An ab initio self-consistent field (SCF) method with standard STO-3G and 6-31G* basis sets was used to study some normal saturated hydrocarbons. The occupied and virtual canonical orbitals were localized separately by Boys' procedure and the correlation energy corrections were calculated in the localized representation of the many-body perturbation theory. Introducing the concept of "neighbourhood order" the local and non-local effects can be separated and the correlation energy corrections can be partitioned accordingly. It was found that the correlation energy corrections in these molecules are predominantly of local origin. The contributions to the pair correlation energies are transferable to a good approximation. In analysing the contributions of the localized virtual orbitals, some interesting structural features were identified.
ASJC Scopus subject areas
- Condensed Matter Physics
- Physical and Theoretical Chemistry