Charge transfer salts of tetrathiafulvalene derivatives with magnetic iron(III) oxalate complexes: [TTF]7[Fe(ox)3]2·4H2O, [TTF]5[Fe2(ox)5]·2PhMe·2H2O and [TMTTF]4[Fe2(ox)5]· PhCN·4H2O (TMTTF = tetramethyltetrathiafulvalene) †

Three novel TTF (tetrathiafulvalene) and TMTTF (tetramethyltetrathiafulvalene) radical salts of monomeric and dimeric iron(III) oxalate magnetic complexes, [TTF]7[Fe(ox)3]2·4H2O 1, [TTF]5[Fe2(ox)5]·2PhMe·2H2O 2 and [TMTTF]4[Fe2(ox)5]·PhCN·4H2O 3, have been synthesized, and their structures and physical properties investigated. The structures for these semiconducting salts feature monodimensional stackings of the radical cations interleaved by the complexes [Fe(ox)3]3− and [Fe2(ox)5]4−, and solvent molecules. For the novel dinuclear complex [Fe2(ox)5]4− antiferromagnetic exchange between the two iron atoms through the oxalate bridge was found.