The structure consists of two-dimensional sheets of BEDT-TTF [BEDT-TTF, or ET = 3,4;3',4'-bis(ethylene-dithio)-2,2',5,5'-tetrathiafulvalene] separated by PF6-along the crystallographic b axis. Intermolecular S-S distances shorter than the sum of the van der Waals radii (3.6 angstrom) are found between both interstack and intrastack BEDT-TTF molecules.