Synthesis and charge-transfer complexes of a new donor molecule, TP-EDOT

Abstract

A new donor molecule, TP-EDOT, was synthesized having a sulfur atom at the terminal position with a significant atomic orbital coefficient in the HOMO. Despite the instability of TP-EDOT to acids, crystalline complexes have been obtained with inorganic anions. The 2 ∶ 1 complex with PF₆⁻ was a Mott insulator, in which the localized spins exhibited a two-dimensional antiferromagnetic behaviour based on a novel three-dimensional spin arrangement. The semiconducting (TP-EDOT)₃Sb₂F₁₁(benzene) complex showed a low-lying energy electronic transition at around 5000 cm⁻¹, which indicated the partial charge-transferred or charge disproportioned ground state. Although the trimer of donor molecules, which accommodated one charge carrier, formed uniform stack along the c-axis, this complex showed diamagnetic nature.