SYNTHESIS AND CHARACTERIZATION OF (ZN,M)2P2O7 (M=MN, CU)

Characterization of powder samples of Zn2-xMxP2O7 (M = Mn, Cu; x = 0-2 ) shows that substitution of small amounts of Cu or Mn into low temper ature or alpha-Zn2P2O7 stabilizes a solid form isostructural with beta -Zn2P2O7, the high temperature form. Single crystal X-ray analysis of ZnCuP2O7; monoclinic space group C2/m, a = 6.741(5), b = 8.190(4), c = 4.542(3), beta = 107.72(5)-degrees, D(calc) = 4.210 g CM-3, Z = 2, R = 6.6% for 353 observed reflections; shows mixed metal sites with 50% occupancy each of Zn and Cu. Octahedrally coordinated metal atoms lie on planes in hexagonal array with two oxygen atoms bridging adjacent m etal sites. Magnetic susceptibility measurements of ZnMP2O7, M = Mn, C u show antiferromagnetic interactions between cations which are strong er for M = Cu.