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Exploring, designing, and synthesizing novel organic field-effect transistor(OFET) materials have kept an important and hot issue in organic electronics. In the current work, the charge transport properties for 2,5-di(cyanovinyl)thiophene/furan crystal associating two pentafluorophenyl units linked via the azomethine bond, CTE and CFE have been theoretically investigated by means of density functional theory(DFT) calculations coupled with the incoherent charge-hopping mechanism and the kinetic Monte Carlo simulation. Results show that these two compounds possess remarkably low-lying HOMO(–7.0 eV) and LUMO(–4.0 e V) levels, as well as large electron affinities(> 3.0 e V), which indicate their high stability exposed to air as promising OFET materials. However, the μh value at room temperature(T = 300 K) is predicted to be 2.058×10~(-7) cm~2·V~(-1)·s~(-1), and the μe is as low as 9.834×10~(-8) cm~2·V~(-1)·s~(-1) for CFT crystal. Meanwhile, these two values are 7.561 × 10~(-8) and 8.437 × 10~(-8) cm~2·V~(-1)·s~(-1) for the CFE crystal, respectively. Furthermore, the simulation of angle-dependent mobility in the a-b, a-c, and b-c crystal planes shows that the charge transport in CTE and CFE crystals is remarkably anisotropic, which maybe is helpful for the fabrication of high-performance OFET devices.
Exploring, designing, and synthesizing novel organic field-effect transistor (OFET) materials have kept an important and hot issue in organic electronics. In the current work, the charge transport properties for 2,5-di (cyanovinyl) thiophene / furan crystal associating two pentafluorophenyl units linked via the azomethine bond, CTE and CFE have been theoretically investigated by means of density functional theory (DFT) calculations coupled with the incoherent charge-hopping mechanism and the kinetic Monte Carlo simulation. Results show that these two compounds have remarkably low -lying HOMO (-7.0 eV) and LUMO (-4.0 eV) levels, as well as large electron affinities (> 3.0 eV), which indicates their high stability exposed to air as promising OFET materials. However, the μh value at The room temperature (T = 300 K) is predicted to be 2.058 × 10 -7 cm -2 · V -1 · s -1, and the μe is as low as 9.834 × 10 -6 -8) cm ~ 2 · V -1 · s ~ (-1) for CFT crystal. Meanwhile, these two values are 7.561 × 10 ~ (-8) and 8.437 × 10 -8 cm -2 · V -1 · s -1 for the CFE crystal, respectively. Furthermore, the simulation of angle-dependent mobility in the ab, ac, and bc crystal planes shows that the charge transport in CTE and CFE crystals is remarkably anisotropic, which maybe helpful for the fabrication of high-performance OFET devices.