Applications of a simple molecular wavefunction. Part 11.—Extension of FSGO method to open-shell treatments
Abstract
The FSGO method which, in its simple form, assigns electrons in pairs to orbitals represented by single Gaussian functions, is extended here in two ways: (1) to an open-shell treatment in which a single determinant is used; (2) to an open-shell treatment in which several determinants are used so that the wave function is an eigenfunction of the S2 operator. Formulae are given.