Orbital Configuration: Terms, States, and Configuration State Functions

• Published in: Journal of chemical education Vol. 95; no. 9; pp. 1592 - 1600
• Main Author: Brom, Joseph M
• Format: Journal Article
• Language: English
• Published: Easton American Chemical Society and Division of Chemical Education, Inc 11-09-2018; Division of Chemical Education, Inc; American Chemical Society
• Subjects: Chemistry; Classification; Configurations; Correlation; Decision Making; Electron states; Ethylene; Geometry; Graduate Students; Group theory; Molecular orbitals; Molecular Structure; Problem Solving; Science Instruction; Symmetry; Teaching Methods; Undergraduate Students; Vocabulary; Wave functions; Graduate Education/Research; Upper-Division Undergraduate; Quantum Chemistry; Problem Solving/Decision Making; Physical Chemistry; Group Theory/Symmetry
• ISSN: 0021-9584; 1938-1328
• DOI: 10.1021/acs.jchemed.8b00187

Molecular orbital configurations give rise to electronic terms comprising corresponding electronic states. Electronic terms possess symmetry classifications, which are denoted by a term symbol, based on the symmetry properties of the electronic wave functions associated with the states. Using the methylene radical, and both planar and twisted ethylene molecules as examples, the symmetry classifications of the wave functions connected to orbital configurations are determined. The wave functions associated with the open-shell ···(2e)2 ground configuration of twisted, D 2d ethylene present an informative example of how to use group theory to determine the configuration state functions associated with the six states arising from this configuration.