Correlation energy functional in the density-matrix functional theory - art. no. 032517

Authors
Citation
K. Yasuda, Correlation energy functional in the density-matrix functional theory - art. no. 032517, PHYS REV A, 6303(3), 2001, pp. 2517
Citations number
43
Language
INGLESE
art.tipo
Article
Categorie Soggetti
Physics
Journal title
PHYSICAL REVIEW A
ISSN journal
1050-2947 → ACNP
Volume
6303
Issue
3
Year of publication
2001
Database
ISI
SICI code
1050-2947(200103)6303:3<2517:CEFITD>2.0.ZU;2-W
Abstract
A new systematic method is presented to construct a correlation energy func tional in the density-matrix functional theory. A new exact relation, parti cle-hole symmetry, is presented, which states that the exact functional giv es the same correlation energy for the first-order reduced density matrix ( 1-RDM) and the corresponding hole 1-RDM. Nakatsuji's density equations of t he first and the second orders together with the decoupling approximation o f the 3- and 4-RDMs are solved numerically to examine the properties of the correlation energy functional. This functional, defined as the solution of the set of equations, satisfies Levy's homogeneous coordinate scaling and the particle-hole symmetry and reproduces about 95% of the correlation ener gies of several molecules. By expanding these equations in perturbation ser ies the leading term of the correlation energy functional is identified. Nu merical analysis shows that this simplified functional, which contains one fitting parameter, reproduces the energies of several molecules accurately. The direction of further study is discussed.