Bond Self-consistent Field VBSCF

The Valence Bond Self-Consistent Field (VBSCF) method has been devised by Balint-Kurti and van Lenthe (32), and was further modified by Verbeek (6,33) who also developed an efficient implementation in a package called TURTLE (11). Basically, the VBSCF method is a multiconfiguration SCF procedure that allows the use of nonorthogonal orbitals of any type. The wave function is given as a linear combination of VB structures, (Eq. 9.7). 

The flexibility of the valence bond self-consistent field (VBSCF) method can be exploited to calculate VB wave functions based on orbitals that are purely localized on a single atom or fragment. In such a case, the VBSCF wave function takes a classical VB form, which has the advantage of giving a very detailed description of an electronic system, as, for example, the interplay between the various covalent and ionic structures in a reaction. On the other hand, since covalent and ionic structures have to be explicitly considered for... 

VALENCE BOND SELF-CONSISTENT FIELD (VBSCF)... 

VBSCF Valence bond self-consistent field. A VB computational method. The VBSCF wave function is a linear combination of VB structures that simultaneously optimizes the structural coefficients and the orbitals of the structures. It can be used with any type of AOs OEOs, BDOs, and HAOs. With HAOs, we refer to the method as L-VBSCF L = localized. 

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