Mg7GeN6 crystallizes in the orthorhombic Ibam space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted MgN4 tetrahedra that share corners with two equivalent Ge(1)N4 tetrahedra, corners with eight equivalent Mg(2)N4 trigonal pyramids,  an edgeedge with one Mg(1)N4 tetrahedra, and edges with two equivalent Mg(2)N4 trigonal pyramids. In the second Mg site, Mg(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted MgN4 trigonal pyramids that share corners with two equivalent Ge(1)N4 tetrahedra, corners with four equivalent Mg(1)N4 tetrahedra, corners with two equivalent Mg(2)N4 trigonal pyramids,  an edgeedge with one Mg(1)N4 tetrahedra, and edges with three equivalent Mg(2)N4 trigonal pyramids. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to four equivalent N(1) atoms. Ge(1) is bonded to four equivalent N(1) atoms to form GeN4 tetrahedra that share corners with four equivalent Mg(1)N4 tetrahedra and corners with eight equivalent Mg(2)N4 trigonal pyramids. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Mg(1), one Mg(3), two equivalent Mg(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing NMg4Ge trigonal bipyramids. In the second N site, N(2) is bonded in a 6-coordinate geometry to two equivalent Mg(1) and four equivalent Mg(2) atoms.
Mg7GeN6 crystallizes in the orthorhombic Ibam space group. There are three inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted MgN4 tetrahedra that share corners with two equivalent Ge(1)N4 tetrahedra, corners with eight equivalent Mg(2)N4 trigonal pyramids,  an edgeedge with one Mg(1)N4 tetrahedra, and edges with two equivalent Mg(2)N4 trigonal pyramids. Both Mg(1)-N(1) bond lengths are 2.14 Å. There is one shorter (2.09 Å) and one longer (2.32 Å) Mg(1)-N(2) bond length. In the second Mg site, Mg(2) is bonded to two equivalent N(1) and two equivalent N(2) atoms to form distorted MgN4 trigonal pyramids that share corners with two equivalent Ge(1)N4 tetrahedra, corners with four equivalent Mg(1)N4 tetrahedra, corners with two equivalent Mg(2)N4 trigonal pyramids,  an edgeedge with one Mg(1)N4 tetrahedra, and edges with three equivalent Mg(2)N4 trigonal pyramids. There is one shorter (2.10 Å) and one longer (2.16 Å) Mg(2)-N(1) bond length. There is one shorter (2.17 Å) and one longer (2.22 Å) Mg(2)-N(2) bond length. In the third Mg site, Mg(3) is bonded in a 4-coordinate geometry to four equivalent N(1) atoms. All Mg(3)-N(1) bond lengths are 2.20 Å. Ge(1) is bonded to four equivalent N(1) atoms to form GeN4 tetrahedra that share corners with four equivalent Mg(1)N4 tetrahedra and corners with eight equivalent Mg(2)N4 trigonal pyramids. All Ge(1)-N(1) bond lengths are 1.87 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded to one Mg(1), one Mg(3), two equivalent Mg(2), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing NMg4Ge trigonal bipyramids. In the second N site, N(2) is bonded in a 6-coordinate geometry to two equivalent Mg(1) and four equivalent Mg(2) atoms.