ABINITIO STUDY OF THE ELECTRONIC-STRUCTURE OF POLYMERIC QUASI-ONE-DIMENSIONAL SUPERLATTICES OF FURAN AND THIOPHENE

Ab initio band structure results of polyfuran (PFU) and polythiophene (PTP) obtained with a double zeta basis set are reported. The electronic density of states (DOS) of the various quasi-one-dimensional copolymers (superlattices) of the type (A(m)B(n))x (A = furan; B = thiophene) have been calculated numerically within the ab initio self-consistent field (SCF) tight binding approximation. These copolymers on the basis of the band positions of PFU and PTP are found to belong to the class of type I superlattices. The trends in their electronic structure and conduction properties as a function of (i) composition (m/n); (ii) block sizes m and n; and (iii) arrangement of the blocks in the copolymer chain are discussed.