An Organic Metal Derived from a Selenium Analogue of Benzothienobenzothiophene

Abstract

AbstractBenzothieno[3,2‐b]benzothiophene (BTBT) is an excellent organic transistor material, and its charge‐transfer salt (BTBT)2PF6 is an organic metal that exhibits conductivity as high as 1500 S cm–1 at room temperature. Here, we report a charge‐transfer salt of the selenium analogue, benzoseleno[3,2‐b]benzoselenophene (BSBS). (BSBS)2TaF6 is a one‐dimensional metal isostructural to (BTBT)2PF6. The resistance jump temperature is reduced from 150 to 90 K, and the increase of the low‐temperature resistivity is largely diminished. However, the spin susceptibility shows an obvious drop below 50 K, which implies that the low‐temperature ground state is essentially a singlet state.