MgY2Se4 crystallizes in the tetragonal I-42d space group. Mg(1) is bonded in a 4-coordinate geometry to eight equivalent Se(1) atoms. Y(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. Se(1) is bonded in a 6-coordinate geometry to two equivalent Mg(1) and four equivalent Y(1) atoms.
MgY2Se4 crystallizes in the tetragonal I-42d space group. Mg(1) is bonded in a 4-coordinate geometry to eight equivalent Se(1) atoms. There are four shorter (2.74 Å) and four longer (3.31 Å) Mg(1)-Se(1) bond lengths. Y(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. There are a spread of Y(1)-Se(1) bond distances ranging from 2.83-3.28 Å. Se(1) is bonded in a 6-coordinate geometry to two equivalent Mg(1) and four equivalent Y(1) atoms.