KNa4Cl5 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. K(1) is bonded to two equivalent Cl(1) and four equivalent Cl(2) atoms to form KCl6 octahedra that share corners with two equivalent Na(1)Cl6 octahedra, corners with four equivalent Na(2)Cl6 octahedra, edges with two equivalent K(1)Cl6 octahedra, edges with four equivalent Na(1)Cl6 octahedra, and edges with six equivalent Na(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 3-5°. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one Cl(2), two equivalent Cl(3), and three equivalent Cl(1) atoms to form NaCl6 octahedra that share  a cornercorner with one K(1)Cl6 octahedra, corners with two equivalent Na(1)Cl6 octahedra, corners with three equivalent Na(2)Cl6 octahedra, edges with two equivalent K(1)Cl6 octahedra, edges with five equivalent Na(1)Cl6 octahedra, and edges with five equivalent Na(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. In the second Na site, Na(2) is bonded to one Cl(3), two equivalent Cl(1), and three equivalent Cl(2) atoms to form NaCl6 octahedra that share  a cornercorner with one Na(2)Cl6 octahedra, corners with two equivalent K(1)Cl6 octahedra, corners with three equivalent Na(1)Cl6 octahedra, edges with three equivalent K(1)Cl6 octahedra, edges with four equivalent Na(2)Cl6 octahedra, and edges with five equivalent Na(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to one K(1), two equivalent Na(2), and three equivalent Na(1) atoms to form ClKNa5 octahedra that share  a cornercorner with one Cl(1)KNa5 octahedra, corners with two equivalent Cl(3)Na6 octahedra, corners with three equivalent Cl(2)K2Na4 octahedra, edges with three equivalent Cl(3)Na6 octahedra, edges with four equivalent Cl(1)KNa5 octahedra, and edges with five equivalent Cl(2)K2Na4 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Cl site, Cl(2) is bonded to two equivalent K(1), one Na(1), and three equivalent Na(2) atoms to form ClK2Na4 octahedra that share  a cornercorner with one Cl(3)Na6 octahedra, corners with two equivalent Cl(2)K2Na4 octahedra, corners with three equivalent Cl(1)KNa5 octahedra, edges with two equivalent Cl(3)Na6 octahedra, edges with five equivalent Cl(2)K2Na4 octahedra, and edges with five equivalent Cl(1)KNa5 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the third Cl site, Cl(3) is bonded to two equivalent Na(2) and four equivalent Na(1) atoms to form ClNa6 octahedra that share corners with two equivalent Cl(2)K2Na4 octahedra, corners with four equivalent Cl(1)KNa5 octahedra, edges with two equivalent Cl(3)Na6 octahedra, edges with four equivalent Cl(2)K2Na4 octahedra, and edges with six equivalent Cl(1)KNa5 octahedra. The corner-sharing octahedral tilt angles range from 3-7°.
KNa4Cl5 is Caswellsilverite-like structured and crystallizes in the monoclinic C2/m space group. K(1) is bonded to two equivalent Cl(1) and four equivalent Cl(2) atoms to form KCl6 octahedra that share corners with two equivalent Na(1)Cl6 octahedra, corners with four equivalent Na(2)Cl6 octahedra, edges with two equivalent K(1)Cl6 octahedra, edges with four equivalent Na(1)Cl6 octahedra, and edges with six equivalent Na(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 3-5°. Both K(1)-Cl(1) bond lengths are 3.00 Å. All K(1)-Cl(2) bond lengths are 3.03 Å. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded to one Cl(2), two equivalent Cl(3), and three equivalent Cl(1) atoms to form NaCl6 octahedra that share  a cornercorner with one K(1)Cl6 octahedra, corners with two equivalent Na(1)Cl6 octahedra, corners with three equivalent Na(2)Cl6 octahedra, edges with two equivalent K(1)Cl6 octahedra, edges with five equivalent Na(1)Cl6 octahedra, and edges with five equivalent Na(2)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. The Na(1)-Cl(2) bond length is 2.86 Å. Both Na(1)-Cl(3) bond lengths are 2.83 Å. There is one shorter (2.77 Å) and two longer (2.88 Å) Na(1)-Cl(1) bond lengths. In the second Na site, Na(2) is bonded to one Cl(3), two equivalent Cl(1), and three equivalent Cl(2) atoms to form NaCl6 octahedra that share  a cornercorner with one Na(2)Cl6 octahedra, corners with two equivalent K(1)Cl6 octahedra, corners with three equivalent Na(1)Cl6 octahedra, edges with three equivalent K(1)Cl6 octahedra, edges with four equivalent Na(2)Cl6 octahedra, and edges with five equivalent Na(1)Cl6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. The Na(2)-Cl(3) bond length is 2.84 Å. Both Na(2)-Cl(1) bond lengths are 2.85 Å. There are two shorter (2.77 Å) and one longer (2.96 Å) Na(2)-Cl(2) bond length. There are three inequivalent Cl sites. In the first Cl site, Cl(1) is bonded to one K(1), two equivalent Na(2), and three equivalent Na(1) atoms to form ClKNa5 octahedra that share  a cornercorner with one Cl(1)KNa5 octahedra, corners with two equivalent Cl(3)Na6 octahedra, corners with three equivalent Cl(2)K2Na4 octahedra, edges with three equivalent Cl(3)Na6 octahedra, edges with four equivalent Cl(1)KNa5 octahedra, and edges with five equivalent Cl(2)K2Na4 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Cl site, Cl(2) is bonded to two equivalent K(1), one Na(1), and three equivalent Na(2) atoms to form ClK2Na4 octahedra that share  a cornercorner with one Cl(3)Na6 octahedra, corners with two equivalent Cl(2)K2Na4 octahedra, corners with three equivalent Cl(1)KNa5 octahedra, edges with two equivalent Cl(3)Na6 octahedra, edges with five equivalent Cl(2)K2Na4 octahedra, and edges with five equivalent Cl(1)KNa5 octahedra. The corner-sharing octahedral tilt angles range from 0-7°. In the third Cl site, Cl(3) is bonded to two equivalent Na(2) and four equivalent Na(1) atoms to form ClNa6 octahedra that share corners with two equivalent Cl(2)K2Na4 octahedra, corners with four equivalent Cl(1)KNa5 octahedra, edges with two equivalent Cl(3)Na6 octahedra, edges with four equivalent Cl(2)K2Na4 octahedra, and edges with six equivalent Cl(1)KNa5 octahedra. The corner-sharing octahedral tilt angles range from 3-7°.