CaMnO2 is Caswellsilverite-like structured and crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(4) atoms to form CaO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with three equivalent Ca(2)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with three equivalent Ca(1)O6 octahedra, edges with three equivalent Mn(2)O6 octahedra, and edges with four equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, edges with two equivalent Ca(2)O6 octahedra, edges with three equivalent Ca(1)O6 octahedra, edges with three equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-4°. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(2), and three equivalent O(1) atoms to form MnO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, edges with two equivalent Ca(1)O6 octahedra, edges with three equivalent Ca(2)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), two equivalent Mn(1), and three equivalent Mn(2) atoms to form OCaMn5 octahedra that share corners with two equivalent O(2)Ca3Mn3 octahedra, corners with two equivalent O(3)Ca3Mn3 octahedra, corners with two equivalent O(4)Ca5Mn octahedra, edges with two equivalent O(4)Ca5Mn octahedra, edges with three equivalent O(2)Ca3Mn3 octahedra, edges with three equivalent O(3)Ca3Mn3 octahedra, and edges with four equivalent O(1)CaMn5 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded to three equivalent Ca(2), one Mn(1), and two equivalent Mn(2) atoms to form OCa3Mn3 octahedra that share corners with two equivalent O(3)Ca3Mn3 octahedra, corners with two equivalent O(4)Ca5Mn octahedra, corners with two equivalent O(1)CaMn5 octahedra, edges with two equivalent O(3)Ca3Mn3 octahedra, edges with three equivalent O(4)Ca5Mn octahedra, edges with three equivalent O(1)CaMn5 octahedra, and edges with four equivalent O(2)Ca3Mn3 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and three equivalent Mn(1) atoms to form OCa3Mn3 octahedra that share corners with two equivalent O(2)Ca3Mn3 octahedra, corners with two equivalent O(4)Ca5Mn octahedra, corners with two equivalent O(1)CaMn5 octahedra, edges with two equivalent O(2)Ca3Mn3 octahedra, edges with three equivalent O(4)Ca5Mn octahedra, edges with three equivalent O(1)CaMn5 octahedra, and edges with four equivalent O(3)Ca3Mn3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the fourth O site, O(4) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Mn(2) atom to form OCa5Mn octahedra that share corners with two equivalent O(2)Ca3Mn3 octahedra, corners with two equivalent O(3)Ca3Mn3 octahedra, corners with two equivalent O(1)CaMn5 octahedra, edges with two equivalent O(1)CaMn5 octahedra, edges with three equivalent O(2)Ca3Mn3 octahedra, edges with three equivalent O(3)Ca3Mn3 octahedra, and edges with four equivalent O(4)Ca5Mn octahedra. The corner-sharing octahedral tilt angles range from 1-2°.
