LiFeGe2O6 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted LiO6 octahedra that share corners with two equivalent Ge(1)O4 tetrahedra, corners with four equivalent Ge(2)O4 tetrahedra, edges with three equivalent Fe(1)O6 octahedra, and  an edgeedge with one Ge(1)O4 tetrahedra. Fe(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with three equivalent Ge(1)O4 tetrahedra, corners with three equivalent Ge(2)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with three equivalent Li(1)O6 octahedra. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with two equivalent Li(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, and  an edgeedge with one Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-61°. In the second Ge site, Ge(2) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form GeO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with four equivalent Li(1)O6 octahedra, and corners with two equivalent Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-72°. There are six inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one Ge(2) atom. In the second O site, O(6) is bonded in a trigonal planar geometry to one Li(1) and two equivalent Ge(2) atoms. In the third O site, O(1) is bonded to one Li(1), two equivalent Fe(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OLiFe2Ge trigonal pyramids. In the fourth O site, O(2) is bonded in a T-shaped geometry to one Li(1), one Fe(1), and one Ge(1) atom. In the fifth O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1) and two equivalent Ge(1) atoms. In the sixth O site, O(4) is bonded to one Li(1), two equivalent Fe(1), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OLiFe2Ge tetrahedra.
LiFeGe2O6 crystallizes in the monoclinic P2_1/c space group. Li(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom to form distorted LiO6 octahedra that share corners with two equivalent Ge(1)O4 tetrahedra, corners with four equivalent Ge(2)O4 tetrahedra, edges with three equivalent Fe(1)O6 octahedra, and  an edgeedge with one Ge(1)O4 tetrahedra. The Li(1)-O(1) bond length is 2.16 Å. The Li(1)-O(2) bond length is 2.36 Å. The Li(1)-O(3) bond length is 2.22 Å. The Li(1)-O(4) bond length is 2.13 Å. The Li(1)-O(5) bond length is 2.09 Å. The Li(1)-O(6) bond length is 2.46 Å. Fe(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with three equivalent Ge(1)O4 tetrahedra, corners with three equivalent Ge(2)O4 tetrahedra, edges with two equivalent Fe(1)O6 octahedra, and edges with three equivalent Li(1)O6 octahedra. The Fe(1)-O(2) bond length is 1.93 Å. The Fe(1)-O(5) bond length is 1.97 Å. There is one shorter (2.06 Å) and one longer (2.15 Å) Fe(1)-O(1) bond length. There is one shorter (2.08 Å) and one longer (2.16 Å) Fe(1)-O(4) bond length. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(2), and two equivalent O(3) atoms to form GeO4 tetrahedra that share corners with two equivalent Li(1)O6 octahedra, corners with three equivalent Fe(1)O6 octahedra, corners with two equivalent Ge(1)O4 tetrahedra, and  an edgeedge with one Li(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 31-61°. The Ge(1)-O(1) bond length is 1.78 Å. The Ge(1)-O(2) bond length is 1.73 Å. There is one shorter (1.78 Å) and one longer (1.79 Å) Ge(1)-O(3) bond length. In the second Ge site, Ge(2) is bonded to one O(4), one O(5), and two equivalent O(6) atoms to form GeO4 tetrahedra that share corners with three equivalent Fe(1)O6 octahedra, corners with four equivalent Li(1)O6 octahedra, and corners with two equivalent Ge(2)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 49-72°. The Ge(2)-O(4) bond length is 1.79 Å. The Ge(2)-O(5) bond length is 1.74 Å. Both Ge(2)-O(6) bond lengths are 1.79 Å. There are six inequivalent O sites. In the first O site, O(5) is bonded in a distorted trigonal planar geometry to one Li(1), one Fe(1), and one Ge(2) atom. In the second O site, O(6) is bonded in a trigonal planar geometry to one Li(1) and two equivalent Ge(2) atoms. In the third O site, O(1) is bonded to one Li(1), two equivalent Fe(1), and one Ge(1) atom to form a mixture of distorted corner and edge-sharing OLiFe2Ge trigonal pyramids. In the fourth O site, O(2) is bonded in a T-shaped geometry to one Li(1), one Fe(1), and one Ge(1) atom. In the fifth O site, O(3) is bonded in a distorted trigonal planar geometry to one Li(1) and two equivalent Ge(1) atoms. In the sixth O site, O(4) is bonded to one Li(1), two equivalent Fe(1), and one Ge(2) atom to form a mixture of distorted corner and edge-sharing OLiFe2Ge tetrahedra.