STRUCTURE REFINEMENT OF CO3(OH)2(PO3OH)2 AND CO[PO2(OH)2]2.2H2O

Tricobalt dihydroxide bis(hydrogenphosphate), CO3(OH)2(PO3OH)2, M(r) = 402.77, monoclinic, P2(1)/c, a = 7.524 (2), b = 7.512 (2), c 7.395 (2) angstrom, beta = 117.88 (2)-degrees, V = 369.5 (1) angstrom3 , Z = 2, D(x) = 3.621 Mg m-3, lambda(Mo Kalpha) = 0.71073 angstrom, mu = 6.9 mm-1, F(000) = 390, room temperature, wR(F) = 0.027 for 2049 reflections. The structure is closely related to that of lazulite, MgAl2(OH)2(PO4)2. Cobalt bis(dihydrogenphosphate) dihydrate, Co[PO2(OH)2]2.2H2O, M(r) = 288.94, monoclinic, P2(1)/n, a = 7.268 (2), b = 9.886 (3), c = 5.331 (1) angstrom, beta = 94.86 (2)-degrees, V = 381.7 (1) angstrom3, Z = 2, D(x) = 2.514 Mg m-3, lambda(Mo Kalpha) = 0.71073 angstrom, mu = 2.56 mm-1, F(000) = 290, room temperature, wR(F) = 0.028 for 1678 reflections. A member of the M[PO2(OH)2]2.2H2O-type structures with M = Mg, Mn, Fe, Co or Cd.