X-ray correlated wavefunctions.
Item
-
Title
-
X-ray correlated wavefunctions.
-
Identifier
-
AAI9000694
-
identifier
-
9000694
-
Creator
-
Flocco, Maria M.
-
Contributor
-
Adviser: Lou Massa
-
Date
-
1989
-
Language
-
English
-
Publisher
-
City University of New York.
-
Subject
-
Chemistry, Physical
-
Abstract
-
First- and second order density matrices approximately N-representable by a correlated determinant wavefunction, whose reference state is a single determinant delivering the exact density, are derived. This density-matrix formalism is applied to the calculation of the correlation energy via a formula which includes both a kinetic energy contribution and a potential energy contribution. The single determinant of x-ray orbitals for the beryllium atom is used in a test calculation that yields 65 per cent of the correlation energy in a simple zeroth-order approximation. Extension of the calculations using a Hartree-Fock reference state is carried out for helium and beryllium atoms and for series of ions isoelectronic with them. For beryllium, the accuracy of the Hartree-Fock reference state results is comparable to the x-ray orbitals reference state case. The results for the series of ions are of poorer accuracy as the nuclear charge increases. Also, the empirical formula of Colle and Salvetti for the calculation of the correlation energy is applied to the series of ions isoelectronic with helium and beryllium. The accuracy of the results decreases with the increasing of the nuclear charge in both series.
-
Type
-
dissertation
-
Source
-
PQT Legacy CUNY.xlsx
-
degree
-
Ph.D.
