trans-Dichlorido­tetra­kis­[(di­methyl­phosphor­yl)methanaminium-κO]cobalt(II) tetra­chloridocobaltate(II)

The asymmetric unit of the title structure, [CoCl2(C3H11NOP)4][CoCl4]2, consists of one half of the trans-dichlorido-tetra-kis-[(di-methyl-phosphor-yl)methanaminium]cobalt(II) tetra-cation lying on an inversion center and one tetra-chloridocobaltate(II) dianion on a general position. Four O-coordinated cationic (di-methyl-phosphor-yl)methanaminium (dpmaH(+)) ligands occupy the equatorial coordination sites, whereas the chloride ligands occupy axial positions of the roughly o-cta-hedral coordination polyhedron of the cobalt metal center. Intra-molecular hydrogen bonds between the aminium groups and the O atom of the phosphoryl groups and additional hydrogen bonds between the aminium groups and the chloride ligands are present. Furthermore, four of the six H atoms not involved in intra-molecular bonding of each cobalt(II) tetra-cation form weak hydrogen bonds to four adjacent tetra-chloridocobaltate(II) counter-anions. By these inter-molecular hydrogen bonds, one-dimensional polymeric strands are formed along the b-axis direction. The hydrogen bonding is analyzed using the graph-set method and the structural similarity with dpmaHCl is discussed.