Calculated hyperpolarisabilities of polythiophenes, polyfurans and polypyrroles

Abstract

The calculated hyperpolarisabilities of substituted polythiophenes, polypyrroles and polyfurans containing an electron donor at one end of the molecule and an electron attractor at the other increase slowly with increasing number of heterocyclic rings. If the effective hyperpolarisability per unit volume is considered, the maximum values are obtained for the bifuran, the terpyrrole and the quaterthiophene. The largest hyperpolarisabilities are predicted for the polythiophenes, followed by the polypyrroles with the polyfurans showing the smallest values. Both the polythiophenes and polypyrroles have larger calculated hyperpolarisabilities than the similarly substituted polyphenyls but smaller than the corresponding polyenes.