Thiophene-based material for non volatile organic memory devices: A combined experimental and theoretical study

A diphenyl bithiophene derivative (DPBT), which shows electrical bistability when tested in a two-terminal memory cell, has been extensively characterized with the aim to highlight the molecular root of the bistable behavior. A vibrational spectroscopic characterization has been carried out, supported by first-principles theoretical studies and X-ray analysis. Spectroscopic markers suitable to distinguish the different stable conformers of the molecule have been predicted and detected. These evidences have been further confirmed by the characterization of molecular species related to DPBT. The result obtained can be applied to determine the molecular isomers present in the organic active layer of the memory cell and opens the way to the identification of the molecular species involved in such electrical bistability.