Published online by Cambridge University Press: 01 December 2016
The influence of hydrostatic compression on the charge transport properties of an excellent 2,6-diphenylanthracene (2,6-DPA) semiconducting single crystal was investigated up to 10 GPa by performing density-functional calculations together with the tight binding approximation. In this pressure region the lattice constants a, b and c decrease by up to 0.948 Å (5.23%), 1.30 Å (17.26%), and 0.711 Å (11.34%), respectively, while the monoclinic angle β increases by 3.4°. The unit-cell volume decreases by increasing pressure, and the volume decreases by 30.5% at 10 GPa. In comparison, the C–C and C–H intermolecular distances within and between the herringbone layers reduced by 16–19% and 16–24%, respectively, in the same pressure ranges. The results indicate that under high pressure, the molecular planes of the crystal become more and more parallel to each other due to molecular rearrangement in the 2,6-DPA crystal. The band gap decreases with increasing pressure due to decreasing intermolecular separation between neighboring molecules. Finally, the results indicate an improvement of the hole mobility of 2,6-DPA single crystals under hydrostatic pressure.