Crystal chemistry and X-ray diffraction patterns for Co(NixZn1−x)Nb4O12(x= 0.2, 0.4, 0.6, 0.8)

Abstract

X-ray reference powder patterns and structures have been determined for a series of cobalt-, nickel- and zinc-containing niobates, Co(NixZn1−x)Nb4O12(x= 0.2, 0.4, 0.6, 0.8). The Co(NixZn1−x)Nb4O12series crystallize in the space group ofPbcn, which is of the disordered columbite-type structure (α-PbO2). The lattice parameters range froma= 14.11190(13) to 14.1569(3) Å,b= 5.69965(6) to 5.71209(13) Å,c= 5.03332(5) to 5.03673(11) Å, andV= 404.844(8) to 407.296(17) Å3fromx= 0.8 to 0.2, respectively. Co(NixZn1−x)Nb4O12contains double zig-zag chains of NbO6octahedra and single chain of (Ni,Zn,Co)O6octahedra run parallel to thebc-plane. Within the same chain the NbO6octahedra share edges, while the adjacent NbO6chains are joined to each other through common oxygen corners. These double NbO6chains are further linked together along the [100]-direction through another (Co,Ni,Zn)O6units, via common oxygen corners. The edge-sharing (Co,Ni,Zn)O6also forms zig-zag chains along thec-axis. Powder X-ray diffraction patterns of this series of compounds have been submitted to be included in the Powder Diffraction File.