A series of complexes of the phosphorus-based TTF ligand o-P2 with the metal ions Fe(II), Co(II), Ni(II), Pd(II), Pt(II), and Ag(I)
Résumé
Reactions of 3,4-dimethyl-3 ,4-bis(diphenylphosphino)tetrathiafulvalene, o-P2, with [BF 4 ] − salts of Fe(II), Co(II), Ni(II), Pd(II), and Pt(II) yield complexes of general formula [M(o-P2) 2 ][BF 4 ] 2. Similar reactions between o-P2 and AgSbF 6 or AgPF 6 produced the salts [Ag(o-P2) 2 ][X] where X = [SbF 6 ] − or [PF 6 ] −. The resulting compounds were fully characterized by 1 H and 31 P{ 1 H} NMR, infrared and electronic absorption spectroscopies, cyclic voltammetry, FAB-MS and single-crystal X-ray diffraction. The paramagnetic Co(II) compound exhibits an S = 3/2 state with large spin–orbit coupling contribution at higher temperatures and an effective S = 1/2 state below 20 K. Electrochemical studies of the compounds indicate that the two functionalized TTF ligands are not in electronic communication and that they essentially behave as isolated redox centers.