On the Structure and Properties of TMTTF and TMTSF Salts: Experimental Evidence for the Importance of Interchain Couplings

The structure and physical properties of tetramethyl-tetrathiofulvalène (TMTTF) salts are reviewed. New results are given about (TMTTF)2 PF6, (TMTTF)2 ClO4 and the selenium analog (TMTSF)2 ClO4. An experimental relationship is shown between the electrical and magnetic properties and the closest contacts S-S or Se-Se of neighbouring stacks.