Zn2Ge3O8 crystallizes in the cubic P4_332 space group. Zn(1) is bonded to one O(1) and three equivalent O(2) atoms to form ZnO4 tetrahedra that share corners with nine equivalent Ge(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-58°. Ge(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form GeO6 octahedra that share corners with six equivalent Zn(1)O4 tetrahedra and edges with four equivalent Ge(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Zn(1) and three equivalent Ge(1) atoms to form distorted corner-sharing OZnGe3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Zn(1) and two equivalent Ge(1) atoms.
Zn2Ge3O8 crystallizes in the cubic P4_332 space group. Zn(1) is bonded to one O(1) and three equivalent O(2) atoms to form ZnO4 tetrahedra that share corners with nine equivalent Ge(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-58°. The Zn(1)-O(1) bond length is 2.02 Å. All Zn(1)-O(2) bond lengths are 1.97 Å. Ge(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form GeO6 octahedra that share corners with six equivalent Zn(1)O4 tetrahedra and edges with four equivalent Ge(1)O6 octahedra. Both Ge(1)-O(1) bond lengths are 2.02 Å. There are two shorter (1.85 Å) and two longer (1.94 Å) Ge(1)-O(2) bond lengths. There are two inequivalent O sites. In the first O site, O(1) is bonded to one Zn(1) and three equivalent Ge(1) atoms to form distorted corner-sharing OZnGe3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Zn(1) and two equivalent Ge(1) atoms.