Abstract
Charge transfer salts with stoichiometry β″-(BEDT-TTF) [M(CO),](18-crown-6 ether)(9HO), where M= Cr, Ga or Fe and x= 2 or 3 are reported. Their structures suggest that proton migration is possible. Variable temperature resistivity measurements on the Cr salt show metallic behaviour down to 180K. Magnetic susceptibility of the Cr salt is paramagnetic down to 1.8 K. Preliminary impedance measurements suggest that the proton conductivities of the Cr and Ga salts are the order of 10 S cm at 300 K. © 2003 Elsevier Science B.V. All rights reserved.