ZnPCl7: a compositionally and structurally unprecedented metal-phospho-rus halide.

The synthesis and crystal structure of an unprecedented compound, zinc phospho-rus hepta-chloride or catena-poly[phospho-rus tetra-chloride [[di-chlor-ido-zinc]-μ-chlorido]], ZnPCl7 or {[PCl4][ZnCl3]} n , are reported. The reaction of ZnCl2 with PCl5 in a 1:1 molar ratio at 623 K produced single crystals of ZnPCl7, which crystallizes in the ortho-rhom-bic space group Ama2. The Zn and P atoms lie on crystallographic mirror planes, as do four of the Cl atoms. One Cl atom lies on a twofold axis and one occupies a general position. Its extended structure features isolated [PCl4]+ tetra-hedra and one-dimensional chains of corner-sharing ZnCl2Cl2/2 tetra-hedra. Bond-valence sum calculations support the assignment of formal oxidation states. This discovery extends the compositional and structural landscape of mixed-metal halides.