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WO2 is Cyanogen Chloride-derived structured and crystallizes in the hexagonal P6_3/mmc space group. The structure is zero-dimensional and consists of two tungsten;dihydrate molecules. W4+ is bonded in a linear geometry to two equivalent O2- atoms. Both W–O bond lengths are 1.80 Å. O2- is bonded in a single-bond geometry to one W4+ atom.
WO2 is Hydrophilite-like structured and crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent W4+ sites. In the first W4+ site, W4+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are a spread of W–O bond distances ranging from 2.04–2.14 Å. In the second W4+ site, W4+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing WO6 octahedra. The corner-sharing octahedra tilt angles range from 50–53°. There are a spread of W–O bond distances ranging from 2.04–2.14 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to three W4+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to three W4+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent W4+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent W4+ atoms.
Al(WO2)2 is Spinel structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. there are two inequivalent W+2.50+ sites. In the first W+2.50+ site, W+2.50+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six equivalent AlO4 tetrahedra and edges with six WO6 octahedra. There are four shorter (2.24 Å) and two longer (2.34 Å) W–O bond lengths. In the second W+2.50+ site, W+2.50+ is bonded to six equivalent O2- atoms to form WO6 octahedra that share corners with six equivalent AlO4 tetrahedra and edges with six equivalent WO6 octahedra. All W–O bond lengths are 2.19 Å. Al3+ is bonded to four O2- atoms to form AlO4 tetrahedra that share corners with twelve WO6 octahedra. The corner-sharing octahedra tilt angles range from 47–60°. There is one shorter (1.79 Å) and three longer (1.80 Å) Al–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to three W+2.50+ and one Al3+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to three equivalent W+2.50+ and one Al3+ atom.
Y(WO2)2 is Spinel structured and crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Y3+ is bonded to four O2- atoms to form YO4 tetrahedra that share corners with twelve WO6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. All Y–O bond lengths are 2.23 Å. There are two inequivalent W+2.50+ sites. In the first W+2.50+ site, W+2.50+ is bonded to six O2- atoms to form WO6 octahedra that share corners with six equivalent YO4 tetrahedra and edges with six WO6 octahedra. All W–O bond lengths are 2.23 Å. In the second W+2.50+ site, W+2.50+ is bonded to six equivalent O2- atoms to form WO6 octahedra that share corners with six equivalent YO4 tetrahedra and edges with six equivalent WO6 octahedra. All W–O bond lengths are 2.21 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to one Y3+ and three W+2.50+ atoms to form a mixture of distorted edge and corner-sharing OYW3 trigonal pyramids. In the second O2- site, O2- is bonded to one Y3+ and three equivalent W+2.50+ atoms to form a mixture of distorted edge and corner-sharing OYW3 tetrahedra.
Y(WO2)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Y3+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Y–O bond distances ranging from 2.34–2.52 Å. There are two inequivalent W+2.50+ sites. In the first W+2.50+ site, W+2.50+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.06 Å) and two longer (2.07 Å) W–O bond lengths. In the second W+2.50+ site, W+2.50+ is bonded in a distorted square co-planar geometry to four O2- atoms. There are two shorter (2.17 Å) and two longer (2.18 Å) W–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to two equivalent Y3+ and two W+2.50+ atoms to form a mixture of edge and corner-sharing OY2W2 tetrahedra. In the second O2- site, O2- is bonded to two equivalent Y3+ and two W+2.50+ atoms to form a mixture of edge and corner-sharing OY2W2 tetrahedra.
