Eu2MnGe4O12 crystallizes in the orthorhombic Cmme space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form EuO6 octahedra that share corners with eight equivalent Ge(1)O4 tetrahedra. In the second Eu site, Eu(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. Mn(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with eight equivalent Ge(1)O4 tetrahedra. Ge(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form GeO4 tetrahedra that share corners with two equivalent Eu(1)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, and corners with two equivalent Ge(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-70°. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Ge(1) atoms. In the second O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Eu(1) and two equivalent Ge(1) atoms. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Eu(2), one Mn(1), and one Ge(1) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Eu(1), one Eu(2), and one Ge(1) atom.
Eu2MnGe4O12 crystallizes in the orthorhombic Cmme space group. There are two inequivalent Eu sites. In the first Eu site, Eu(1) is bonded to two equivalent O(4) and four equivalent O(2) atoms to form EuO6 octahedra that share corners with eight equivalent Ge(1)O4 tetrahedra. Both Eu(1)-O(4) bond lengths are 2.54 Å. All Eu(1)-O(2) bond lengths are 2.33 Å. In the second Eu site, Eu(2) is bonded in a 8-coordinate geometry to four equivalent O(1) and four equivalent O(2) atoms. All Eu(2)-O(1) bond lengths are 2.51 Å. All Eu(2)-O(2) bond lengths are 2.42 Å. Mn(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form MnO6 octahedra that share corners with eight equivalent Ge(1)O4 tetrahedra. Both Mn(1)-O(3) bond lengths are 2.50 Å. All Mn(1)-O(1) bond lengths are 2.04 Å. Ge(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form GeO4 tetrahedra that share corners with two equivalent Eu(1)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, and corners with two equivalent Ge(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 46-70°. The Ge(1)-O(1) bond length is 1.77 Å. The Ge(1)-O(2) bond length is 1.74 Å. The Ge(1)-O(3) bond length is 1.81 Å. The Ge(1)-O(4) bond length is 1.84 Å. There are four inequivalent O sites. In the first O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Mn(1) and two equivalent Ge(1) atoms. In the second O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to one Eu(1) and two equivalent Ge(1) atoms. In the third O site, O(1) is bonded in a distorted trigonal planar geometry to one Eu(2), one Mn(1), and one Ge(1) atom. In the fourth O site, O(2) is bonded in a distorted trigonal planar geometry to one Eu(1), one Eu(2), and one Ge(1) atom.