CaSm(FeO3)4 crystallizes in the orthorhombic Cmmm space group. Ca(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Sm(1)O12 cuboctahedra, and faces with eight equivalent Fe(1)O6 octahedra. Sm(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms to form SmO12 cuboctahedra that share corners with four equivalent Sm(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Fe(1)O6 octahedra. Fe(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra, faces with two equivalent Ca(1)O12 cuboctahedra, and faces with two equivalent Sm(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ca(1), one Sm(1), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Ca(1), one Sm(1), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a distorted square co-planar geometry to two equivalent Ca(1) and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to two equivalent Sm(1) and two equivalent Fe(1) atoms.
CaSm(FeO3)4 crystallizes in the orthorhombic Cmmm space group. Ca(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(3) atoms to form CaO12 cuboctahedra that share corners with four equivalent Ca(1)O12 cuboctahedra, corners with eight equivalent Sm(1)O12 cuboctahedra, and faces with eight equivalent Fe(1)O6 octahedra. All Ca(1)-O(1) bond lengths are 2.78 Å. All Ca(1)-O(2) bond lengths are 2.73 Å. All Ca(1)-O(3) bond lengths are 2.68 Å. Sm(1) is bonded to four equivalent O(1), four equivalent O(2), and four equivalent O(4) atoms to form SmO12 cuboctahedra that share corners with four equivalent Sm(1)O12 cuboctahedra, corners with eight equivalent Ca(1)O12 cuboctahedra, and faces with eight equivalent Fe(1)O6 octahedra. All Sm(1)-O(1) bond lengths are 2.60 Å. All Sm(1)-O(2) bond lengths are 2.65 Å. All Sm(1)-O(4) bond lengths are 2.68 Å. Fe(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O6 octahedra, faces with two equivalent Ca(1)O12 cuboctahedra, and faces with two equivalent Sm(1)O12 cuboctahedra. The corner-sharing octahedral tilt angles range from 0-6°. The Fe(1)-O(3) bond length is 1.89 Å. The Fe(1)-O(4) bond length is 1.93 Å. Both Fe(1)-O(1) bond lengths are 1.90 Å. Both Fe(1)-O(2) bond lengths are 1.90 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to one Ca(1), one Sm(1), and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a distorted linear geometry to one Ca(1), one Sm(1), and two equivalent Fe(1) atoms. In the third O site, O(3) is bonded in a distorted square co-planar geometry to two equivalent Ca(1) and two equivalent Fe(1) atoms. In the fourth O site, O(4) is bonded in a distorted linear geometry to two equivalent Sm(1) and two equivalent Fe(1) atoms.