CaIn4(Ge2O7)2 crystallizes in the trigonal R3m space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), three equivalent O(3), and three equivalent O(6) atoms. There are two inequivalent In sites. In the first In site, In(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), and two equivalent O(5) atoms. In the second In site, In(2) is bonded to one O(1), one O(2), three equivalent O(4), and three equivalent O(6) atoms to form distorted InO8 hexagonal bipyramids that share edges with six equivalent Ge(1)O6 octahedra. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form GeO6 octahedra that share corners with two equivalent Ge(2)O6 octahedra, corners with four equivalent Ge(1)O6 octahedra, and edges with two equivalent In(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-51°. In the second Ge site, Ge(2) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form corner-sharing GeO6 octahedra. The corner-sharing octahedral tilt angles range from 43-51°. There are six inequivalent O sites. In the first O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent In(1), one Ge(1), and one Ge(2) atom. In the second O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), one In(2), and two equivalent Ge(1) atoms. In the third O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one In(2) and three equivalent In(1) atoms. In the fourth O site, O(2) is bonded in a distorted trigonal bipyramidal geometry to one Ca(1), one In(2), and three equivalent In(1) atoms. In the fifth O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Ge(1), and one Ge(2) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one In(1), one In(2), and two equivalent Ge(1) atoms.
CaIn4(Ge2O7)2 crystallizes in the trigonal R3m space group. Ca(1) is bonded in a 7-coordinate geometry to one O(2), three equivalent O(3), and three equivalent O(6) atoms. The Ca(1)-O(2) bond length is 2.28 Å. All Ca(1)-O(3) bond lengths are 2.42 Å. All Ca(1)-O(6) bond lengths are 2.28 Å. There are two inequivalent In sites. In the first In site, In(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(4), and two equivalent O(5) atoms. The In(1)-O(1) bond length is 2.23 Å. The In(1)-O(2) bond length is 2.30 Å. The In(1)-O(4) bond length is 2.22 Å. Both In(1)-O(5) bond lengths are 2.27 Å. In the second In site, In(2) is bonded to one O(1), one O(2), three equivalent O(4), and three equivalent O(6) atoms to form distorted InO8 hexagonal bipyramids that share edges with six equivalent Ge(1)O6 octahedra. The In(2)-O(1) bond length is 2.20 Å. The In(2)-O(2) bond length is 2.31 Å. All In(2)-O(4) bond lengths are 2.56 Å. All In(2)-O(6) bond lengths are 2.46 Å. There are two inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(3), one O(5), two equivalent O(4), and two equivalent O(6) atoms to form GeO6 octahedra that share corners with two equivalent Ge(2)O6 octahedra, corners with four equivalent Ge(1)O6 octahedra, and edges with two equivalent In(2)O8 hexagonal bipyramids. The corner-sharing octahedral tilt angles range from 42-51°. The Ge(1)-O(3) bond length is 2.01 Å. The Ge(1)-O(5) bond length is 2.04 Å. Both Ge(1)-O(4) bond lengths are 1.90 Å. Both Ge(1)-O(6) bond lengths are 1.93 Å. In the second Ge site, Ge(2) is bonded to three equivalent O(3) and three equivalent O(5) atoms to form corner-sharing GeO6 octahedra. The corner-sharing octahedral tilt angles range from 43-51°. All Ge(2)-O(3) bond lengths are 1.97 Å. All Ge(2)-O(5) bond lengths are 2.11 Å. There are six inequivalent O sites. In the first O site, O(5) is bonded in a rectangular see-saw-like geometry to two equivalent In(1), one Ge(1), and one Ge(2) atom. In the second O site, O(6) is bonded in a 4-coordinate geometry to one Ca(1), one In(2), and two equivalent Ge(1) atoms. In the third O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one In(2) and three equivalent In(1) atoms. In the fourth O site, O(2) is bonded in a distorted trigonal bipyramidal geometry to one Ca(1), one In(2), and three equivalent In(1) atoms. In the fifth O site, O(3) is bonded in a 3-coordinate geometry to one Ca(1), one Ge(1), and one Ge(2) atom. In the sixth O site, O(4) is bonded in a 4-coordinate geometry to one In(1), one In(2), and two equivalent Ge(1) atoms.