CaMnO2 is Caswellsilverite-like structured and crystallizes in the monoclinic P2_1/m space group. There are two inequivalent Ca sites. In the first Ca site, Ca(1) is bonded to one O(1), two equivalent O(3), and three equivalent O(4) atoms to form CaO6 octahedra that share corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with three equivalent Ca(2)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with four equivalent Ca(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. The Ca(1)-O(1) bond length is 2.32 Å. Both Ca(1)-O(3) bond lengths are 2.38 Å. There are two shorter (2.36 Å) and one longer (2.45 Å) Ca(1)-O(4) bond length. In the second Ca site, Ca(2) is bonded to one O(3), two equivalent O(4), and three equivalent O(2) atoms to form CaO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with three equivalent Ca(1)O6 octahedra, edges with three equivalent Mn(2)O6 octahedra, and edges with four equivalent Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. The Ca(2)-O(3) bond length is 2.38 Å. Both Ca(2)-O(4) bond lengths are 2.36 Å. There are two shorter (2.38 Å) and one longer (2.39 Å) Ca(2)-O(2) bond length. There are two inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to one O(2), two equivalent O(1), and three equivalent O(3) atoms to form MnO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Mn(2)O6 octahedra, edges with two equivalent Ca(2)O6 octahedra, edges with three equivalent Ca(1)O6 octahedra, edges with three equivalent Mn(2)O6 octahedra, and edges with four equivalent Mn(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 2-4°. The Mn(1)-O(2) bond length is 2.27 Å. Both Mn(1)-O(1) bond lengths are 2.33 Å. There is one shorter (2.28 Å) and two longer (2.29 Å) Mn(1)-O(3) bond lengths. In the second Mn site, Mn(2) is bonded to one O(4), two equivalent O(2), and three equivalent O(1) atoms to form MnO6 octahedra that share corners with two equivalent Ca(1)O6 octahedra, corners with two equivalent Ca(2)O6 octahedra, corners with two equivalent Mn(1)O6 octahedra, edges with two equivalent Ca(1)O6 octahedra, edges with three equivalent Ca(2)O6 octahedra, edges with three equivalent Mn(1)O6 octahedra, and edges with four equivalent Mn(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. The Mn(2)-O(4) bond length is 2.33 Å. Both Mn(2)-O(2) bond lengths are 2.30 Å. There is one shorter (2.21 Å) and two longer (2.34 Å) Mn(2)-O(1) bond lengths. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Ca(1), two equivalent Mn(1), and three equivalent Mn(2) atoms to form OCaMn5 octahedra that share corners with two equivalent O(2)Ca3Mn3 octahedra, corners with two equivalent O(3)Ca3Mn3 octahedra, corners with two equivalent O(4)Ca5Mn octahedra, edges with two equivalent O(4)Ca5Mn octahedra, edges with three equivalent O(2)Ca3Mn3 octahedra, edges with three equivalent O(3)Ca3Mn3 octahedra, and edges with four equivalent O(1)CaMn5 octahedra. The corner-sharing octahedral tilt angles are 1°. In the second O site, O(2) is bonded to three equivalent Ca(2), one Mn(1), and two equivalent Mn(2) atoms to form OCa3Mn3 octahedra that share corners with two equivalent O(3)Ca3Mn3 octahedra, corners with two equivalent O(4)Ca5Mn octahedra, corners with two equivalent O(1)CaMn5 octahedra, edges with two equivalent O(3)Ca3Mn3 octahedra, edges with three equivalent O(4)Ca5Mn octahedra, edges with three equivalent O(1)CaMn5 octahedra, and edges with four equivalent O(2)Ca3Mn3 octahedra. The corner-sharing octahedral tilt angles are 1°. In the third O site, O(3) is bonded to one Ca(2), two equivalent Ca(1), and three equivalent Mn(1) atoms to form OCa3Mn3 octahedra that share corners with two equivalent O(2)Ca3Mn3 octahedra, corners with two equivalent O(4)Ca5Mn octahedra, corners with two equivalent O(1)CaMn5 octahedra, edges with two equivalent O(2)Ca3Mn3 octahedra, edges with three equivalent O(4)Ca5Mn octahedra, edges with three equivalent O(1)CaMn5 octahedra, and edges with four equivalent O(3)Ca3Mn3 octahedra. The corner-sharing octahedral tilt angles range from 1-2°. In the fourth O site, O(4) is bonded to two equivalent Ca(2), three equivalent Ca(1), and one Mn(2) atom to form OCa5Mn octahedra that share corners with two equivalent O(2)Ca3Mn3 octahedra, corners with two equivalent O(3)Ca3Mn3 octahedra, corners with two equivalent O(1)CaMn5 octahedra, edges with two equivalent O(1)CaMn5 octahedra, edges with three equivalent O(2)Ca3Mn3 octahedra, edges with three equivalent O(3)Ca3Mn3 octahedra, and edges with four equivalent O(4)Ca5Mn octahedra. The corner-sharing octahedral tilt angles range from 1-2°.