NaCe(PSe3)2 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded in a 8-coordinate geometry to one Se(2), one Se(6), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(5) atoms. Ce(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(3), one Se(5), two equivalent Se(2), two equivalent Se(4), and two equivalent Se(6) atoms. There are two inequivalent P sites. In the first P site, P(1) is bonded in a distorted tetrahedral geometry to one P(2), one Se(1), one Se(2), and one Se(3) atom. In the second P site, P(2) is bonded in a distorted tetrahedral geometry to one P(1), one Se(4), one Se(5), and one Se(6) atom. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to two equivalent Na(1), one Ce(1), and one P(1) atom. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ce(1), and one P(1) atom. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ce(1), and one P(1) atom. In the fourth Se site, Se(4) is bonded in a distorted T-shaped geometry to two equivalent Ce(1) and one P(2) atom. In the fifth Se site, Se(5) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ce(1), and one P(2) atom. In the sixth Se site, Se(6) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ce(1), and one P(2) atom.
NaCe(PSe3)2 crystallizes in the monoclinic P2_1/c space group. Na(1) is bonded in a 8-coordinate geometry to one Se(2), one Se(6), two equivalent Se(1), two equivalent Se(3), and two equivalent Se(5) atoms. The Na(1)-Se(2) bond length is 3.14 Å. The Na(1)-Se(6) bond length is 3.46 Å. There is one shorter (3.34 Å) and one longer (3.59 Å) Na(1)-Se(1) bond length. There is one shorter (3.15 Å) and one longer (3.17 Å) Na(1)-Se(3) bond length. There is one shorter (3.12 Å) and one longer (3.42 Å) Na(1)-Se(5) bond length. Ce(1) is bonded in a 9-coordinate geometry to one Se(1), one Se(3), one Se(5), two equivalent Se(2), two equivalent Se(4), and two equivalent Se(6) atoms. The Ce(1)-Se(1) bond length is 3.06 Å. The Ce(1)-Se(3) bond length is 3.48 Å. The Ce(1)-Se(5) bond length is 3.09 Å. There is one shorter (3.12 Å) and one longer (3.36 Å) Ce(1)-Se(2) bond length. There is one shorter (3.13 Å) and one longer (3.15 Å) Ce(1)-Se(4) bond length. There is one shorter (3.22 Å) and one longer (3.25 Å) Ce(1)-Se(6) bond length. There are two inequivalent P sites. In the first P site, P(1) is bonded in a distorted tetrahedral geometry to one P(2), one Se(1), one Se(2), and one Se(3) atom. The P(1)-P(2) bond length is 2.26 Å. The P(1)-Se(1) bond length is 2.21 Å. The P(1)-Se(2) bond length is 2.21 Å. The P(1)-Se(3) bond length is 2.19 Å. In the second P site, P(2) is bonded in a distorted tetrahedral geometry to one P(1), one Se(4), one Se(5), and one Se(6) atom. The P(2)-Se(4) bond length is 2.23 Å. The P(2)-Se(5) bond length is 2.20 Å. The P(2)-Se(6) bond length is 2.22 Å. There are six inequivalent Se sites. In the first Se site, Se(1) is bonded in a 3-coordinate geometry to two equivalent Na(1), one Ce(1), and one P(1) atom. In the second Se site, Se(2) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ce(1), and one P(1) atom. In the third Se site, Se(3) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ce(1), and one P(1) atom. In the fourth Se site, Se(4) is bonded in a distorted T-shaped geometry to two equivalent Ce(1) and one P(2) atom. In the fifth Se site, Se(5) is bonded in a 4-coordinate geometry to two equivalent Na(1), one Ce(1), and one P(2) atom. In the sixth Se site, Se(6) is bonded in a 4-coordinate geometry to one Na(1), two equivalent Ce(1), and one P(2) atom.