Simple Synthesis, Structural and Electronic Characterization of Soluble Contorted Pentacenes

Silylethynyl pentacenes have been a workhorse of small-molecule organic semiconductor research over the last two decades, but previous studies have identified dynamic disorder as a serious downfall for these materials. Thermal motion causing molecular vibrations results in fluctuation of the transfer integral between adjacent molecules and disrupts the charge transfer pathway through the bulk solid. In this work, we install phenyl damper groups onto the pentacene core of TIPS-pentacene to limit these vibrations, as observed by molecular dynamics simulations. Transistor devices show good hole mobilities and a consistent performance across a range of device dimensions. The damper groups also introduce a twist to the pentacene core, making these materials among a handful of contorted acene materials that still allow for π-stacking interactions applicable to electronics applications.