Zirconium phosphate Formula

The pyrophosphate of uranium(IV) has been obtained and the structure determined to belong to the ZrP207-type structure. " Octahedral sites in the zirconium phosphates can accommodate U, as exemplified by the Na dizirconium tris(phosphate) structural family ([NZP]). An end member in this study was monoclinic KU2Zr(P04)3, which contains nine-coordinate Compounds of the general formula MU2(P04)3 have been reported for... 

These authors measured the solubility of zirconium phosphate in hydrochloric acid solutions. Analysis of the compound used in the experiments was found to have the composition ZrH4P209, which the authors believed to be Zr0(H2P04)2, although they did acknowledge that the formula Zr(HP04)2-H20 was equally possible. They believed that the former compound formed when the zirconyl ion, ZrO, reacts with the phosphate ion. However, [56CLE/VAU] provided clear evidence for the absence of the zirconyl... 

The octahedral coordination arises from the fact that each Zr or Ti is coordinated by six different phosphate groups which requires that each phosphate group bridge three metal atoms. All the charge then resides on the fourth oxygen, which points into the interlayer and is bonded to a hydrogen atom. By comparison with an Sig smectite unit, the formula is (Zr4)oct(F8)tet 24( )8 Thus there is no substitution, either in the octahedra or the tetrahedra, and in this respect zirconium phosphate is more like a pyrophyllite than a smectite clay. The forces between layers are of the van der Waals type, and no swelling in water... 

Zirconium (titanium) phosphate sulfophenylphosphonates are members of the same family. Here, some of the phosphate groups are replaced by sul-fophenylphosphonate, giving a general formula ... 

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