General Considerations for Many Electron Systems
Thus far our considerations have in general been limited to systems containing only a single electron. While we have seen that many important principles and techniques can be developed using those cases, we shall now see that a major new concept is needed for systems containing more than one electron. That concept (the Pauli Exclusion Principle) will be developed in the sections to follow, along with a number of analyses and techniques that are of substantial importance in contemporary applications of quantum mechanics to chemistry. Before doing that, however, it is useful to introduce several conceptual approaches to many electron systems that were developed early, as well as the basic concepts of group theory. These will help us to understand and motivate the discussions to follow, as well as to provide useful tools for incorporating and understanding symmetry properties of molecules and wavefunctions.
KeywordsIrreducible Representation General Consideration Symmetry Operation Virial Theorem Character Table
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