Mg(WO2)2 is Ilmenite-like structured and crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are six inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form MgO4 tetrahedra that share corners with three MgO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 53–61°. There are three shorter (2.04 Å) and one longer (2.13 Å) Mg–O bond lengths. In the second Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with six WO4 trigonal pyramids, edges with two MgO6 octahedra, and edges with four WO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.10–2.21 Å. In the third Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four WO4 trigonal pyramids, an edgeedge with one MgO6 octahedra, and edges with five WO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.12–2.16 Å. In the fourth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share edges with two MgO6 octahedra and edges with four WO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.11–2.18 Å. In the fifth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share corners with three WO4 trigonal pyramids, edges with two MgO6 octahedra, and edges with four equivalent WO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.09–2.17 Å. In the sixth Mg2+ site, Mg2+ is bonded to six O2- atoms to form MgO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, an edgeedge with one MgO6 octahedra, and edges with five WO6 octahedra. There are a spread of Mg–O bond distances ranging from 2.04–2.24 Å. There are nine inequivalent W3+ sites. In the first W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two equivalent MgO4 tetrahedra, corners with four WO4 trigonal pyramids, edges with three MgO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.17–2.22 Å. In the second W3+ site, W3+ is bonded to four O2- atoms to form WO4 trigonal pyramids that share corners with six MgO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 39–69°. There are a spread of W–O bond distances ranging from 2.01–2.55 Å. In the third W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three equivalent MgO4 tetrahedra, corners with three equivalent WO4 trigonal pyramids, edges with two MgO6 octahedra, and edges with four WO6 octahedra. There are a spread of W–O bond distances ranging from 2.15–2.18 Å. In the fourth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with three WO4 trigonal pyramids, edges with two equivalent WO6 octahedra, and edges with four MgO6 octahedra. There are a spread of W–O bond distances ranging from 2.15–2.25 Å. In the fifth W3+ site, W3+ is bonded in a trigonal planar geometry to three O2- atoms. All W–O bond lengths are 2.02 Å. In the sixth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share a cornercorner with one MgO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, edges with three MgO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.14–2.23 Å. In the seventh W3+ site, W3+ is bonded to four O2- atoms to form WO4 trigonal pyramids that share corners with six MgO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 39–69°. There are a spread of W–O bond distances ranging from 2.01–2.47 Å. In the eighth W3+ site, W3+ is bonded in a trigonal planar geometry to three O2- atoms. All W–O bond lengths are 2.02 Å. In the ninth W3+ site, W3+ is bonded to four O2- atoms to form WO4 trigonal pyramids that share corners with three MgO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 45–67°. There are a spread of W–O bond distances ranging from 2.00–2.38 Å. There are eighteen inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two W3+ atoms. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the third O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the fourth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two W3+ atoms. In the fifth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the sixth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent W3+ atoms. In the seventh O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two W3+ atoms. In the eighth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to one Mg2+ and three W3+ atoms. In the tenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two W3+ atoms. In the eleventh O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the twelfth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two W3+ atoms. In the thirteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Mg2+ and two equivalent W3+ atoms. In the fourteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the fifteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the sixteenth O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four W3+ atoms. In the seventeenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Mg2+ and three W3+ atoms. In the eighteenth O2- site, O2- is bonded in a 3-coordinate geometry to one Mg2+ and two equivalent W3+ atoms.
Ca(WO2)2 is beta indium sulfide-derived structured and crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are six 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 54–67°. There are three shorter (2.28 Å) and one longer (2.35 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with three equivalent WO4 trigonal pyramids, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.27–2.42 Å. In the third Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one WO4 tetrahedra, corners with two equivalent CaO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, an edgeedge with one CaO6 octahedra, and edges with five WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.31–2.42 Å. In the fourth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with three equivalent WO4 trigonal pyramids, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.30–2.41 Å. In the fifth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with two WO4 trigonal pyramids, edges with two CaO6 octahedra, and edges with four WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.22–2.49 Å. In the sixth Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with two equivalent WO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, an edgeedge with one CaO6 octahedra, and edges with five WO6 octahedra. There are a spread of Ca–O bond distances ranging from 2.27–2.41 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 a cornercorner with one WO4 tetrahedra, corners with two equivalent CaO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, edges with three CaO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.14–2.21 Å. In the second W3+ site, W3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of W–O bond distances ranging from 1.97–2.07 Å. In the third 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 