Synthesis of Cu3(PO4)2 • H2O based solid solutions through Co or Ni substitution for Cu

New substitutional solid solutions have been synthesized: (Cu1-xCox)(3)(PO4)(2)center dot H2O (0 < x <= 0.20), (Cu1-xNix)(3)(PO4)(2)center dot H2O (0 < x <= 0.12), and (Cu1-yCoy)(3)(PO4)(2)center dot H2O (0.55 <= y <= 0.65). The first two solid solutions are isostructural with Cu-3(PO4)(2)center dot H2O (monoclinic symmetry, sp. gr. C2/c); the third solid solution also has a monoclinic structure, which is a Cu-3(PO4)(2)center dot H2O related superstructure. The lattice parameter b of (Cu1-yCoy)(3)(PO4)(2)center dot H2O (0.55 <= y <= 0.65) is almost twice that of (Cu1-xCox)(3)(PO4)(2)center dot H2O (0 < x <= 0.20), while their a and c parameters differ little. The solid solutions have been characterized by chemical analysis, x-ray diffraction, IR spectroscopy, and thermal analysis.