THE CR-2 POTENTIAL-ENERGY CURVE STUDIED WITH MULTICONFIGURATIONAL 2ND-ORDER PERTURBATION-THEORY

被引：123

作者：

ANDERSSON, K

ROOS, BO

MALMQVIST, PA

WIDMARK, PO

机构：

[1] Department of Theoretical Chemistry, Chemical Centre, University of Lund, S-221 00 Lund

来源：

CHEMICAL PHYSICS LETTERS | 1994年 / 230卷 / 4-5期

关键词：

D O I：

10.1016/0009-2614(94)01183-4

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

The potential energy curve of the Cr-2 ground state has been obtained by multiconfigurational second-order perturbation theory. In this study 6-8 singularities appear in the potential curve for bond distances ranging from 1.5 to 2.2 Angstrom. However, these singularities are weak enough to allow the determination of approximate spectroscopic constants. By employing a large atomic natural orbital (ANO) basis set of the size 8s7p6d4f and by including 3s, 3p correlation effects and relativistic corrections, the following values were obtained (experimental data within parentheses): equilibrium bond length r(e)=1.71 Angstrom ( 1.68 Angstrom), harmonic vibrational frequency omega(e)=625 cm(-1) (481 cm(-1)) and dissociation energy D-0=1.54 eV (1.44+/-.0.06 eV).

引用

页码：391 / 397

页数：7

共 20 条

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