2.06–2.27 Å. In the fourth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share a cornercorner with one WO4 tetrahedra, corners with two equivalent CaO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, edges with three CaO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.18–2.24 Å. In the fifth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two WO4 trigonal pyramids, 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 sixth W3+ site, W3+ is bonded to four O2- atoms to form WO4 trigonal pyramids that share corners with six CaO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 39–70°. There are a spread of W–O bond distances ranging from 1.97–2.36 Å. In the seventh W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share corners with two WO4 trigonal pyramids, edges with two equivalent WO6 octahedra, and edges with four CaO6 octahedra. There are a spread of W–O bond distances ranging from 2.00–2.23 Å. In the eighth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with two equivalent WO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, edges with three CaO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.14–2.22 Å. In the ninth W3+ site, W3+ is bonded to four O2- atoms to form WO4 trigonal pyramids that share corners with six CaO6 octahedra and corners with six WO6 octahedra. The corner-sharing octahedra tilt angles range from 43–79°. There are a spread of W–O bond distances ranging from 2.07–2.35 Å. In the tenth W3+ site, W3+ is bonded to six O2- atoms to form WO6 octahedra that share a cornercorner with one CaO4 tetrahedra, corners with two equivalent WO4 tetrahedra, corners with two equivalent WO4 trigonal pyramids, edges with three CaO6 octahedra, and edges with three WO6 octahedra. There are a spread of W–O bond distances ranging from 2.15–2.26 Å. In the eleventh W3+ site, W3+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of W–O bond distances ranging from 1.97–2.04 Å. In the twelfth W3+ site, W3+ is bonded to four O2- atoms to form distorted WO4 tetrahedra that share corners with three CaO6 octahedra and corners with nine WO6 octahedra. The corner-sharing octahedra tilt angles range from 51–75°. There are a spread of W–O bond distances ranging from 2.04–2.53 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 rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the third O2- site, O2- is bonded to two Ca2+ and two W3+ atoms to form distorted OCa2W2 tetrahedra that share corners with two OCa2W2 tetrahedra, corners with four OCaW3 trigonal pyramids, and an edgeedge with one OCaW3 tetrahedra. In the fourth O2- site, O2- is bonded to one Ca2+ and three W3+ atoms to form distorted OCaW3 tetrahedra that share corners with two OCa2W2 tetrahedra, corners with four OCaW3 trigonal pyramids, and an edgeedge with one OCa2W2 tetrahedra. In the fifth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. 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 two Ca2+ and two W3+ atoms. In the ninth O2- site, O2- is bonded in a trigonal non-coplanar geometry to two Ca2+ and one W3+ atom. In the tenth O2- site, O2- is bonded to one Ca2+ and three W3+ atoms to form OCaW3 trigonal pyramids that share corners with four OCa2W2 tetrahedra and corners with two OCaW3 trigonal pyramids. 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 rectangular see-saw-like geometry to two Ca2+ and two 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 3-coordinate geometry to two Ca2+ and one W3+ atom. In the sixteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the seventeenth O2- site, O2- is bonded to two Ca2+ and two W3+ atoms to form distorted OCa2W2 tetrahedra that share corners with two OCa2W2 tetrahedra and corners with four OCaW3 trigonal pyramids. In the eighteenth O2- site, O2- is bonded in a trigonal pyramidal geometry to one Ca2+ and three W3+ atoms. In the nineteenth O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the twentieth O2- site, O2- is bonded in a rectangular see-saw-like geometry to two Ca2+ and two W3+ atoms. In the twenty-first O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to four W3+ atoms. In the twenty-second O2- site, O2- is bonded to one Ca2+ and three W3+ atoms to form distorted OCaW3 trigonal pyramids that share corners with four OCa2W2 tetrahedra, corners with two OCaW3 trigonal pyramids, and an edgeedge with one OCaW3 trigonal pyramid. 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 to one Ca2+ and three W3+ atoms to form distorted OCaW3 trigonal pyramids that share corners with four OCa2W2 tetrahedra, corners with two OCaW3 trigonal pyramids, and an edgeedge with one OCaW3 trigonal pyramid.
Ca(WO2)2 is beta indium sulfide-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are two inequivalent Ca2+ sites. In the first Ca2+ site, Ca2+ is bonded to four O2- atoms to form CaO4 tetrahedra that share corners with three equivalent CaO6 octahedra and corners with nine equivalent WO6 octahedra. The corner-sharing octahedra tilt angles range from 56–65°. There are three shorter (2.27 Å) and one longer (2.32 Å) Ca–O bond lengths. In the second Ca2+ site, Ca2+ is bonded to six O2- atoms to form CaO6 octahedra that share corners with three equivalent CaO4 tetrahedra and edges with six equivalent WO6 octahedra. There are three shorter (2.34 Å) and three longer (2.39 Å) Ca–O bond lengths. There are two inequivalent W3+ sites. In the first W3+ site, W3+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. All W–O bond lengths are 2.02 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, edges with two equivalent CaO6 octahedra, and edges with four equivalent WO6 octahedra. There are a spread of W–O bond distances ranging from 2.16–2.27 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a rectangular see-saw-like geometry to one Ca2+ and three W3+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three equivalent W3+ atoms. In the third O2- site, O2- is bonded to one Ca2+ and three equivalent W3+ atoms to form a mixture of distorted edge and corner-sharing OCaW3 tetrahedra. In the fourth O2- site, O2- is bonded to two Ca2+ and two equivalent W3+ atoms to form distorted OCa2W2 trigonal pyramids that share a cornercorner with one OCaW3 tetrahedra, corners with two equivalent OCa2W2 trigonal pyramids, an edgeedge with one OCaW3 tetrahedra, and edges with two equivalent OCa2W2 trigonal pyramids.
Computed materials data using density functional theory calculations. These calculations determine the electronic structure of bulk materials by solving approximations to the Schrodinger equation. For more information, see https://materialsproject.org/docs/calculations