KCeGeSe4 crystallizes in the monoclinic P2_1 space group. K(1) is bonded in a 8-coordinate geometry to one Se(3), two equivalent Se(2), two equivalent Se(4), and three equivalent Se(1) atoms. Ce(1) is bonded in a 7-coordinate geometry to one Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. Ge(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to three equivalent K(1), one Ce(1), and one Ge(1) atom. In the second Se site, Se(2) is bonded to two equivalent K(1), two equivalent Ce(1), and one Ge(1) atom to form a mixture of distorted edge, face, and corner-sharing SeK2Ce2Ge square pyramids. In the third Se site, Se(3) is bonded in a distorted see-saw-like geometry to one K(1), two equivalent Ce(1), and one Ge(1) atom. In the fourth Se site, Se(4) is bonded to two equivalent K(1), two equivalent Ce(1), and one Ge(1) atom to form a mixture of distorted edge, face, and corner-sharing SeK2Ce2Ge square pyramids.
KCeGeSe4 crystallizes in the monoclinic P2_1 space group. K(1) is bonded in a 8-coordinate geometry to one Se(3), two equivalent Se(2), two equivalent Se(4), and three equivalent Se(1) atoms. The K(1)-Se(3) bond length is 3.41 Å. There is one shorter (3.51 Å) and one longer (3.64 Å) K(1)-Se(2) bond length. There is one shorter (3.53 Å) and one longer (3.58 Å) K(1)-Se(4) bond length. There are a spread of K(1)-Se(1) bond distances ranging from 3.43-3.91 Å. Ce(1) is bonded in a 7-coordinate geometry to one Se(1), two equivalent Se(2), two equivalent Se(3), and two equivalent Se(4) atoms. The Ce(1)-Se(1) bond length is 3.01 Å. Both Ce(1)-Se(2) bond lengths are 3.07 Å. There is one shorter (3.05 Å) and one longer (3.17 Å) Ce(1)-Se(3) bond length. There is one shorter (3.10 Å) and one longer (3.12 Å) Ce(1)-Se(4) bond length. Ge(1) is bonded in a tetrahedral geometry to one Se(1), one Se(2), one Se(3), and one Se(4) atom. The Ge(1)-Se(1) bond length is 2.36 Å. The Ge(1)-Se(2) bond length is 2.39 Å. The Ge(1)-Se(3) bond length is 2.39 Å. The Ge(1)-Se(4) bond length is 2.39 Å. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 5-coordinate geometry to three equivalent K(1), one Ce(1), and one Ge(1) atom. In the second Se site, Se(2) is bonded to two equivalent K(1), two equivalent Ce(1), and one Ge(1) atom to form a mixture of distorted edge, face, and corner-sharing SeK2Ce2Ge square pyramids. In the third Se site, Se(3) is bonded in a distorted see-saw-like geometry to one K(1), two equivalent Ce(1), and one Ge(1) atom. In the fourth Se site, Se(4) is bonded to two equivalent K(1), two equivalent Ce(1), and one Ge(1) atom to form a mixture of distorted edge, face, and corner-sharing SeK2Ce2Ge square pyramids.