CaGeO3 crystallizes in the triclinic P-1 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(7), one O(8), two equivalent O(5), and two equivalent O(9) atoms to form distorted CaO7 pentagonal bipyramids that share  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(2)O4 tetrahedra, corners with two equivalent Ge(3)O4 tetrahedra, edges with two equivalent Ca(2)O6 octahedra, edges with two equivalent Ca(3)O6 octahedra, edges with two equivalent Ca(1)O7 pentagonal bipyramids,  an edgeedge with one Ge(1)O4 tetrahedra, and  an edgeedge with one Ge(2)O4 tetrahedra. In the second Ca site, Ca(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form distorted CaO6 octahedra that share  a cornercorner with one Ge(2)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with three equivalent Ge(1)O4 tetrahedra, edges with two equivalent Ca(3)O6 octahedra, edges with two equivalent Ca(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(3)O4 tetrahedra. In the third Ca site, Ca(3) is bonded to one O(2), one O(3), one O(6), one O(7), one O(8), and one O(9) atom to form distorted CaO6 octahedra that share  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with three equivalent Ge(2)O4 tetrahedra, edges with two equivalent Ca(2)O6 octahedra, edges with two equivalent Ca(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(3)O4 tetrahedra. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form GeO4 tetrahedra that share  a cornercorner with one Ca(3)O6 octahedra, corners with three equivalent Ca(2)O6 octahedra,  a cornercorner with one Ca(1)O7 pentagonal bipyramid,  a cornercorner with one Ge(2)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 48-62°. In the second Ge site, Ge(2) is bonded to one O(1), one O(2), one O(6), and one O(9) atom to form GeO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra, corners with three equivalent Ca(3)O6 octahedra,  a cornercorner with one Ca(1)O7 pentagonal bipyramid,  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 45-63°. In the third Ge site, Ge(3) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form GeO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra,  a cornercorner with one Ca(3)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(2)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra, and  an edgeedge with one Ca(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-58°. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(1), one Ge(1), and one Ge(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(2), one Ca(3), and one Ge(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(2), one Ca(3), and one Ge(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(2), one Ge(1), and one Ge(3) atom. In the fifth O site, O(5) is bonded to one Ca(2), two equivalent Ca(1), and one Ge(1) atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(3), one Ge(2), and one Ge(3) atom. In the seventh O site, O(7) is bonded to one Ca(1), one Ca(2), one Ca(3), and one Ge(3) atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and one Ge(3) atom. In the ninth O site, O(9) is bonded to one Ca(3), two equivalent Ca(1), and one Ge(2) atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids.
CaGeO3 crystallizes in the triclinic P-1 space group. There are three inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), one O(7), one O(8), two equivalent O(5), and two equivalent O(9) atoms to form distorted CaO7 pentagonal bipyramids that share  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(2)O4 tetrahedra, corners with two equivalent Ge(3)O4 tetrahedra, edges with two equivalent Ca(2)O6 octahedra, edges with two equivalent Ca(3)O6 octahedra, edges with two equivalent Ca(1)O7 pentagonal bipyramids,  an edgeedge with one Ge(1)O4 tetrahedra, and  an edgeedge with one Ge(2)O4 tetrahedra. The Ca(1)-O(1) bond length is 2.53 Å. The Ca(1)-O(7) bond length is 2.33 Å. The Ca(1)-O(8) bond length is 2.44 Å. There is one shorter (2.36 Å) and one longer (2.52 Å) Ca(1)-O(5) bond length. There is one shorter (2.35 Å) and one longer (2.49 Å) Ca(1)-O(9) bond