Zr9W4O3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a distorted bent 150 degrees geometry to two equivalent W(1) and two equivalent O(1) atoms. In the second Zr site, Zr(2) is bonded in a 2-coordinate geometry to one W(2), three equivalent W(1), and two equivalent O(1) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded in a 12-coordinate geometry to two equivalent Zr(1), six equivalent Zr(2), two equivalent W(1), and two equivalent W(2) atoms. In the second W site, W(2) is bonded to six equivalent Zr(2) and six equivalent W(1) atoms to form WZr6W6 cuboctahedra that share edges with six equivalent O(1)Zr6 octahedra and faces with two equivalent W(2)Zr6W6 cuboctahedra. O(1) is bonded to two equivalent Zr(1) and four equivalent Zr(2) atoms to form OZr6 octahedra that share corners with six equivalent O(1)Zr6 octahedra and edges with two equivalent W(2)Zr6W6 cuboctahedra. The corner-sharing octahedral tilt angles range from 37-43°.
Zr9W4O3 crystallizes in the hexagonal P6_3/mmc space group. There are two inequivalent Zr sites. In the first Zr site, Zr(1) is bonded in a distorted bent 150 degrees geometry to two equivalent W(1) and two equivalent O(1) atoms. Both Zr(1)-W(1) bond lengths are 2.95 Å. Both Zr(1)-O(1) bond lengths are 2.26 Å. In the second Zr site, Zr(2) is bonded in a 2-coordinate geometry to one W(2), three equivalent W(1), and two equivalent O(1) atoms. The Zr(2)-W(2) bond length is 3.17 Å. There is one shorter (3.07 Å) and two longer (3.15 Å) Zr(2)-W(1) bond lengths. Both Zr(2)-O(1) bond lengths are 2.36 Å. There are two inequivalent W sites. In the first W site, W(1) is bonded in a 12-coordinate geometry to two equivalent Zr(1), six equivalent Zr(2), two equivalent W(1), and two equivalent W(2) atoms. Both W(1)-W(1) bond lengths are 2.88 Å. Both W(1)-W(2) bond lengths are 2.72 Å. In the second W site, W(2) is bonded to six equivalent Zr(2) and six equivalent W(1) atoms to form WZr6W6 cuboctahedra that share edges with six equivalent O(1)Zr6 octahedra and faces with two equivalent W(2)Zr6W6 cuboctahedra. O(1) is bonded to two equivalent Zr(1) and four equivalent Zr(2) atoms to form OZr6 octahedra that share corners with six equivalent O(1)Zr6 octahedra and edges with two equivalent W(2)Zr6W6 cuboctahedra. The corner-sharing octahedral tilt angles range from 37-43°.