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DOE OSTI · 1265107

Materials Data on Cd(BiO2)2 by Materials Project

Abstract

Bi2CdO4 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Cd2+ is bonded to six O2- atoms to form distorted CdO6 pentagonal pyramids that share corners with two equivalent CdO6 pentagonal pyramids, an edgeedge with one CdO6 pentagonal pyramid, and edges with four equivalent BiO5 square pyramids. There are two shorter (2.30 Å) and four longer (2.42 Å) Cd–O bond lengths. There are two inequivalent Bi3+ sites. In the first Bi3+ site, Bi3+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent O2- atoms. There are two shorter (2.14 Å) and two longer (2.37 Å) Bi–O bond lengths. In the second Bi3+ site, Bi3+ is bonded to five O2- atoms to form distorted BiO5 square pyramids that share corners with two equivalent BiO5 square pyramids and edges with four equivalent CdO6 pentagonal pyramids. There are a spread of Bi–O bond distances ranging from 2.10–2.62 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Cd2+ and one Bi3+ atom. In the second O2- site, O2- is bonded to two equivalent Cd2+ and two equivalent Bi3+ atoms to form distorted OCd2Bi2 tetrahedra that share corners with eight OCd2Bi2 tetrahedra and edges with two equivalent OCdBi3 tetrahedra. In the third O2- site, O2- is bonded to one Cd2+ and three Bi3+ atoms to form a mixture of distorted edge and corner-sharing OCdBi3 tetrahedra.

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2020-04-30. Materials Data on Cd(BiO2)2 by Materials Project. https://doi.org/10.17188/1265107

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36 MATERIALS SCIENCE↗