Incremental Scheme for Local Correlation in Periodic Systems

In Sections 5.3 and 5.4 we consider Laplace-transform MP2 (LTMP2) and local MP2 (LMP2) methods extensions to periodic systems, implemented in computer codes GAUSSIAN03 [107] and CRYSCOR [117], respectively. These two extensions are similar to their molecular counterparts in the preliminary calculation of delocalized canonical orbitals (Bloch functions for periodic systems) and further construction of localized crystalline orbitals (Wannier functions for periodic systems). However the correlation effects for periodic systems may be taken into account in another way when the SCF calculations are made in Wannier-functions basis. Such an approach was named the incremental scheme [5,49,110] and is considered in the next section. [Pg.163]

Big Chemical Encyclopedia