length. In the second Ca site, Ca(2) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(8) atom to form distorted CaO6 octahedra that share  a cornercorner with one Ge(2)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with three equivalent Ge(1)O4 tetrahedra, edges with two equivalent Ca(3)O6 octahedra, edges with two equivalent Ca(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(3)O4 tetrahedra. The Ca(2)-O(2) bond length is 2.38 Å. The Ca(2)-O(3) bond length is 2.35 Å. The Ca(2)-O(4) bond length is 2.40 Å. The Ca(2)-O(5) bond length is 2.32 Å. The Ca(2)-O(7) bond length is 2.44 Å. The Ca(2)-O(8) bond length is 2.50 Å. In the third Ca site, Ca(3) is bonded to one O(2), one O(3), one O(6), one O(7), one O(8), and one O(9) atom to form distorted CaO6 octahedra that share  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, corners with three equivalent Ge(2)O4 tetrahedra, edges with two equivalent Ca(2)O6 octahedra, edges with two equivalent Ca(1)O7 pentagonal bipyramids, and  an edgeedge with one Ge(3)O4 tetrahedra. The Ca(3)-O(2) bond length is 2.31 Å. The Ca(3)-O(3) bond length is 2.30 Å. The Ca(3)-O(6) bond length is 2.40 Å. The Ca(3)-O(7) bond length is 2.47 Å. The Ca(3)-O(8) bond length is 2.54 Å. The Ca(3)-O(9) bond length is 2.32 Å. There are three inequivalent Ge sites. In the first Ge site, Ge(1) is bonded to one O(1), one O(3), one O(4), and one O(5) atom to form GeO4 tetrahedra that share  a cornercorner with one Ca(3)O6 octahedra, corners with three equivalent Ca(2)O6 octahedra,  a cornercorner with one Ca(1)O7 pentagonal bipyramid,  a cornercorner with one Ge(2)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 48-62°. The Ge(1)-O(1) bond length is 1.76 Å. The Ge(1)-O(3) bond length is 1.72 Å. The Ge(1)-O(4) bond length is 1.78 Å. The Ge(1)-O(5) bond length is 1.74 Å. In the second Ge site, Ge(2) is bonded to one O(1), one O(2), one O(6), and one O(9) atom to form GeO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra, corners with three equivalent Ca(3)O6 octahedra,  a cornercorner with one Ca(1)O7 pentagonal bipyramid,  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(3)O4 tetrahedra, and  an edgeedge with one Ca(1)O7 pentagonal bipyramid. The corner-sharing octahedral tilt angles range from 45-63°. The Ge(2)-O(1) bond length is 1.77 Å. The Ge(2)-O(2) bond length is 1.71 Å. The Ge(2)-O(6) bond length is 1.79 Å. The Ge(2)-O(9) bond length is 1.74 Å. In the third Ge site, Ge(3) is bonded to one O(4), one O(6), one O(7), and one O(8) atom to form GeO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra,  a cornercorner with one Ca(3)O6 octahedra, corners with two equivalent Ca(1)O7 pentagonal bipyramids,  a cornercorner with one Ge(1)O4 tetrahedra,  a cornercorner with one Ge(2)O4 tetrahedra,  an edgeedge with one Ca(2)O6 octahedra, and  an edgeedge with one Ca(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 56-58°. The Ge(3)-O(4) bond length is 1.80 Å. The Ge(3)-O(6) bond length is 1.79 Å. The Ge(3)-O(7) bond length is 1.73 Å. The Ge(3)-O(8) bond length is 1.73 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Ca(1), one Ge(1), and one Ge(2) atom. In the second O site, O(2) is bonded in a distorted trigonal planar geometry to one Ca(2), one Ca(3), and one Ge(2) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(2), one Ca(3), and one Ge(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ca(2), one Ge(1), and one Ge(3) atom. In the fifth O site, O(5) is bonded to one Ca(2), two equivalent Ca(1), and one Ge(1) atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(3), one Ge(2), and one Ge(3) atom. In the seventh O site, O(7) is bonded to one Ca(1), one Ca(2), one Ca(3), and one Ge(3) atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids. In the eighth O site, O(8) is bonded in a 4-coordinate geometry to one Ca(1), one Ca(2), one Ca(3), and one Ge(3) atom. In the ninth O site, O(9) is bonded to one Ca(3), two equivalent Ca(1), and one Ge(2) atom to form a mixture of distorted edge and corner-sharing OCa3Ge trigonal pyramids.