Structure-Property Relationships in Thienoacenes for Improved Transport Properties

In spite of tremendous progress in molecular design, engineering and processing, only few small molecule organic semiconductors (OSCs) have reached charge carrier mobilities (µ) higher than 10 cm²/Vs, typically with single-crystal devices. However, µ is a material property and not a molecular one. It is thus of paramount importance to take supramolecular order into consideration at all length scales. As recently evidenced, the best OSCs tend to self-organize into large plate-like single-crystals exhibiting a layer-by-layer herringbone packing motif.¹ Moreover, thermal lattice fluctuations cause temporal variations of transfer integrals (J) and impose a transient localization of charges leading to reduced macroscopic µ in these weakly bonded van der Waals solids.² We will present recent progress achieved in our group in terms of molecular design and understanding of the impact of thermal energetic disorder: design by theory, crystal engineering, quantum-chemical calculations and evaluation of transport properties in electronic devices.<br/><br/><br/><u>References:</u><br/>1. Schweicher, <i>Adv. Mater.</i> <b>2020</b>, 32, 10, 1905909; Fratini, <i>Nature Materials</i> <b>2020</b>, 19, 491<br/>2. Fratini, <i>Adv. Funct. Mater.</i> <b>2016</b>, 26, 2292; Fratini, <i>Nature Materials</i> <b>2017</b>, 16, 998; Schweicher, <i>Adv. Mater.</i> <b>2019</b>, 31, 43, 1902407; Banks, <i>Adv. Funct. Mater.</i> <b>2023</b>, 33, 38, 2303701; Giannini, <i>Acc. Chem. Res.</i> <b>2022</b>, 55, 6, 819; Giannini, Di Virgilio, <i>Nature Materials</i> <b>2023</b>, 10.1038/s41563-023-01664-4