Materials Data on CaMgCd by Materials Project
CaMgCd crystallizes in the orthorhombic Amm2 space group. The structure is three-dimensional. there are two inequivalent Ca sites. In the first Ca site, Ca is bonded in a 12-coordinate geometry to four Ca, five Mg, and seven Cd atoms. There are a spread of Ca–Ca bond distances ranging from 3.66–3.78 Å. There are a spread of Ca–Mg bond distances ranging from 3.58–3.61 Å. There are a spread of Ca–Cd bond distances ranging from 3.53–3.57 Å. In the second Ca site, Ca is bonded in a 12-coordinate geometry to three equivalent Ca, seven Mg, and five Cd atoms. There are a spread of Ca–Mg bond distances ranging from 3.55–3.62 Å. There are a spread of Ca–Cd bond distances ranging from 3.49–3.54 Å. There are three inequivalent Mg sites. In the first Mg site, Mg is bonded to six Ca and six Cd atoms to form distorted MgCa6Cd6 cuboctahedra that share corners with four equivalent CdCa6Mg4Cd2 cuboctahedra, corners with fourteen MgCa6Cd6 cuboctahedra, edges with six MgCa6Cd6 cuboctahedra, faces with four equivalent MgCa6Mg4Cd2 cuboctahedra, and faces with fourteen CdCa6Mg4Cd2 cuboctahedra. There are a spread of Mg–Cd bond distances ranging from 2.98–3.06 Å. In the second Mg site, Mg is bonded to six Ca, four Mg, and two equivalent Cd atoms to form distorted MgCa6Mg4Cd2 cuboctahedra that share corners with eight MgCa6Cd6 cuboctahedra, corners with ten CdCa6Mg4Cd2 cuboctahedra, edges with two equivalent MgCa6Mg4Cd2 cuboctahedra, edges with four equivalent CdCa6Mg2Cd4 cuboctahedra, faces with eight CdCa6Mg4Cd2 cuboctahedra, and faces with ten MgCa6Cd6 cuboctahedra. There are a spread of Mg–Mg bond distances ranging from 2.98–3.06 Å. Both Mg–Cd bond lengths are 3.06 Å. In the third Mg site, Mg is bonded to six Ca, four equivalent Mg, and two equivalent Cd atoms to form distorted MgCa6Mg4Cd2 cuboctahedra that share corners with six MgCa6Cd6 cuboctahedra, corners with twelve CdCa6Mg4Cd2 cuboctahedra, edges with six MgCa6Cd6 cuboctahedra, faces with eight equivalent MgCa6Mg4Cd2 cuboctahedra, and faces with ten CdCa6Mg4Cd2 cuboctahedra. Both Mg–Cd bond lengths are 3.06 Å. There are two inequivalent Cd sites. In the first Cd site, Cd is bonded to six Ca, four Mg, and two equivalent Cd atoms to form distorted CdCa6Mg4Cd2 cuboctahedra that share corners with four equivalent CdCa6Mg2Cd4 cuboctahedra, corners with eight MgCa6Cd6 cuboctahedra, edges with six equivalent CdCa6Mg4Cd2 cuboctahedra, faces with eight CdCa6Mg4Cd2 cuboctahedra, and faces with twelve MgCa6Cd6 cuboctahedra. Both Cd–Cd bond lengths are 3.12 Å. In the second Cd site, Cd is bonded to six Ca, two equivalent Mg, and four Cd atoms to form distorted CdCa6Mg2Cd4 cuboctahedra that share corners with eight CdCa6Mg4Cd2 cuboctahedra, corners with ten MgCa6Mg4Cd2 cuboctahedra, edges with two equivalent CdCa6Mg2Cd4 cuboctahedra, edges with four equivalent MgCa6Mg4Cd2 cuboctahedra, faces with eight MgCa6Cd6 cuboctahedra, and faces with ten CdCa6Mg4Cd2 cuboctahedra. There are one shorter (2.97 Å) and one longer (3.10 Å) Cd–Cd bond lengths.