Tetrathia[22]annulene[2,1,2,1]: physical properties, crystal structure and application in organic field-effect transistors

Abstract

The optical, electrochemical, electrical and thermal properties of tetrathia[22]annulene[2,1,2,1]1 were studied in detail. Good thermal stability was observed by thermogravimetric analysis. The molecule was almost coplanar and packed into a sandwich–herringbone arrangement in the single crystal as revealed by single crystal X-ray analysis. Compound 1 was successfully used as a p-type semiconductor in OFETs and the performance of the devices displayed good reproducibility at ambient conditions. When the devices of 1 were fabricated on OTS-treated SiO₂/Si substrates at room temperature, the best performance was measured, with a hole mobility of up to 0.05 cm² V^–1 s^–1 and an on/off ratio above 10³. This good performance resulted from the well-ordered molecular packing as revealed by XRD and AFM analysis.