MgYMo3O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(4), one O(6), and one O(7) atom. Y(1) is bonded to one O(1), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form YO6 octahedra that share corners with four equivalent Mo(1)O6 octahedra, corners with four equivalent Mo(2)O6 octahedra, and corners with four equivalent Mo(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra, edges with two equivalent Mo(2)O6 octahedra, and edges with two equivalent Mo(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-53°. In the second Mo site, Mo(2) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra, edges with two equivalent Mo(1)O6 octahedra, and edges with two equivalent Mo(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. In the third Mo site, Mo(3) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(8) atom to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra, edges with two equivalent Mo(1)O6 octahedra, and edges with two equivalent Mo(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Y(1), one Mo(2), and one Mo(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mo(1), one Mo(2), and one Mo(3) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Y(1), one Mo(1), and one Mo(2) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Y(1), one Mo(1), and one Mo(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Y(1), one Mo(1), and one Mo(2) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Mg(1), one Mo(1), one Mo(2), and one Mo(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Y(1), one Mo(2), and one Mo(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Y(1), one Mo(1), and one Mo(3) atom.
MgYMo3O8 crystallizes in the triclinic P1 space group. Mg(1) is bonded in a distorted rectangular see-saw-like geometry to one O(3), one O(4), one O(6), and one O(7) atom. The Mg(1)-O(3) bond length is 1.96 Å. The Mg(1)-O(4) bond length is 1.96 Å. The Mg(1)-O(6) bond length is 1.87 Å. The Mg(1)-O(7) bond length is 1.97 Å. Y(1) is bonded to one O(1), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form YO6 octahedra that share corners with four equivalent Mo(1)O6 octahedra, corners with four equivalent Mo(2)O6 octahedra, and corners with four equivalent Mo(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. The Y(1)-O(1) bond length is 2.31 Å. The Y(1)-O(3) bond length is 2.38 Å. The Y(1)-O(4) bond length is 2.36 Å. The Y(1)-O(5) bond length is 2.38 Å. The Y(1)-O(7) bond length is 2.39 Å. The Y(1)-O(8) bond length is 2.35 Å. There are three inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(8) atom to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra, edges with two equivalent Mo(2)O6 octahedra, and edges with two equivalent Mo(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-53°. The Mo(1)-O(2) bond length is 2.09 Å. The Mo(1)-O(3) bond length is 2.18 Å. The Mo(1)-O(4) bond length is 2.17 Å. The Mo(1)-O(5) bond length is 2.00 Å. The Mo(1)-O(6) bond length is 2.14 Å. The Mo(1)-O(8) bond length is 1.99 Å. In the second Mo site, Mo(2) is bonded to one O(1), one O(2), one O(3), one O(5), one O(6), and one O(7) atom to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra, edges with two equivalent Mo(1)O6 octahedra, and edges with two equivalent Mo(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-54°. The Mo(2)-O(1) bond length is 2.02 Å. The Mo(2)-O(2) bond length is 1.99 Å. The Mo(2)-O(3) bond length is 2.23 Å. The Mo(2)-O(5) bond length is 2.15 Å. The Mo(2)-O(6) bond length is 2.09 Å. The Mo(2)-O(7) bond length is 2.16 Å. In the third Mo site, Mo(3) is bonded to one O(1), one O(2), one O(4), one O(6), one O(7), and one O(8) atom to form MoO6 octahedra that share corners with four equivalent Y(1)O6 octahedra, edges with two equivalent Mo(1)O6 octahedra, and edges with two equivalent Mo(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 50-54°. The Mo(3)-O(1) bond length is 2.18 Å. The Mo(3)-O(2) bond length is 2.13 Å. The Mo(3)-O(4) bond length is 2.23 Å. The Mo(3)-O(6) bond length is 2.14 Å. The Mo(3)-O(7) bond length is 2.22 Å. The Mo(3)-O(8) bond length is 2.16 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Y(1), one Mo(2), and one Mo(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mo(1), one Mo(2), and one Mo(3) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Y(1), one Mo(1), and one Mo(2) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Y(1), one Mo(1), and one Mo(3) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Y(1), one Mo(1), and one Mo(2) atom. In the sixth O site, O(6) is bonded in a distorted tetrahedral geometry to one Mg(1), one Mo(1), one Mo(2), and one Mo(3) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Y(1), one Mo(2), and one Mo(3) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Y(1), one Mo(1), and one Mo(3) atom.