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.