Abstract:

Thieno-tetrathiafulvalene derivatives show great potential for use as organic field effect materials. We investigated the orbital energy levels, ionization potentials (IP), electron affinities (EA), and the reorganization energy (λ) of a series of fluoride substituted thieno-tetrathiafulvalene derivatives (c2FT, t2FT, and 4FT) using density functional theory at the B3LYP/6-31G(d,p) level. We, therefore, calculated the carrier mobilities of their dimers to investigate their charge transport properties. Furthermore, the effects of substituent position and the stacking mode on the charge transport characteristics were also discussed. Results show that the substituent position of fluorine atom slightly affects the mobility of the dithieno-tetrathiafulvalene derivatives, and that fluorination lowers their electron-donating abilities. These calculations are helpful for the design and synthesis of potentially photoelectric functional materials with high performance and stability.

Key words: Density functional theory, Organic field effect transistor, Tetrathiafulvalene derivatives, Reorganization energy, Mobility