DOI: 10.17188/1322010
title: Materials Data on Ca(WO2)2 by Materials Project

description: Ca(WO2)2 is Spinel-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are eight inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to four O2- atoms to form CaO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 58–61°. There are a spread of Ca–O bond distances ranging from 2.20–2.32 Å. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with three CaO4 tetrahedra, corners with three WO4 tetrahedra, and edges with six WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.30–2.36 Å. In the third Ca2+ site, Ca2+ is bonded to four O2- atoms to form CaO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 56–65°. There are a spread of Ca–O bond distances ranging from 2.22–2.32 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with two equivalent CaO4 tetrahedra, corners with four WO4 tetrahedra, an edgeedge with one CaO6 octahedra, and edges with five WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.29–2.44 Å. In the fifth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six WO4 tetrahedra, edges with two CaO6 octahedra, and edges with four equivalent WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.35–2.39 Å. In the sixth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six WO4 tetrahedra, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.31–2.42 Å. In the seventh Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with five WO4 tetrahedra, an edgeedge with one CaO6 octahedra, and edges with five WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.28–2.38 Å. In the eighth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with six WO4 tetrahedra, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.33–2.41 Å. There are twelve inequivalent W3+ sites. In the first W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three CaO4 tetrahedra, corners with three WO4 tetrahedra, edges with two equivalent CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of W–O bond distances ranging from 2.14–2.26 Å. In the second W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three equivalent CaO4 tetrahedra, corners with three equivalent WO4 tetrahedra, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of W–O bond distances ranging from 2.15–2.29 Å. In the third W3+ site, W3+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with six CaO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 49–67°. There are a spread of W–O bond distances ranging from 2.02–2.07 Å. In the fourth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent CaO4 tetrahedra, corners with four WO4 tetrahedra, edges with three CaO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.14–2.26 Å. In the fifth W3+ site, W3+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 52–66°. There are a spread of W–O bond distances ranging from 2.08–2.16 Å. In the sixth W3+ site, W3+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with six CaO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 52–73°. There are a spread of W–O bond distances ranging from 2.14–2.19 Å. In the seventh W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six WO4 tetrahedra, edges with two equivalent WO6 octahedra, and edges with four CaO6 octahedra. There are a spread of W–O bond distances ranging from 2.15–2.24 Å. In the eighth W3+ site, W3+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with six CaO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 53–70°. There are a spread of W–O bond distances ranging from 2.12–2.20 Å. In the ninth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with five WO4 tetrahedra, edges with three CaO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.15–2.24 Å. In the tenth W3+ site, W3+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with six CaO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 48–70°. There are one shorter (2.04 Å) and three longer (2.09 Å) W–O bond lengths. In the eleventh W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three equivalent CaO4 tetrahedra, corners with three equivalent WO4 tetrahedra, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of W–O bond distances ranging from 2.14–2.23 Å. In the twelfth W3+ site, W3+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 56–60°. There are a spread of W–O bond distances ranging from 2.07–2.38 Å. There are twenty-four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two Ca2+ and two equivalent W3+ atoms. In the third O2- site, O2- is bonded to one Ca2+ and three W3+ atoms to form distorted OCaW3 trigonal pyramids that share a cornercorner with one OW4 tetrahedra and a cornercorner with one OCa2W2 trigonal pyramid. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to four W3+ atoms. In the fifth O2- site, O2- is bonded to two Ca2+ and two W3+ atoms to form distorted OCa2W2 trigonal pyramids that share a cornercorner with one OCaW3 tetrahedra, a cornercorner with one OCa2W2 trigonal pyramid, an edgeedge with one OCaW3 tetrahedra, and an edgeedge with one OCa2W2 trigonal pyramid. In the sixth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the eighth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the ninth O2- site, O2- is bonded to one Ca2+ and three W3+ atoms to form a mixture of distorted corner and edge-sharing OCaW3 tetrahedra. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the eleventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the thirteenth O2- site, O2- is bonded in a trigonal pyramidal geometry to one Ca2+ and three W3+ atoms. In the fourteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the fifteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the eighteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the nineteenth O2- site, O2- is bonded to two Ca2+ and two equivalent W3+ atoms to form distorted OCa2W2 trigonal pyramids that share corners with two equivalent OW4 tetrahedra and a cornercorner with one OCaW3 trigonal pyramid. In the twentieth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the twenty-first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the twenty-second O2- site, O2- is bonded to four W3+ atoms to form distorted corner-sharing OW4 tetrahedra. In the twenty-third O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the twenty-fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms.