration interaction singles and doubles, for a wide variety of electronic Hamiltonians. These range from first-row dimers at equilibrium and stretched geometries to highly multireference systems such as the chromium dimer and lattice models such as periodic two-dimensional 1-band and 3-band Hubbard models. The MPS-LCC theory shows a speed up of several orders of magnitude over the usual Density Matrix Renormalization Group (DMRG) algorithm while delivering energies in excellent agreement with converged DMRG calculations. Also, in all the benchmark calculations presented here, MPS-LCC outperformed the commonly used multi-reference quantum chemistry methods in some cases giving energies in excess of an order of magnitude more accurate. As a size-extensive method that can treat large active spaces, MPS-LCC opens up the use of multireference quantum chemical techniques in strongly correlated ab initio Hamiltonians, including two- and three-dimensional solids.

Authors:
 [1];  [1];  [2]
  1. Max Planck Institute for Solid State Research, Heisenbergstraße 1, 70569 Stuttgart (Germany)
  2. (United Kingdom)
Publication Date:
OSTI Identifier:
22489554
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 143; Journal Issue: 10; Other Information: (c) 2015 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ALGORITHMS; CHROMIUM; CONFIGURATION INTERACTION; DENSITY MATRIX; GROUND STATES; HAMILTONIANS; HUBBARD MODEL; SOLIDS

Citation Formats

Sharma, Sandeep, E-mail: sanshar@gmail.com, Alavi, Ali, E-mail: a.alavi@fkf.mpg.de, and Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW. Multireference linearized coupled cluster theory for strongly correlated systems using matrix product states. United States: N. p., 2015. Web. doi:10.1063/1.4928643.
Sharma, Sandeep, E-mail: sanshar@gmail.com, Alavi, Ali, E-mail: a.alavi@fkf.mpg.de, & Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW. Multireference linearized coupled cluster theory for strongly correlated systems using matrix product states. United States. doi:10.1063/1.4928643.
Sharma, Sandeep, E-mail: sanshar@gmail.com, Alavi, Ali, E-mail: a.alavi@fkf.mpg.de, and Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW. 2015. "Multireference linearized coupled cluster theory for strongly correlated systems using matrix product states". United States. doi:10.1063/1.4928643.
@article{osti_22489554,
title = {Multireference linearized coupled cluster theory for strongly correlated systems using matrix product states},
author = {Sharma, Sandeep, E-mail: sanshar@gmail.com and Alavi, Ali, E-mail: a.alavi@fkf.mpg.de and Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW},
abstractNote = {We propose a multireference linearized coupled cluster theory using matrix product states (MPSs-LCC) which provides remarkably accurate ground-state energies, at a computational cost that has the same scaling as multireference configuration interaction singles and doubles, for a wide variety of electronic Hamiltonians. These range from first-row dimers at equilibrium and stretched geometries to highly multireference systems such as the chromium dimer and lattice models such as periodic two-dimensional 1-band and 3-band Hubbard models. The MPS-LCC theory shows a speed up of several orders of magnitude over the usual Density Matrix Renormalization Group (DMRG) algorithm while delivering energies in excellent agreement with converged DMRG calculations. Also, in all the benchmark calculations presented here, MPS-LCC outperformed the commonly used multi-reference quantum chemistry methods in some cases giving energies in excess of an order of magnitude more accurate. As a size-extensive method that can treat large active spaces, MPS-LCC opens up the use of multireference quantum chemical techniques in strongly correlated ab initio Hamiltonians, including two- and three-dimensional solids.},
doi = {10.1063/1.4928643},
journal = {Journal of Chemical Physics},
number = 10,
volume = 143,
place = {United States},
year = 2015,
month = 9
}
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