Applications of CASSCF

Abstract

Multiconfigurational wave functions are necessary in a number of applications such as breaking of bonds and curve crossing problems. One of the most important multiconfigurational methods is CASSCF. Three applications are discussed here: cis-trans isomerization, as a reasonably simple curve crossing problem. Curve crossing connected to electron-transfer contains the additional problem that the electronic interaction |D| may tend to zero. The electron pair transfer problem includes multiconfigurational wave functions and requires a very accurate calculation of the interaction between two configurations, the charged and spin-coupled configurations.