1:1 CaO–Bi2O3 compound

Description

The crystal structure of the 1:1 CaO-Bi₂O₃ compound (CaBi₂O₄) has been determined by single-crystal X-ray and neutron powder diffraction techniques. The compound crystallizes with the symmetry of the monoclinic space group C2/c and lattice parameters a=16.6130 ? , b=11.5900 ? , c=13.9939 ? , b=134.048°.The structure consists of sheets parallel to the b-c plane and connected by Ca-O bonds. There is a structural unit in each layer consisting of four Bi atoms, ten oxygen atoms, and two calcium atoms. The Bi atoms are fourfold coordinated and the coordination polyhedron may be described as a short distorted pyramid, open on one end to accommodate the lonepair electrons of the bismuth atoms. Calcium is sevencoordinated and the coordination polyhedron may be described as a monocapped trigonal prism.