Cs2Re2Se5 crystallizes in the trigonal R-3c space group. Cs(1) is bonded in a 9-coordinate geometry to one Se(3), one Se(4), three equivalent Se(2), and four equivalent Se(1) atoms. Re(1) is bonded to one Se(1), one Se(3), and three equivalent Se(2) atoms to form distorted edge-sharing ReSe5 square pyramids. There are four inequivalent Se sites. In the first Se site, Se(4) is bonded to six equivalent Cs(1) atoms to form distorted face-sharing SeCs6 pentagonal pyramids. In the second Se site, Se(1) is bonded in a 1-coordinate geometry to four equivalent Cs(1) and one Re(1) atom. In the third Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent Cs(1) and three equivalent Re(1) atoms. In the fourth Se site, Se(3) is bonded to three equivalent Cs(1) and three equivalent Re(1) atoms to form distorted face-sharing SeCs3Re3 octahedra.
Cs2Re2Se5 crystallizes in the trigonal R-3c space group. Cs(1) is bonded in a 9-coordinate geometry to one Se(3), one Se(4), three equivalent Se(2), and four equivalent Se(1) atoms. The Cs(1)-Se(3) bond length is 3.62 Å. The Cs(1)-Se(4) bond length is 3.78 Å. There are a spread of Cs(1)-Se(2) bond distances ranging from 3.79-4.17 Å. There are a spread of Cs(1)-Se(1) bond distances ranging from 3.63-4.26 Å. Re(1) is bonded to one Se(1), one Se(3), and three equivalent Se(2) atoms to form distorted edge-sharing ReSe5 square pyramids. The Re(1)-Se(1) bond length is 2.61 Å. The Re(1)-Se(3) bond length is 2.55 Å. There is one shorter (2.54 Å) and two longer (2.55 Å) Re(1)-Se(2) bond lengths. There are four inequivalent Se sites. In the first Se site, Se(4) is bonded to six equivalent Cs(1) atoms to form distorted face-sharing SeCs6 pentagonal pyramids. In the second Se site, Se(1) is bonded in a 1-coordinate geometry to four equivalent Cs(1) and one Re(1) atom. In the third Se site, Se(2) is bonded in a 6-coordinate geometry to three equivalent Cs(1) and three equivalent Re(1) atoms. In the fourth Se site, Se(3) is bonded to three equivalent Cs(1) and three equivalent Re(1) atoms to form distorted face-sharing SeCs3Re3 octahedra.