Bis[tris(1-methyl-1H-imidazol-2-yl)phosphine-kappa N-3(3)]iron(II) tetrachloroferrate(II) methanol tetrasolvate (ca 153 K) and bis[tris(1-methyl-1H-imidazol-2-yl)methanol-kappa N-3(3)]iron(III) bis[tetrachloroferrate(III)] chloride (redetermination, ca 153 K)

The first of the title compounds, [Fe(C 12H 15N 6P) 2][FeCl 4]-4CH 4O, is the first homoleptic bis(ligand)iron(II) species reported for this phosphorus bridgehead ligand; interestingly, the complex is isomorphous with its tris(1-methyl-1H- imidazol-2-yl)methanol counterpart, the second of the title compounds, [Fe(C 13H 16N 6O) 2][FeCl 4] 2Cl. In both compounds, the Fe atom of the cation lies on an inversion centre. The structure determinations presented here allow an interesting comparison of iron(II) and iron(III) species in similar coordination environments.