Cs2Hg3Se4 crystallizes in the orthorhombic Ibam space group. Cs(1) is bonded in a 10-coordinate geometry to two equivalent Hg(2) and eight equivalent Se(1) atoms. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a tetrahedral geometry to four equivalent Se(1) atoms. In the second Hg site, Hg(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1) and two equivalent Se(1) atoms. Se(1) is bonded in a 2-coordinate geometry to four equivalent Cs(1), one Hg(1), and one Hg(2) atom.
Cs2Hg3Se4 crystallizes in the orthorhombic Ibam space group. Cs(1) is bonded in a 10-coordinate geometry to two equivalent Hg(2) and eight equivalent Se(1) atoms. Both Cs(1)-Hg(2) bond lengths are 4.13 Å. There are a spread of Cs(1)-Se(1) bond distances ranging from 3.75-4.05 Å. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a tetrahedral geometry to four equivalent Se(1) atoms. All Hg(1)-Se(1) bond lengths are 2.75 Å. In the second Hg site, Hg(2) is bonded in a distorted bent 150 degrees geometry to two equivalent Cs(1) and two equivalent Se(1) atoms. Both Hg(2)-Se(1) bond lengths are 2.52 Å. Se(1) is bonded in a 2-coordinate geometry to four equivalent Cs(1), one Hg(1), and one Hg(2) atom.