K2Zn5As4 is alpha Pu-derived structured and crystallizes in the orthorhombic Cmcm space group. K(1) is bonded in a 18-coordinate geometry to two equivalent K(1), two equivalent Zn(1), two equivalent Zn(3), four equivalent Zn(2), four equivalent As(1), and four equivalent As(2) atoms. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to two equivalent K(1), two equivalent As(1), and two equivalent As(2) atoms to form distorted ZnK2As4 tetrahedra that share corners with two equivalent Zn(2)K4As4 tetrahedra, corners with four equivalent Zn(1)K2As4 tetrahedra,  an edgeedge with one Zn(1)K2As4 tetrahedra, edges with four equivalent Zn(2)K4As4 tetrahedra, and faces with two equivalent Zn(2)K4As4 tetrahedra. In the second Zn site, Zn(2) is bonded to four equivalent K(1), two equivalent As(1), and two equivalent As(2) atoms to form distorted ZnK4As4 tetrahedra that share corners with two equivalent Zn(1)K2As4 tetrahedra, corners with four equivalent Zn(2)K4As4 tetrahedra, edges with four equivalent Zn(1)K2As4 tetrahedra, edges with four equivalent Zn(2)K4As4 tetrahedra,  a faceface with one Zn(2)K4As4 tetrahedra, and faces with two equivalent Zn(1)K2As4 tetrahedra. In the third Zn site, Zn(3) is bonded in a 4-coordinate geometry to four equivalent K(1), two equivalent As(1), and two equivalent As(2) atoms. There are two inequivalent As sites. In the first As site, As(2) is bonded in a 7-coordinate geometry to four equivalent K(1), one Zn(3), two equivalent Zn(1), and two equivalent Zn(2) atoms. In the second As site, As(1) is bonded in a 5-coordinate geometry to four equivalent K(1), one Zn(3), two equivalent Zn(1), and two equivalent Zn(2) atoms.
K2Zn5As4 is alpha Pu-derived structured and crystallizes in the orthorhombic Cmcm space group. K(1) is bonded in a 18-coordinate geometry to two equivalent K(1), two equivalent Zn(1), two equivalent Zn(3), four equivalent Zn(2), four equivalent As(1), and four equivalent As(2) atoms. Both K(1)-K(1) bond lengths are 3.68 Å. Both K(1)-Zn(1) bond lengths are 3.48 Å. Both K(1)-Zn(3) bond lengths are 3.87 Å. There are two shorter (3.75 Å) and two longer (3.76 Å) K(1)-Zn(2) bond lengths. There are two shorter (3.48 Å) and two longer (3.79 Å) K(1)-As(1) bond lengths. There are two shorter (3.40 Å) and two longer (3.89 Å) K(1)-As(2) bond lengths. There are three inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to two equivalent K(1), two equivalent As(1), and two equivalent As(2) atoms to form distorted ZnK2As4 tetrahedra that share corners with two equivalent Zn(2)K4As4 tetrahedra, corners with four equivalent Zn(1)K2As4 tetrahedra,  an edgeedge with one Zn(1)K2As4 tetrahedra, edges with four equivalent Zn(2)K4As4 tetrahedra, and faces with two equivalent Zn(2)K4As4 tetrahedra. There is one shorter (2.51 Å) and one longer (2.67 Å) Zn(1)-As(1) bond length. Both Zn(1)-As(2) bond lengths are 2.57 Å. In the second Zn site, Zn(2) is bonded to four equivalent K(1), two equivalent As(1), and two equivalent As(2) atoms to form distorted ZnK4As4 tetrahedra that share corners with two equivalent Zn(1)K2As4 tetrahedra, corners with four equivalent Zn(2)K4As4 tetrahedra, edges with four equivalent Zn(1)K2As4 tetrahedra, edges with four equivalent Zn(2)K4As4 tetrahedra,  a faceface with one Zn(2)K4As4 tetrahedra, and faces with two equivalent Zn(1)K2As4 tetrahedra. Both Zn(2)-As(1) bond lengths are 2.60 Å. There is one shorter (2.49 Å) and one longer (2.70 Å) Zn(2)-As(2) bond length. In the third Zn site, Zn(3) is bonded in a 4-coordinate geometry to four equivalent K(1), two equivalent As(1), and two equivalent As(2) atoms. Both Zn(3)-As(1) bond lengths are 2.57 Å. Both Zn(3)-As(2) bond lengths are 2.63 Å. There are two inequivalent As sites. In the first As site, As(2) is bonded in a 7-coordinate geometry to four equivalent K(1), one Zn(3), two equivalent Zn(1), and two equivalent Zn(2) atoms. In the second As site, As(1) is bonded in a 5-coordinate geometry to four equivalent K(1), one Zn(3), two equivalent Zn(1), and two equivalent Zn(2) atoms.