K3SmN6 is Ilmenite-like structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to two equivalent N(1) and four equivalent N(2) atoms. In the second K site, K(2) is bonded to two equivalent N(1) and four equivalent N(2) atoms to form distorted KN6 octahedra that share corners with two equivalent Sm(1)N6 octahedra, edges with two equivalent Sm(1)N6 octahedra, and edges with three equivalent K(2)N6 octahedra. The corner-sharing octahedral tilt angles are 6°. Sm(1) is bonded to two equivalent N(1) and four equivalent N(2) atoms to form SmN6 octahedra that share corners with four equivalent K(2)N6 octahedra and edges with four equivalent K(2)N6 octahedra. The corner-sharing octahedral tilt angles are 6°. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted see-saw-like geometry to one K(1), two equivalent K(2), and one Sm(1) atom. In the second N site, N(2) is bonded in a distorted see-saw-like geometry to one K(1), two equivalent K(2), and one Sm(1) atom.
K3SmN6 is Ilmenite-like structured and crystallizes in the monoclinic C2/m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded in a 6-coordinate geometry to two equivalent N(1) and four equivalent N(2) atoms. Both K(1)-N(1) bond lengths are 3.35 Å. All K(1)-N(2) bond lengths are 2.76 Å. In the second K site, K(2) is bonded to two equivalent N(1) and four equivalent N(2) atoms to form distorted KN6 octahedra that share corners with two equivalent Sm(1)N6 octahedra, edges with two equivalent Sm(1)N6 octahedra, and edges with three equivalent K(2)N6 octahedra. The corner-sharing octahedral tilt angles are 6°. Both K(2)-N(1) bond lengths are 2.99 Å. There are two shorter (2.79 Å) and two longer (3.08 Å) K(2)-N(2) bond lengths. Sm(1) is bonded to two equivalent N(1) and four equivalent N(2) atoms to form SmN6 octahedra that share corners with four equivalent K(2)N6 octahedra and edges with four equivalent K(2)N6 octahedra. The corner-sharing octahedral tilt angles are 6°. Both Sm(1)-N(1) bond lengths are 2.38 Å. All Sm(1)-N(2) bond lengths are 2.35 Å. There are two inequivalent N sites. In the first N site, N(1) is bonded in a distorted see-saw-like geometry to one K(1), two equivalent K(2), and one Sm(1) atom. In the second N site, N(2) is bonded in a distorted see-saw-like geometry to one K(1), two equivalent K(2), and one Sm(1) atom.