Na2MgGe2(SbO5)2 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(7), and one O(9) atom. Mg(1) is bonded to one O(1), one O(10), one O(6), and one O(8) atom to form distorted MgO4 trigonal pyramids that share  a cornercorner with one Sb(1)O6 octahedra, corners with three equivalent Sb(2)O5 square pyramids,  a cornercorner with one Ge(1)O4 tetrahedra, and  an edgeedge with one Ge(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles are 63°. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(10), one O(3), one O(4), and one O(9) atom to form GeO4 tetrahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O5 square pyramids, and  a cornercorner with one Mg(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 48-62°. In the second Ge site, Ge(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form distorted GeO4 trigonal pyramids that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O5 square pyramids, and  an edgeedge with one Mg(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 56-68°. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(9) atom to form SbO6 octahedra that share  a cornercorner with one Sb(2)O5 square pyramid, corners with two equivalent Ge(1)O4 tetrahedra,  a cornercorner with one Mg(1)O4 trigonal pyramid, and corners with two equivalent Ge(2)O4 trigonal pyramids. In the second Sb site, Sb(2) is bonded to one O(10), one O(2), one O(4), one O(6), and one O(8) atom to form distorted SbO5 square pyramids that share  a cornercorner with one Sb(1)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 trigonal pyramids, and corners with three equivalent Mg(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Mg(1), and one Sb(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(2), one Sb(1), and one Sb(2) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Ge(1), and one Sb(1) atom to form distorted ONa2GeSb trigonal pyramids that share  a cornercorner with one O(8)NaMgGeSb tetrahedra, corners with two equivalent O(10)NaMgGeSb tetrahedra,  a cornercorner with one O(5)Na2GeSb trigonal pyramid, and  an edgeedge with one O(5)Na2GeSb trigonal pyramid. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Na(2), one Ge(1), and one Sb(2) atom. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Ge(2), and one Sb(1) atom to form ONa2GeSb trigonal pyramids that share  a cornercorner with one O(10)NaMgGeSb tetrahedra, corners with two equivalent O(8)NaMgGeSb tetrahedra,  a cornercorner with one O(3)Na2GeSb trigonal pyramid, and  an edgeedge with one O(3)Na2GeSb trigonal pyramid. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), one Mg(1), one Ge(2), and one Sb(2) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ge(2), and one Sb(1) atom. In the eighth O site, O(8) is bonded to one Na(1), one Mg(1), one Ge(2), and one Sb(2) atom to form distorted ONaMgGeSb tetrahedra that share corners with two equivalent O(10)NaMgGeSb tetrahedra,  a cornercorner with one O(3)Na2GeSb trigonal pyramid, and corners with two equivalent O(5)Na2GeSb trigonal pyramids. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ge(1), and one Sb(1) atom. In the tenth O site, O(10) is bonded to one Na(2), one Mg(1), one Ge(1), and one Sb(2) atom to form distorted ONaMgGeSb tetrahedra that share corners with two equivalent O(8)NaMgGeSb tetrahedra,  a cornercorner with one O(5)Na2GeSb trigonal pyramid, and corners with two equivalent O(3)Na2GeSb trigonal pyramids.
Na2MgGe2(SbO5)2 crystallizes in the triclinic P1 space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. The Na(1)-O(1) bond length is 2.43 Å. The Na(1)-O(3) bond length is 2.63 Å. The Na(1)-O(5) bond length is 2.47 Å. The Na(1)-O(6) bond length is 2.45 Å. The Na(1)-O(7) bond length is 2.83 Å. The Na(1)-O(8) bond length is 2.52 Å. The Na(1)-O(9) bond length is 2.84 Å. In the second Na site, Na(2) is bonded in a 7-coordinate geometry to one O(10), one O(2), one O(3), one O(4), one O(5), one O(7), and one O(9) atom. The Na(2)-O(10) bond length is 2.36 Å. The Na(2)-O(2) bond length is 2.40 Å. The Na(2)-O(3) bond length is 2.51 Å. The Na(2)-O(4) bond length is 2.89 Å. The Na(2)-O(5) bond length is 2.48 Å. The Na(2)-O(7) bond length is 2.57 Å. The Na(2)-O(9) bond length is 2.82 Å. Mg(1) is bonded to one O(1), one O(10), one O(6), and one O(8) atom to form distorted MgO4 trigonal pyramids that share  a cornercorner with one Sb(1)O6 octahedra, corners with three equivalent Sb(2)O5 square