Inclusion of relativistic effects into ZDO methods. IV. Relativistic CNDO/1

✍ Scribed by Roman Boča

• Book ID: 104582780
• Publisher: John Wiley and Sons
• Year: 1990
• Tongue: English
• Weight: 471 KB
• Volume: 37
• Category: Article
• ISSN: 0020-7608
• DOI: 10.1002/qua.560370302

✦ Synopsis

Abstract

A relativistic, four‐component version of the CNDO (complete neglect of differential overlap) method is introduced. This method spans the class of zero‐differential‐overlap approximation and it utilizes a nonempirical parametrization based on results of atomic Dirac‐Fock calculations. The spin‐orbit splitting is included implicitly using the relativistic basis set which distinguishes Slater‐type functions of the lower and higher component spinors. The method is applicable to closed‐shell as well as to open‐shell systems. The actual version used is the R‐CNDO/1~χ~ with a variable scaling approach. Applications to molecular geometries, ionization potentials, and energies of spin‐orbit splitting are demonstrated for AH, AH~2~, AH~3~, MH, InX, and HgI~2~ molecules at the self‐consistent‐field level as well as in the second order of the many‐body perturbation theory.