High mobility has always been an important metric in
the study
of organic semiconductor materials (OSCs). Various external factors,
including pressure, temperature, and light, have the potential to
influence the mobility of OSCs. Pressure, in particular, can modify
the intermolecular distance and molecular orbital, making it an ideal
candidate for controlling carrier mobility and optimizing semiconductor
device performance. However, the effect of pressure on the photoelectric
behavior of organic molecules with different stacking patterns remains
uncertain. To address this, we prepared a series of anthracene-based
semiconductor molecules to predict the effect of hydrostatic pressure
on the charge-transport properties through first-principles and multiscale
computational simulations based on hopping and band transport mechanisms.
Our findings indicate that the mobility of TIPSAntNa in one-dimensional
(1D) π-stacking is not consistently monotonic but rather reaches
a peak at 5 GPa, which is attributed to the gradual increase in pressure-induced
reorganization energy (λ) and the periodic variation in transfer
integral (V). Differently, for herringbone stacked crystals, the Vs
increase with higher pressure, resulting in higher mobility under
such conditions. This means that 1D π-stacked organic molecules
exhibit enhanced sensitivity to pressure, resulting in higher mobility
at low pressures. Additionally, it is noteworthy that the appropriate
pressure control can convert a p-type transport material into an n-type
transport material. Consequently, our research provides valuable insights
for achieving enhanced performance of OSCs by modulating pressure.