Applying Electron Exchange Symmetry Properties to Better Understand Hund’s Rule

TCE

The Chemical Educator

ISSN: 1430-4171 (electronic version)

Table of Contents

Abstract Volume 13 Issue 3 (2008) pp 141-147

Applying Electron Exchange Symmetry Properties to Better Understand Hund’s Rule

Patrick E. Fleming

Department of Chemistry, San Jose State University, San Jose, CA 95192-0101, pfleming@sjsu.edu
Received July 2, 2006. Accepted December 23, 2006.

Published online: 1 June 2008

Abstract. A discussion of the shortcomings of Hund’s rule as presented in many current general chemistry textbooks is given. The ideas are developed through a presentation of concepts that are taught in upper-division courses on the same topic of the electronic structure of polyelectronic atoms. Electron exchange symmetry properties are used to demonstrate the need for producing symmetry-adapted linear combinations of both spin and orbital wavefunctions. The results of this analysis are interpreted using the Pauli exclusion principle. Finally, a modified statement of Hund’s rule is suggested that does not conflict with material covered later in the chemistry curriculum.

Key Words: In the Classroom; general chemistry; Hund's Rule

(*) Corresponding author. (E-mail: pfleming@sjsu.edu)

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