KEu(GeO3)4 crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(5) atoms to form distorted KO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with eight equivalent Eu(1)O12 cuboctahedra, and faces with eight equivalent Ge(1)O6 octahedra. Eu(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(4) atoms to form distorted EuO12 cuboctahedra that share corners with four equivalent Eu(1)O12 cuboctahedra, corners with eight equivalent K(1)O12 cuboctahedra, and faces with eight equivalent Ge(1)O6 octahedra. Ge(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form GeO6 octahedra that share corners with six equivalent Ge(1)O6 octahedra, faces with two equivalent K(1)O12 cuboctahedra, and faces with two equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-19°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one K(1), one Eu(1), and two equivalent Ge(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(1), one Eu(1), and two equivalent Ge(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one Eu(1), and two equivalent Ge(1) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Eu(1) and two equivalent Ge(1) atoms. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(1) and two equivalent Ge(1) atoms.
KEu(GeO3)4 crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(5) atoms to form distorted KO12 cuboctahedra that share corners with four equivalent K(1)O12 cuboctahedra, corners with eight equivalent Eu(1)O12 cuboctahedra, and faces with eight equivalent Ge(1)O6 octahedra. Both K(1)-O(2) bond lengths are 2.95 Å. Both K(1)-O(3) bond lengths are 3.01 Å. All K(1)-O(1) bond lengths are 2.88 Å. There are two shorter (2.70 Å) and two longer (2.74 Å) K(1)-O(5) bond lengths. Eu(1) is bonded to two equivalent O(2), two equivalent O(3), four equivalent O(1), and four equivalent O(4) atoms to form distorted EuO12 cuboctahedra that share corners with four equivalent Eu(1)O12 cuboctahedra, corners with eight equivalent K(1)O12 cuboctahedra, and faces with eight equivalent Ge(1)O6 octahedra. Both Eu(1)-O(2) bond lengths are 2.39 Å. Both Eu(1)-O(3) bond lengths are 2.55 Å. All Eu(1)-O(1) bond lengths are 2.54 Å. There are two shorter (2.54 Å) and two longer (2.89 Å) Eu(1)-O(4) bond lengths. Ge(1) is bonded to one O(2), one O(3), one O(4), one O(5), and two equivalent O(1) atoms to form GeO6 octahedra that share corners with six equivalent Ge(1)O6 octahedra, faces with two equivalent K(1)O12 cuboctahedra, and faces with two equivalent Eu(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 5-19°. The Ge(1)-O(2) bond length is 2.00 Å. The Ge(1)-O(3) bond length is 1.87 Å. The Ge(1)-O(4) bond length is 1.98 Å. The Ge(1)-O(5) bond length is 1.87 Å. There is one shorter (1.93 Å) and one longer (1.98 Å) Ge(1)-O(1) bond length. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted rectangular see-saw-like geometry to one K(1), one Eu(1), and two equivalent Ge(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to one K(1), one Eu(1), and two equivalent Ge(1) atoms. In the third O site, O(3) is bonded in a 2-coordinate geometry to one K(1), one Eu(1), and two equivalent Ge(1) atoms. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Eu(1) and two equivalent Ge(1) atoms. In the fifth O site, O(5) is bonded in a distorted rectangular see-saw-like geometry to two equivalent K(1) and two equivalent Ge(1) atoms.