Configuration interaction, conjugated chains

Conjugated polymers have been studied theoretically since 1937. Quantum chemical calculations applied to conjugated chains include (i) Hiickel methods, for the rapid assessment of band structures " (ii) the Paiser-Parr-Pople configuration interaction method " (iii) complete neglect of differential overlap (CNDO) self-consistent field methods " (iv) ab initio Hartree-Fock calculations, which have given very close agreement with experimental results " " and (v) the valence effective Hamiltonian (VEH) method, which offers a considerable reduction in computational effort. ... 

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