MgMo2(PO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(8), and one O(9) atom to form MgO6 octahedra that share corners with two equivalent Mo(1)O6 octahedra; corners with four equivalent P(1,2)O4 tetrahedra; and faces with two equivalent Mo(2)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(6), and one O(7) atom to form MoO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra; corners with two equivalent Mo(2)O6 octahedra; and corners with four equivalent P(1,2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-51°. In the second Mo site, Mo(2) is bonded to one O(1), one O(2), one O(4), one O(5), one O(8), and one O(9) atom to form MoO6 octahedra that share corners with two equivalent Mo(1)O6 octahedra; corners with four equivalent P(1,2)O4 tetrahedra; and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 41°. P(1,2) is bonded to one O(3), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mo(1)O6 octahedra, and corners with two equivalent Mo(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-46°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Mo(1), and one Mo(2) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Mo(1), and one Mo(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom.
MgMo2(PO5)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(8), and one O(9) atom to form MgO6 octahedra that share corners with two equivalent Mo(1)O6 octahedra; corners with four equivalent P(1,2)O4 tetrahedra; and faces with two equivalent Mo(2)O6 octahedra. The corner-sharing octahedral tilt angles are 51°. The Mg(1)-O(1) bond length is 2.11 Å. The Mg(1)-O(2) bond length is 2.11 Å. The Mg(1)-O(4) bond length is 2.09 Å. The Mg(1)-O(5) bond length is 2.14 Å. The Mg(1)-O(8) bond length is 2.15 Å. The Mg(1)-O(9) bond length is 2.09 Å. There are two inequivalent Mo sites. In the first Mo site, Mo(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(6), and one O(7) atom to form MoO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra; corners with two equivalent Mo(2)O6 octahedra; and corners with four equivalent P(1,2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 41-51°. The Mo(1)-O(1) bond length is 2.02 Å. The Mo(1)-O(10) bond length is 2.12 Å. The Mo(1)-O(2) bond length is 2.02 Å. The Mo(1)-O(3) bond length is 2.12 Å. The Mo(1)-O(6) bond length is 2.05 Å. The Mo(1)-O(7) bond length is 2.05 Å. In the second Mo site, Mo(2) is bonded to one O(1), one O(2), one O(4), one O(5), one O(8), and one O(9) atom to form MoO6 octahedra that share corners with two equivalent Mo(1)O6 octahedra; corners with four equivalent P(1,2)O4 tetrahedra; and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles are 41°. The Mo(2)-O(1) bond length is 1.98 Å. The Mo(2)-O(2) bond length is 1.98 Å. The Mo(2)-O(4) bond length is 2.12 Å. The Mo(2)-O(5) bond length is 2.11 Å. The Mo(2)-O(8) bond length is 2.11 Å. The Mo(2)-O(9) bond length is 2.12 Å. P(1,2) is bonded to one O(3), one O(5), one O(7), and one O(9) atom to form PO4 tetrahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mo(1)O6 octahedra, and corners with two equivalent Mo(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 33-46°. The P(1,2)-O(3) bond length is 1.52 Å. The P(1,2)-O(5) bond length is 1.57 Å. The P(1,2)-O(7) bond length is 1.54 Å. The P(1,2)-O(9) bond length is 1.58 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Mg(1), one Mo(1), and one Mo(2) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Mg(1), one Mo(1), and one Mo(2) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. The O(4)-P(1,2) bond length is 1.58 Å. In the fifth O site, O(5) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. The O(6)-P(1,2) bond length is 1.54 Å. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. The O(8)-P(1,2) bond length is 1.57 Å. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Mg(1); one Mo(2); and one P(1,2) atom. In the tenth O site, O(10) is bonded in a bent 150 degrees geometry to one Mo(1) and one P(1,2) atom. The O(10)-P(1,2) bond length is 1.52 Å.