SYNTHESIS AND CRYSTAL-STRUCTURE OF CO(PO3OH).H2O

Syntheses under moderate hydrothermal conditions yielded single crystals of the compound Co(PO3OH).H2O: a = 15.956(3) angstrom, c = 7.703(2) angstrom, space group R3BAR, Z = 18. The crystal structure was determined from 932-X-ray reflections with sin-theta/lambda less-than-or-equal-to 0.70 angstrom-1; Refinement gave R = 0.032. Slightly distorted CoO6 octahedra (Co-O from 2.052(2) to 2.174(2) angstrom, <2.111 angstrom>) share two common O-O edges resulting in helical infinity 1 [CoO4] rows parallel to [001]. These rows are interconnected by protonated phosphate tetrahedra. Within the phosphate tetrahedron the P-O distance to the hydroxyl group is 1.585(2) angstrom, the three other P-O distances range from 1.519(2) to 1.530(2) angstrom. The hydrogen bonds line the surface of unoccupied channels of diameter 4.63 angstrom running in [001]; O-H...O range from 2.654(4) to 2.720(5) angstrom.