Synthesis and study of physicochemical properties of the magnesium heteropoly compound (NH4)4[MgMo6O18(OH)6] · 5H2O

The magnesium heteropoly compound (NH4)4[MgMo6O18(OH)6] · 5H2O (I) has been synthesized and studied by mass spectrometry, IR spectroscopy, X-ray powder diffraction, and thermogravimetry. Crystals of I are monoclinic, space group P21/n, a = 15.10 A, b = 11.64 A, c = 13.53 A, β = 74.28°, V = 2289.31 A3, ρcalc = 1.09 g/cm3, Z = 1.