Designing of novel donor-acceptor-donor framework based low band gap copolymers using an artificial intelligence approach

Donor-acceptor strategy is employed for designing low band gap hetero-aromatic copolymers using an artificial intelligence mechanism, viz., particle swarm optimization. The investigated structures include hetero-aromatic donor moieties, viz., pyrrole, thiophene and furan in combination with carbonyl and dicyanomethylene acceptor groups. The electronic properties of all the possible donor and acceptor combinations have been compared using the band structure results derived from ab initio Hartree Fock crystal orbital calculations. Of the studied copolymer combinations, the pyrrolecarbonyl donor-acceptor polymeric packaging is found to be most effective due to efficient push-pull effect in the polymer backbone. The pattern of optimized outcomes shows the significant influence of heteroatom on the electronic structures of the copolymers and provides judicious choice of donor and acceptor groups for molecular tailoring of low band gap materials.