The effect of electron correlation on the topological and atomic properties of the electron density distributions of molecules

✍ Scribed by Russell J. Boyd; Liang-Chen Wang

• Publisher: John Wiley and Sons
• Year: 1989
• Tongue: English
• Weight: 780 KB
• Volume: 10
• Category: Article
• ISSN: 0192-8651
• DOI: 10.1002/jcc.540100310

✦ Synopsis

The topological properties of the electron density and the properties of a n atom in a molecule are calculated by means of second-order Mgller-Plesset perturbation theory (MP2) and compared with the results of configuration interaction calculations (CI2) which include all single and double substitutions from the Hartree-Fock reference configuration. A software package for analyzing the effects of electron correlation on the topological properties of the electron density of molecules is described. HzCO is used to provide a numerical example and to indicate that the number of bond critical points is unaffected by the inclusion of electron correlation. Correlation leads to only a small shift in the positions of bond critical points and a small change in the electron density a t bond critical points. It is further shown that the energy of an atom in a molecule can be calculated to an accuracy of 1 kcal/mol and the electron population of an atom to about 0.001e. A statistical method is used to show that the deviation of the MP2 correlation correction relative to the C12 correlation correction for a variety of atomic properties is about 25%.