An Ab Initio Structural Analysis of Polythiophene Oligomers

Abstract

Detailed ab initio quantum mechanical calculations of a number of polythiophene oligomers are carried out to ascertain relative stability of structures bonding through a and B carbons. Energetics of dimers, trinerstetramers, and pentamers with all possible linkages types are obtained from fully optimized geometries. This determines the relative energy of a and β carbons lingkages  of the oligomers Final energy of the oligoners is calculated using different ab-initio basis sets (3-21G and STO-3G) of the polythiophene geometry. Geometrical  structures and energetics of thiophene oligomers are presented.