Chemical preparation, thermal behavior and infrared studies of the new cyclotriphosphate tetrahydrate of manganese and distrontium, MnSr2(P3O9)2.4H2O

Abstract

A new cyclotriphosphate tetrahydrate of manganese and distrontium, MnSr2(P3O9)2.4H2O, was obtained as a polycrystalline sample by the method of ion-exchange resin. The cyclotriphosphate studied in this work is the second one having the formula MnSr2(P3O9)2.4H2O after BaZn2(P3O9)2.10H2O. Its crystallographic characterization, infrared studies and thermal behavior are given. The studied phosphate crystallizes in the triclinic system, P-1, with the following unit cell parameters : a = 6,653(1)Å, b = 7,110(1)Å, c = 5,123(1)Å, a = 103,37(2)°, b = 95,81(2)°,  g = 93,04(2)° and Z = 1. The intermediate products of dehydration of MnSr2(P3O9)2.4H2O are MnSr2(P3O9)2.2H2O, mixture of ([Mn(PO3)2]∞ + 2g [Sr(PO3)2]∞) and mixture of ([Mn(PO3)2]∞ + 2b[Sr(PO3)2]∞). The thermal behavior of the studied condensed phosphate has been investigated and interpreted by IR absorption and X-ray diffraction experiments. The title compound can be used as catalyst, ion exchanger, the reactant in ionic conditions, intercalation reactions, superphosphate fertilizer and as an inorganic pigment in ceramics.