Reviving BVDT-TTF and EVT-TTF salts

Abstract

Herein are reported the synthesis, in-depth structural description and conducting properties of various salts of the symmetric bis-vinylenedithio-tetrathiafulvalene (BVDT-TTF) and dissymmetric ethylene-vinylenedithio-tetrathiafulvalene (EVT-TTF). Compared to the omnipresent bis-ethylenedithio-tetrathiafulvalene (BEDT-TTF) these two closely related and easily synthesizable organic donors have been reported ca. 200 times less in the literature. Four new structures of organic conductors are herein investigated and analysed through a battery of techniques, including X-ray analysis on single-crystals, conductivity measurements, Raman spectroscopy and band structure calculations. All materials exhibit semiconducting behaviours with conductivities in the 10⁻³ to 10⁻¹ S cm⁻¹ range at RT and ambient pressure. The impact of the structural or electronic disorder on the conductivity and dimensionality of the salts is examined.