Polythiophene as a sensor model for chlorofluorocarbon, fluorine, and oxygen gas using DFT calculations.

Adsorption of CCl3F, CCl2F2, CClF3, F2, and O2 has been investigated systematically on the polythiophene (PT) moieties using density functional theory (DFT) calculations at the B3LYP/6-31G (d) level. Here, geometry optimizations have been performed on some polythiophene (5PT and 7PT) complexes. Likewise, adsorption energies, dipole moments, HOMO-LUMO orbital analysis, density of states (DOSs), global indices, and UV-vis spectra are calculated using the DFT method. Energies of interaction and HOMO-LUMO gap show that polythiophene has the highest sensitivity toward O2 for B3LYP functional. According to our findings, CFCs, F2, and O2 molecules can be physically adsorbed on the moieties of polythiophene.