KSm3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. K(1) is bonded to four equivalent Sm(2) and eight equivalent Sm(1) atoms to form KSm12 cuboctahedra that share corners with four equivalent K(1)Sm12 cuboctahedra, corners with eight equivalent Sm(2)K4Sm8 cuboctahedra, edges with eight equivalent K(1)Sm12 cuboctahedra, edges with sixteen equivalent Sm(1)K4Sm8 cuboctahedra, faces with four equivalent K(1)Sm12 cuboctahedra, faces with six equivalent Sm(2)K4Sm8 cuboctahedra, and faces with eight equivalent Sm(1)K4Sm8 cuboctahedra. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to four equivalent K(1), four equivalent Sm(1), and four equivalent Sm(2) atoms to form SmK4Sm8 cuboctahedra that share corners with twelve equivalent Sm(1)K4Sm8 cuboctahedra, edges with eight equivalent K(1)Sm12 cuboctahedra, edges with eight equivalent Sm(1)K4Sm8 cuboctahedra, edges with eight equivalent Sm(2)K4Sm8 cuboctahedra, faces with four equivalent K(1)Sm12 cuboctahedra, faces with four equivalent Sm(2)K4Sm8 cuboctahedra, and faces with ten equivalent Sm(1)K4Sm8 cuboctahedra. In the second Sm site, Sm(2) is bonded to four equivalent K(1) and eight equivalent Sm(1) atoms to form distorted SmK4Sm8 cuboctahedra that share corners with four equivalent Sm(2)K4Sm8 cuboctahedra, corners with eight equivalent K(1)Sm12 cuboctahedra, edges with eight equivalent Sm(2)K4Sm8 cuboctahedra, edges with sixteen equivalent Sm(1)K4Sm8 cuboctahedra, faces with four equivalent Sm(2)K4Sm8 cuboctahedra, faces with six equivalent K(1)Sm12 cuboctahedra, and faces with eight equivalent Sm(1)K4Sm8 cuboctahedra.
KSm3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. K(1) is bonded to four equivalent Sm(2) and eight equivalent Sm(1) atoms to form KSm12 cuboctahedra that share corners with four equivalent K(1)Sm12 cuboctahedra, corners with eight equivalent Sm(2)K4Sm8 cuboctahedra, edges with eight equivalent K(1)Sm12 cuboctahedra, edges with sixteen equivalent Sm(1)K4Sm8 cuboctahedra, faces with four equivalent K(1)Sm12 cuboctahedra, faces with six equivalent Sm(2)K4Sm8 cuboctahedra, and faces with eight equivalent Sm(1)K4Sm8 cuboctahedra. All K(1)-Sm(2) bond lengths are 3.74 Å. All K(1)-Sm(1) bond lengths are 3.80 Å. There are two inequivalent Sm sites. In the first Sm site, Sm(1) is bonded to four equivalent K(1), four equivalent Sm(1), and four equivalent Sm(2) atoms to form SmK4Sm8 cuboctahedra that share corners with twelve equivalent Sm(1)K4Sm8 cuboctahedra, edges with eight equivalent K(1)Sm12 cuboctahedra, edges with eight equivalent Sm(1)K4Sm8 cuboctahedra, edges with eight equivalent Sm(2)K4Sm8 cuboctahedra, faces with four equivalent K(1)Sm12 cuboctahedra, faces with four equivalent Sm(2)K4Sm8 cuboctahedra, and faces with ten equivalent Sm(1)K4Sm8 cuboctahedra. All Sm(1)-Sm(1) bond lengths are 3.74 Å. All Sm(1)-Sm(2) bond lengths are 3.80 Å. In the second Sm site, Sm(2) is bonded to four equivalent K(1) and eight equivalent Sm(1) atoms to form distorted SmK4Sm8 cuboctahedra that share corners with four equivalent Sm(2)K4Sm8 cuboctahedra, corners with eight equivalent K(1)Sm12 cuboctahedra, edges with eight equivalent Sm(2)K4Sm8 cuboctahedra, edges with sixteen equivalent Sm(1)K4Sm8 cuboctahedra, faces with four equivalent Sm(2)K4Sm8 cuboctahedra, faces with six equivalent K(1)Sm12 cuboctahedra, and faces with eight equivalent Sm(1)K4Sm8 cuboctahedra.