Effective density terms in proper integral equations

Kippi M. Dyer, John S. Perkyns, Bernard Pettitt

Research output: Contribution to journalArticle

9 Citations (Scopus)

Abstract

Two complementary routes to a new integral equation theory for site-site molecular fluids are presented. First, a simple approximation to a subset of the atomic site bridge functions in the diagrammatically proper integral equation theory is presented. This in turn leads to a form analogous to the reactive fluid theory, in which the normalization of the intramolecular distribution function and the value of the off-diagonal elements in the density matrix of the proper integral equations are the means of propagating the bridge function approximation. Second, a derivation from a topological expansion of a model for the single-site activity followed by a topological reduction and low-order truncation is given. This leads to an approximate numerical value for the new density coefficient. The resulting equations give a substantial improvement over the standard construction as shown with a series of simple diatomic model calculations.

Original languageEnglish (US)
Article number204512
JournalJournal of Chemical Physics
Volume123
Issue number20
DOIs
StatePublished - 2005
Externally publishedYes

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Integral equations
integral equations
approximation
Fluids
fluids
Set theory
set theory
Distribution functions
derivation
distribution functions
routes
expansion
coefficients

ASJC Scopus subject areas

  • Atomic and Molecular Physics, and Optics

Cite this

Effective density terms in proper integral equations. / Dyer, Kippi M.; Perkyns, John S.; Pettitt, Bernard.

In: Journal of Chemical Physics, Vol. 123, No. 20, 204512, 2005.

Research output: Contribution to journalArticle

Dyer, Kippi M. ; Perkyns, John S. ; Pettitt, Bernard. / Effective density terms in proper integral equations. In: Journal of Chemical Physics. 2005 ; Vol. 123, No. 20.
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