We generalize antisymmetric geminal products to more than just one generating geminal using an Aufbau Ansatz similar to the Hartree-Fock theory. Investigation of Li-, Be, B+, LiH, BeH+, and He2 shows a very high recovery of electron-correlation energy using this Aufbau Ansatz. The method is inherently multideterminantal and insensitive to symmetry problems. The computational complexity is en par with configuration interaction of singles and doubles.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1063/1.2133732 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Initial Maximum Overlap Method for Large Systems by the Quantum Mechanics/Extremely Localized Molecular Orbital Embedding Technique.
J Chem Theory Comput
July 2021
Université de Lorraine & CNRS, Laboratoire de Physique et Chimie Théoriques (LPCT), UMR CNRS 7019, 1 Boulevard Arago, F-57078 Metz, France.
Quantum chemistry offers a large variety of methods to treat excited states. Many of them are based on a multireference wave function ansatz and are therefore characterized by an intrinsic complexity and high computational costs. To overcome these drawbacks and also some limitations of simpler single-reference approaches (e.
View Article and Find Full Text PDFTransition density matrices of Richardson-Gaudin states.
J Chem Phys
March 2021
Département de Chimie, Université Laval, Québec, Québec G1V 0A6, Canada.
Recently, ground state eigenvectors of the reduced Bardeen-Cooper-Schrieffer (BCS) Hamiltonian, Richardson-Gaudin (RG) states, have been employed as a wavefunction ansatz for strong correlation. This wavefunction physically represents a mean-field of pairs of electrons (geminals) with a constant pairing strength. To move beyond the mean-field, one must develop the wavefunction on the basis of all the RG states.
View Article and Find Full Text PDFExcited states via coupled cluster theory without equation-of-motion methods: Seeking higher roots with application to doubly excited states and double core hole states.
J Chem Phys
December 2019
Department of Chemistry, University of California, Berkeley, California 94720, USA and Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
In this work, we revisited the idea of using the coupled-cluster (CC) ground state formalism to target excited states. Our main focus was targeting doubly excited states and double core hole states. Typical equation-of-motion (EOM) approaches for obtaining these states struggle without higher-order excitations than doubles.
View Article and Find Full Text PDFFarewell to Diversity? New State Zones of Health Care Service in China's Far West.
J Entwickl Polit
March 2012
Department for East Asian Studies, University of Vienna
Using James Scott's (2009) theoretical framework of the interaction between the state and peripheral people, we argue that the welfare state should be regarded as a in the context of the state's endeavours to project its power to distant peoples in assigned state zones. Our discussion is based on interviews in Xinyuan County in the Western part of the Xinjiang Uyghur Autonomous Region, China. Presenting current policies and alternative policy options discussed at the local level for providing primary health care in rural China, we argue that decisions made in the implementation process did not respond to the special health needs of mobile pastoralists in the high plains, but were part of the central state logic of homogenising settlement efforts and health care.
View Article and Find Full Text PDF[Organization of data and tissue banks for new prognostic factors in adenocarcinoma of the prostate. An interdisciplinary uropathologic approach].
Urologe A
September 2007
Klinik für Urologie der Universität Regensburg am Caritas-Krankenhaus St. Josef, Landshuterstrasse 65, 93053 Regensburg.
Want 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!