CRYSTAL-STRUCTURE OF SPERMINIUM DIPHOSPHATE HEXAHYDRATE

The crystal and molecular structure of sperminium (4,9-diazoniadodecane-1,12-diammonium) diphosphate hexahydrate has been determined by single-crystal X-ray methods. The crystals are monoclinic, space group P2/c, with a = 1137.0(4), b = 708.2(3), c = 1513.4(3) pm, beta = 98.45(2)-degrees and Z = 2. The compound consists of fully protonated, centrosymmetric sperminium ions, diphosphate ions (P2O74-) and water molecules. The diphosphate ion has two-fold symmetry with O(1) on a two-fold axis. The P-O-P bond angle is 143.7(1)-degrees. The sperminium ion is hydrogen bonded mainly to the diphosphate ion.