Studies of the correlation energy.

Title: Studies of the correlation energy.
Identifier: AAI9108107
identifier: 9108107
Creator: Gao, Xue-Qin.
Contributor: Adviser: Lou Massa
Date: 1990
Language: English
Publisher: City University of New York.
Subject: Chemistry, Physical
Abstract: Colle and Salvetti introduced a method to calculate the correlation energy Ec, based upon a correlated wavefunction which is obtained by multiplying a single determinant by a correlation factor.;In this thesis the Colle and Salvetti theoretical and numerical formulas are tested with He, Be, Ne and their isoelectronic series up to z = 36. We find the Colle-Salvetti formulas break down for ions with high value of Z.;We investigate a new formalism for calculating the correlation energy Ec. It is inspired by Colle and Salvetti's work, but differs in emphasizing the N-representability of the density matrix. The correlation factor is studied in a generalized form. This new formalism is tested with He and its isoelectronic ions. The calculations of Ec integrals employ our 3 dimensional Simpson integration program without any approximate series expansion. 70% of the exact correlation energies have been obtained using all terms of the usual Hamiltonian.;Further work to extend our method is suggested.
Type: dissertation
Source: PQT Legacy CUNY.xlsx
degree: Ph.D.