MgGa2O4 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(2) and three equivalent O(1) atoms to form MgO4 tetrahedra that share corners with three equivalent Mg(2)O6 octahedra and corners with nine equivalent Ga(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-59°. In the second Mg site, Mg(2) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form MgO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Ga(2)O4 tetrahedra, and edges with six equivalent Ga(1)O6 octahedra. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form GaO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Ga(2)O4 tetrahedra, edges with two equivalent Mg(2)O6 octahedra, and edges with four equivalent Ga(1)O6 octahedra. In the second Ga site, Ga(2) is bonded to one O(3) and three equivalent O(4) atoms to form GaO4 tetrahedra that share corners with three equivalent Mg(2)O6 octahedra and corners with nine equivalent Ga(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(2), and two equivalent Ga(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1) and three equivalent Ga(1) atoms. In the third O site, O(3) is bonded to one Ga(2) and three equivalent Ga(1) atoms to form a mixture of distorted corner and edge-sharing OGa4 trigonal pyramids. In the fourth O site, O(4) is bonded to one Mg(2), one Ga(2), and two equivalent Ga(1) atoms to form distorted OMgGa3 trigonal pyramids that share  a cornercorner with one O(3)Ga4 trigonal pyramid, corners with two equivalent O(4)MgGa3 trigonal pyramids,  an edgeedge with one O(3)Ga4 trigonal pyramid, and edges with two equivalent O(4)MgGa3 trigonal pyramids.
MgGa2O4 is Spinel-like structured and crystallizes in the trigonal R3m space group. There are two inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(2) and three equivalent O(1) atoms to form MgO4 tetrahedra that share corners with three equivalent Mg(2)O6 octahedra and corners with nine equivalent Ga(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-59°. The Mg(1)-O(2) bond length is 1.99 Å. All Mg(1)-O(1) bond lengths are 1.96 Å. In the second Mg site, Mg(2) is bonded to three equivalent O(1) and three equivalent O(4) atoms to form MgO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Ga(2)O4 tetrahedra, and edges with six equivalent Ga(1)O6 octahedra. All Mg(2)-O(1) bond lengths are 2.05 Å. All Mg(2)-O(4) bond lengths are 2.09 Å. There are two inequivalent Ga sites. In the first Ga site, Ga(1) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form GaO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Ga(2)O4 tetrahedra, edges with two equivalent Mg(2)O6 octahedra, and edges with four equivalent Ga(1)O6 octahedra. The Ga(1)-O(2) bond length is 2.01 Å. The Ga(1)-O(3) bond length is 2.09 Å. Both Ga(1)-O(1) bond lengths are 1.96 Å. Both Ga(1)-O(4) bond lengths are 2.06 Å. In the second Ga site, Ga(2) is bonded to one O(3) and three equivalent O(4) atoms to form GaO4 tetrahedra that share corners with three equivalent Mg(2)O6 octahedra and corners with nine equivalent Ga(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 57-59°. The Ga(2)-O(3) bond length is 1.97 Å. All Ga(2)-O(4) bond lengths are 1.91 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(2), and two equivalent Ga(1) atoms. In the second O site, O(2) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1) and three equivalent Ga(1) atoms. In the third O site, O(3) is bonded to one Ga(2) and three equivalent Ga(1) atoms to form a mixture of distorted corner and edge-sharing OGa4 trigonal pyramids. In the fourth O site, O(4) is bonded to one Mg(2), one Ga(2), and two equivalent Ga(1) atoms to form distorted OMgGa3 trigonal pyramids that share  a cornercorner with one O(3)Ga4 trigonal pyramid, corners with two equivalent O(4)MgGa3 trigonal pyramids,  an edgeedge with one O(3)Ga4 trigonal pyramid, and edges with two equivalent O(4)MgGa3 trigonal pyramids.