Pople-Segal-Santry self-consistent

Probably the most significant orbital calculations at the present time are those which were made by the Pople-Segal-Santry self-consistent molecular-orbital method using the complete set of 5s-, 5p-, and 5t -orbitals of tin [28]. The occupancies of the 5s-, 5p-, and 5 /-orbitals were obtained, and the 5s-electron density at the nucleus calculated from the Fermi-Segre equation (using a modified form of Burn s screening rules) for the assumed tetrahedral... 

J. A. Pople, D. P. Santry, and G. A. Segal, Approximate self-consistent molecular orbital... 

Klopman (1964) has formulated a self-consistent semiempirical formulation. Other formalisms have been given by Pople, Santry, and Segal (1965) and Kaufman (1965). Katagiri and Sandorfy (1966) have presented also a similar formulation, with particular emphasis on the evaluation of integrals and the interpretation of ionization potentials and electronic spectra of saturated hydrocarbons. 

Pople, J.A., Santry, D.P., and Segal, G.A., Approximate self-consistent molecular orbital theory. I. Invariant procedures, J. Chem. Phys., 43, S129-S135 (1965). 

Pople J A, D P Santry and G A Segal 1965. Approximate Self-Consistent Molecular Orbital Theory. 1. 

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