Characterization and spectral properties of the new organic metal (BEDT-TTF)6(Mo8O26)(DMF)3

A new charge transfer salt based on bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and the [Mo8O26](4-) anion was synthesized and characterized by X-ray and spectral analysis. The crystals are triclinic, space group P (1) over bar, a = 12.996(3) Angstrom, b = 13.135(3) Angstrom, c = 20.705(5) Angstrom, alpha=72.01(2)degrees, beta=85.94(2)degrees, gamma=60.02(2)degrees, V=2896.9 Angstrom(3), Z=1. The structure consists of alternating organic and inorganic layers. The inorganic layers are formed by [Mo8O26](4-) anions and dimethyl formamide (DMF) molecules. The organic layers are built of two different types of BEDT-TTF molecules bonded by short S... S contacts. The compound is a metal with sigma approximate to 3 S cm(-1) at room temperature. IR and Raman spectra of single crystals were analyzed and an assignment of the vibrational features was proposed. The temperature dependencies of transport parameters were obtained using the Drude-Lorentz model. (C) 2002 Elsevier Science B.V. All rights reserved.