Perpendicular crossing chains enable high mobility in a noncrystalline conjugated polymer
Jack F. Coker, Stefania Moro, Anders S. Gertsen, Xingyuan Shi, Drew Pearce, Martin P. van der Schelling, Yucheng Xu, Weimin Zhang, Jens Wenzel Andreasen, Chad R. Snyder, Lee J. Richter, Matthew J. Bird, Iain McCulloch, Giovanni Costantini, Jarvist M. Frost, Jenny Nelson
Abstract
The nature of interchain π-system contacts, and their relationship to hole transport, are elucidated for the high-mobility, noncrystalline conjugated polymer C16-IDTBT by the application of scanning tunneling microscopy, molecular dynamics, and quantum chemical calculations. The microstructure is shown to favor an unusual packing motif in which paired chains cross-over one another at near-perpendicular angles. By linking to mesoscale microstructural features, revealed by coarse-grained molecular dynamics and previous studies, and performing simulations of charge transport, it is demonstrated that the high mobility of C16-IDTBT can be explained by the promotion of a highly interconnected transport network, stemming from the adoption of perpendicular contacts at the nanoscale, in combination with fast intrachain transport.