Thiophene-Furan oligomers: Beyond-DFT Study of Electronic and Optical Properties

Abstract Thiophene oligomers are an important class of organic materials for photovoltaic applications, owing to their unique optoelectronic properties. Recently it has been suggested that incorporation furan units the thiophene chains, maintaining chain structure, namely thienylfuran linear oligomers, can bring improvements final material. In this work, we present a theoretical study thiophene, and short up 4 units. Structural electronic properties were obtained using Hartree-Fock (HF) Density Functional Theory (DFT) calculations plus beyond mean-field methodologies, specifically Second-order Möller-Plesset perturbation theory on HF (HF-MP2) many-body by G0W0 approximation DFT (G0W0@DFT). The optical calculated top G0W0@DFT data Bethe-Salpeter Equation. We investigate from monomers T F tetramers with different sequencing TT, TF or FF, always bonded through usual carbon atoms. As well known uniform oligothiophene also here any TT find torsion angle 150° while all other result planar, which be relevant film producing. Also first transitions reaches promising threshold ∽ 3 eV at tetramer length, combined ionization potentials around ∼ 6.5 − 7 compatible semiconductor/substrate band alignments, confirms relevance these compounds applications.