Crystal and molecular structure of chloro[dodeca(dimethylamino)-cyclohexaphosphazene-NNNN]-copper(II) dichlorocuprate(I), [N6P6(NMe2)12CuIICl]+ CuICl2–

Abstract

Crystals of [N₆P₆(NMe₂)₁₂Cu^IICl]⁺Cu ^ICl₂^– are monoclinic, a= 19·352(8), b= 8·690(6), c= 14·069(7)Å, β= 91·04(4)°, Z= 2, space group P2/n. The structure was determined with Mo-K_α diffractometer data from Patterson and electron-density maps; full-matrix least-squares refinement reduced R to 0·083 for 1103 observed reflexions. The cation is situated on a crystallographic C₂ axis, and has the copper(II) atom bonded to four nitrogen atoms of the phosphazene ring and to one chlorine atom, in a distorted square-pyramidal co-ordination, with the chlorine atom in the apical position. There are two distinct P–N bond distances, 1·62 and 1·55 Å, which are explicable in terms of π-bonding theory. The Cu^ICl₂⁺ ion is also situated on a crystallographic C₂ axis, and is linear, with Cu–Cl 2·11 Å.