Structure and characterization of charge transfer complexes of benzo[1,2-b:3,4-b′:5,6-b′′]trithiophene [C3h-BTT]

Abstract

Four charge-transfer complexes of C_3h-BTT (2) with the organic acceptors TCNQ, F₄TCNQ, chloranil, and fluoranil were prepared and crystallographically characterized. All four complexes form mixed stacks of donors and acceptors in a 1 : 1 or 2 : 1 stoichiometry. The degree of charge transfer in these complexes was estimated based on bond distances, infrared spectroscopy, and magnetic properties. Of the four complexes, C_3h-BTT·F₄TCNQ exhibited the highest ionicity with ρ = 0.27e. All four complexes were diamagnetic.