Cs2NbAgSe4 crystallizes in the orthorhombic Fddd space group. Cs(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. Nb(1) is bonded to four equivalent Se(1) atoms to form NbSe4 tetrahedra that share edges with two equivalent Ag(1)Se4 tetrahedra. Ag(1) is bonded to four equivalent Se(1) atoms to form distorted AgSe4 tetrahedra that share edges with two equivalent Nb(1)Se4 tetrahedra. Se(1) is bonded in a 6-coordinate geometry to four equivalent Cs(1), one Nb(1), and one Ag(1) atom.
Cs2NbAgSe4 crystallizes in the orthorhombic Fddd space group. Cs(1) is bonded in a 8-coordinate geometry to eight equivalent Se(1) atoms. There are a spread of Cs(1)-Se(1) bond distances ranging from 3.72-4.02 Å. Nb(1) is bonded to four equivalent Se(1) atoms to form NbSe4 tetrahedra that share edges with two equivalent Ag(1)Se4 tetrahedra. All Nb(1)-Se(1) bond lengths are 2.44 Å. Ag(1) is bonded to four equivalent Se(1) atoms to form distorted AgSe4 tetrahedra that share edges with two equivalent Nb(1)Se4 tetrahedra. All Ag(1)-Se(1) bond lengths are 2.67 Å. Se(1) is bonded in a 6-coordinate geometry to four equivalent Cs(1), one Nb(1), and one Ag(1) atom.