K6MnSe4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to one Se(1) and three equivalent Se(2) atoms. In the second K site, K(2) is bonded in a 5-coordinate geometry to one Se(1) and four equivalent Se(2) atoms. Mn(1) is bonded in a tetrahedral geometry to one Se(1) and three equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to three equivalent K(1), three equivalent K(2), and one Mn(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to three equivalent K(1), four equivalent K(2), and one Mn(1) atom.
K6MnSe4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 4-coordinate geometry to one Se(1) and three equivalent Se(2) atoms. The K(1)-Se(1) bond length is 3.32 Å. All K(1)-Se(2) bond lengths are 3.24 Å. In the second K site, K(2) is bonded in a 5-coordinate geometry to one Se(1) and four equivalent Se(2) atoms. The K(2)-Se(1) bond length is 3.39 Å. There are two shorter (3.34 Å) and two longer (3.53 Å) K(2)-Se(2) bond lengths. Mn(1) is bonded in a tetrahedral geometry to one Se(1) and three equivalent Se(2) atoms. The Mn(1)-Se(1) bond length is 2.59 Å. All Mn(1)-Se(2) bond lengths are 2.59 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 7-coordinate geometry to three equivalent K(1), three equivalent K(2), and one Mn(1) atom. In the second Se site, Se(2) is bonded in a 8-coordinate geometry to three equivalent K(1), four equivalent K(2), and one Mn(1) atom.