Crystal Structures of Dy2(WO4)3 and GdY(WO4)3

Two compounds, Dy2(WO4)3 and GdY(WO4)3, were synthesized by using the standard solid state reaction technique. The crystal structure was determined by powder X-ray diffraction and Rietveld refinement method. It is found that both compounds have Eu2(WO4)3-type monoclinic structure, with space group C 2/c, Z = 4. The unit cell parameters of Dy2(WO4)3 are a = 0.75981(1) nm. b = 1.13220( 1) nm, c = 1.13254( 1) nm, and β= 109.8001(3)°, and those of GdY(WO4)3 are a = 0.76175(1) nm, b = 1.13543(1) nm, c = 1.13496(2) nm, and bbbbbbbbbβwhile each rare-earth atom is surrounded by eight oxygen atoms. WO4 tetrahedra share their four vertices with REO8 (RE = Dy, Gd, or Y) trigondodecahedra and some REO8 trigondodecahedra share an edge with each other. The phase transition and the magnetic properties were investigated by differential thermal analysis (DTA) and dc superconducting quantum interference device (SQUID) magnetometer.