MgEu2VO4 crystallizes in the tetragonal I-4m2 space group. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. There are three inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 5-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. In the second Eu site, Eu(1) is bonded in a 5-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. In the third Eu site, Eu(1) is bonded in a 5-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. V(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted corner-sharing VO6 octahedra. The corner-sharing octahedral tilt angles are 8°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 8-coordinate geometry to two equivalent Mg(1); five Eu(1,1); and one V(1) atom. In the second O site, O(2) is bonded to four Eu(1,1) and two equivalent V(1) atoms to form a mixture of distorted edge, corner, and face-sharing OEu4V2 octahedra. The corner-sharing octahedral tilt angles are 8°.
MgEu2VO4 crystallizes in the tetragonal I-4m2 space group. Mg(1) is bonded in a 4-coordinate geometry to four equivalent O(1) atoms. All Mg(1)-O(1) bond lengths are 2.19 Å. There are three inequivalent Eu sites. In the first Eu site, Eu(1) is bonded in a 5-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. There are two shorter (2.46 Å) and two longer (2.63 Å) Eu(1)-O(2) bond lengths. There is one shorter (2.68 Å) and four longer (3.09 Å) Eu(1)-O(1) bond lengths. In the second Eu site, Eu(1) is bonded in a 5-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. There are two shorter (2.46 Å) and two longer (2.63 Å) Eu(1)-O(2) bond lengths. There is one shorter (2.68 Å) and four longer (3.09 Å) Eu(1)-O(1) bond lengths. In the third Eu site, Eu(1) is bonded in a 5-coordinate geometry to four equivalent O(2) and five equivalent O(1) atoms. There are two shorter (2.46 Å) and two longer (2.63 Å) Eu(1)-O(2) bond lengths. There is one shorter (2.68 Å) and four longer (3.09 Å) Eu(1)-O(1) bond lengths. V(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form distorted corner-sharing VO6 octahedra. The corner-sharing octahedral tilt angles are 8°. Both V(1)-O(1) bond lengths are 2.61 Å. All V(1)-O(2) bond lengths are 2.05 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a 8-coordinate geometry to two equivalent Mg(1); five Eu(1,1); and one V(1) atom. In the second O site, O(2) is bonded to four Eu(1,1) and two equivalent V(1) atoms to form a mixture of distorted edge, corner, and face-sharing OEu4V2 octahedra. The corner-sharing octahedral tilt angles are 8°.