K3BiAs6Se12 crystallizes in the trigonal P-3 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent Se(1) atoms to form distorted KSe6 octahedra that share faces with two equivalent Bi(1)Se6 octahedra. In the second K site, K(2) is bonded in a distorted q6 geometry to three equivalent Se(1) and six equivalent Se(2) atoms. Bi(1) is bonded to six equivalent Se(1) atoms to form BiSe6 octahedra that share faces with two equivalent K(1)Se6 octahedra. As(1) is bonded in a trigonal non-coplanar geometry to one Se(1) and two equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Bi(1), and one As(1) atom. In the second Se site, Se(2) is bonded to two equivalent K(2) and two equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing SeK2As2 trigonal pyramids.
K3BiAs6Se12 crystallizes in the trigonal P-3 space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to six equivalent Se(1) atoms to form distorted KSe6 octahedra that share faces with two equivalent Bi(1)Se6 octahedra. All K(1)-Se(1) bond lengths are 3.37 Å. In the second K site, K(2) is bonded in a distorted q6 geometry to three equivalent Se(1) and six equivalent Se(2) atoms. All K(2)-Se(1) bond lengths are 3.56 Å. There are three shorter (3.64 Å) and three longer (3.76 Å) K(2)-Se(2) bond lengths. Bi(1) is bonded to six equivalent Se(1) atoms to form BiSe6 octahedra that share faces with two equivalent K(1)Se6 octahedra. All Bi(1)-Se(1) bond lengths are 3.01 Å. As(1) is bonded in a trigonal non-coplanar geometry to one Se(1) and two equivalent Se(2) atoms. The As(1)-Se(1) bond length is 2.38 Å. There is one shorter (2.47 Å) and one longer (2.49 Å) As(1)-Se(2) bond length. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 4-coordinate geometry to one K(1), one K(2), one Bi(1), and one As(1) atom. In the second Se site, Se(2) is bonded to two equivalent K(2) and two equivalent As(1) atoms to form a mixture of distorted corner and edge-sharing SeK2As2 trigonal pyramids.