pyramids,  a cornercorner with one Ge(1)O4 tetrahedra, and  an edgeedge with one Ge(2)O4 trigonal pyramid. The corner-sharing octahedral tilt angles are 63°. The Mg(1)-O(1) bond length is 1.97 Å. The Mg(1)-O(10) bond length is 1.92 Å. The Mg(1)-O(6) bond length is 2.04 Å. The Mg(1)-O(8) bond length is 2.11 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(10), one O(3), one O(4), and one O(9) atom to form GeO4 tetrahedra that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O5 square pyramids, and  a cornercorner with one Mg(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 48-62°. The Ge(1)-O(10) bond length is 1.76 Å. The Ge(1)-O(3) bond length is 1.80 Å. The Ge(1)-O(4) bond length is 1.78 Å. The Ge(1)-O(9) bond length is 1.80 Å. In the second Ge site, Ge(2) is bonded to one O(5), one O(6), one O(7), and one O(8) atom to form distorted GeO4 trigonal pyramids that share corners with two equivalent Sb(1)O6 octahedra, corners with two equivalent Sb(2)O5 square pyramids, and  an edgeedge with one Mg(1)O4 trigonal pyramid. The corner-sharing octahedral tilt angles range from 56-68°. The Ge(2)-O(5) bond length is 1.78 Å. The Ge(2)-O(6) bond length is 1.76 Å. The Ge(2)-O(7) bond length is 1.83 Å. The Ge(2)-O(8) bond length is 1.87 Å. There are two inequivalent Sb sites. In the first Sb site, Sb(1) is bonded to one O(1), one O(2), one O(3), one O(5), one O(7), and one O(9) atom to form SbO6 octahedra that share  a cornercorner with one Sb(2)O5 square pyramid, corners with two equivalent Ge(1)O4 tetrahedra,  a cornercorner with one Mg(1)O4 trigonal pyramid, and corners with two equivalent Ge(2)O4 trigonal pyramids. The Sb(1)-O(1) bond length is 1.93 Å. The Sb(1)-O(2) bond length is 2.00 Å. The Sb(1)-O(3) bond length is 2.05 Å. The Sb(1)-O(5) bond length is 2.11 Å. The Sb(1)-O(7) bond length is 2.06 Å. The Sb(1)-O(9) bond length is 2.04 Å. In the second Sb site, Sb(2) is bonded to one O(10), one O(2), one O(4), one O(6), and one O(8) atom to form distorted SbO5 square pyramids that share  a cornercorner with one Sb(1)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, corners with two equivalent Ge(2)O4 trigonal pyramids, and corners with three equivalent Mg(1)O4 trigonal pyramids. The corner-sharing octahedral tilt angles are 45°. The Sb(2)-O(10) bond length is 2.58 Å. The Sb(2)-O(2) bond length is 2.02 Å. The Sb(2)-O(4) bond length is 2.07 Å. The Sb(2)-O(6) bond length is 2.68 Å. The Sb(2)-O(8) bond length is 2.16 Å. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Na(1), one Mg(1), and one Sb(1) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Na(2), one Sb(1), and one Sb(2) atom. In the third O site, O(3) is bonded to one Na(1), one Na(2), one Ge(1), and one Sb(1) atom to form distorted ONa2GeSb trigonal pyramids that share  a cornercorner with one O(8)NaMgGeSb tetrahedra, corners with two equivalent O(10)NaMgGeSb tetrahedra,  a cornercorner with one O(5)Na2GeSb trigonal pyramid, and  an edgeedge with one O(5)Na2GeSb trigonal pyramid. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to one Na(2), one Ge(1), and one Sb(2) atom. In the fifth O site, O(5) is bonded to one Na(1), one Na(2), one Ge(2), and one Sb(1) atom to form ONa2GeSb trigonal pyramids that share  a cornercorner with one O(10)NaMgGeSb tetrahedra, corners with two equivalent O(8)NaMgGeSb tetrahedra,  a cornercorner with one O(3)Na2GeSb trigonal pyramid, and  an edgeedge with one O(3)Na2GeSb trigonal pyramid. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Na(1), one Mg(1), one Ge(2), and one Sb(2) atom. In the seventh O site, O(7) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ge(2), and one Sb(1) atom. In the eighth O site, O(8) is bonded to one Na(1), one Mg(1), one Ge(2), and one Sb(2) atom to form distorted ONaMgGeSb tetrahedra that share corners with two equivalent O(10)NaMgGeSb tetrahedra,  a cornercorner with one O(3)Na2GeSb trigonal pyramid, and corners with two equivalent O(5)Na2GeSb trigonal pyramids. In the ninth O site, O(9) is bonded in a distorted rectangular see-saw-like geometry to one Na(1), one Na(2), one Ge(1), and one Sb(1) atom. In the tenth O site, O(10) is bonded to one Na(2), one Mg(1), one Ge(1), and one Sb(2) atom to form distorted ONaMgGeSb tetrahedra that share corners with two equivalent O(8)NaMgGeSb tetrahedra,  a cornercorner with one O(5)Na2GeSb trigonal pyramid, and corners with two equivalent O(3)Na2GeSb trigonal pyramids.