Estimation of the band structure of DNA on the basis of an ab initioSCF LCAO band structure of polycytosine

Abstract

A minimal basis set ab initio calculation has been performed for the four nucleotide bases and for the infinite polycytosine chain. The LEMO levels have been corrected using the ǑǍǑ procedure. Long-range correlation effects on the band structure of polyC have been computed using the electron polaron model. Using these calculated quantities and assuming that the other three homopolynucleotides have a similar band structure as polyC, the positions and widths of their valence and exciton bands have been approximated. Finally, by the superposition of the band structures of the homopolynucleotides the physically interesting bands of poly(G-C) and poly(A-T) have been estimated.