CaPbSe2 crystallizes in the tetragonal P4/mmm space group. Ca(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CaSe6 octahedra that share corners with six equivalent Ca(1)Se6 octahedra, edges with four equivalent Ca(1)Se6 octahedra, and edges with eight equivalent Pb(1)Se6 octahedra. The corner-sharing octahedra are not tilted. Pb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form PbSe6 octahedra that share corners with six equivalent Pb(1)Se6 octahedra, edges with four equivalent Pb(1)Se6 octahedra, and edges with eight equivalent Ca(1)Se6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ca(1) and four equivalent Pb(1) atoms to form SeCa2Pb4 octahedra that share corners with six equivalent Se(1)Ca2Pb4 octahedra, edges with four equivalent Se(1)Ca2Pb4 octahedra, and edges with eight equivalent Se(2)Ca4Pb2 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to four equivalent Ca(1) and two equivalent Pb(1) atoms to form SeCa4Pb2 octahedra that share corners with six equivalent Se(2)Ca4Pb2 octahedra, edges with four equivalent Se(2)Ca4Pb2 octahedra, and edges with eight equivalent Se(1)Ca2Pb4 octahedra. The corner-sharing octahedra are not tilted.
CaPbSe2 crystallizes in the tetragonal P4/mmm space group. Ca(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form CaSe6 octahedra that share corners with six equivalent Ca(1)Se6 octahedra, edges with four equivalent Ca(1)Se6 octahedra, and edges with eight equivalent Pb(1)Se6 octahedra. The corner-sharing octahedra are not tilted. Both Ca(1)-Se(1) bond lengths are 3.04 Å. All Ca(1)-Se(2) bond lengths are 3.03 Å. Pb(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form PbSe6 octahedra that share corners with six equivalent Pb(1)Se6 octahedra, edges with four equivalent Pb(1)Se6 octahedra, and edges with eight equivalent Ca(1)Se6 octahedra. The corner-sharing octahedra are not tilted. Both Pb(1)-Se(2) bond lengths are 3.04 Å. All Pb(1)-Se(1) bond lengths are 3.03 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Ca(1) and four equivalent Pb(1) atoms to form SeCa2Pb4 octahedra that share corners with six equivalent Se(1)Ca2Pb4 octahedra, edges with four equivalent Se(1)Ca2Pb4 octahedra, and edges with eight equivalent Se(2)Ca4Pb2 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to four equivalent Ca(1) and two equivalent Pb(1) atoms to form SeCa4Pb2 octahedra that share corners with six equivalent Se(2)Ca4Pb2 octahedra, edges with four equivalent Se(2)Ca4Pb2 octahedra, and edges with eight equivalent Se(1)Ca2Pb4 octahedra. The corner-sharing octahedra are not tilted.