Cu2MgGeS4 is Stannite structured and crystallizes in the tetragonal I-42m space group. Mg(1) is bonded to four equivalent S(1) atoms to form MgS4 tetrahedra that share corners with four equivalent Ge(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. Cu(1) is bonded to four equivalent S(1) atoms to form CuS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra, and corners with four equivalent Ge(1)S4 tetrahedra. Ge(1) is bonded to four equivalent S(1) atoms to form GeS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. S(1) is bonded to one Mg(1), two equivalent Cu(1), and one Ge(1) atom to form corner-sharing SMgCu2Ge tetrahedra.
Cu2MgGeS4 is Stannite structured and crystallizes in the tetragonal I-42m space group. Mg(1) is bonded to four equivalent S(1) atoms to form MgS4 tetrahedra that share corners with four equivalent Ge(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. All Mg(1)-S(1) bond lengths are 2.48 Å. Cu(1) is bonded to four equivalent S(1) atoms to form CuS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra, corners with four equivalent Cu(1)S4 tetrahedra, and corners with four equivalent Ge(1)S4 tetrahedra. All Cu(1)-S(1) bond lengths are 2.31 Å. Ge(1) is bonded to four equivalent S(1) atoms to form GeS4 tetrahedra that share corners with four equivalent Mg(1)S4 tetrahedra and corners with eight equivalent Cu(1)S4 tetrahedra. All Ge(1)-S(1) bond lengths are 2.27 Å. S(1) is bonded to one Mg(1), two equivalent Cu(1), and one Ge(1) atom to form corner-sharing SMgCu2Ge tetrahedra.