SrCaMg6 crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Ca(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form SrCa2Mg10 cuboctahedra that share corners with four equivalent Ca(1)Sr2Mg10 cuboctahedra, corners with six equivalent Sr(1)Ca2Mg10 cuboctahedra, edges with two equivalent Ca(1)Sr2Mg10 cuboctahedra, faces with two equivalent Sr(1)Ca2Mg10 cuboctahedra, and faces with two equivalent Ca(1)Sr2Mg10 cuboctahedra. Ca(1) is bonded to two equivalent Sr(1), two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms to form CaSr2Mg10 cuboctahedra that share corners with four equivalent Sr(1)Ca2Mg10 cuboctahedra, corners with six equivalent Ca(1)Sr2Mg10 cuboctahedra, edges with two equivalent Sr(1)Ca2Mg10 cuboctahedra, faces with two equivalent Sr(1)Ca2Mg10 cuboctahedra, and faces with two equivalent Ca(1)Sr2Mg10 cuboctahedra. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Ca(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Sr(1), two equivalent Ca(1), one Mg(3), one Mg(4), and two equivalent Mg(1) atoms. In the third Mg site, Mg(3) is bonded in a 8-coordinate geometry to two equivalent Ca(1), two equivalent Mg(2), and four equivalent Mg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 8-coordinate geometry to two equivalent Sr(1), two equivalent Mg(2), and four equivalent Mg(1) atoms.
SrCaMg6 crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Ca(1), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(2) atoms to form SrCa2Mg10 cuboctahedra that share corners with four equivalent Ca(1)Sr2Mg10 cuboctahedra, corners with six equivalent Sr(1)Ca2Mg10 cuboctahedra, edges with two equivalent Ca(1)Sr2Mg10 cuboctahedra, faces with two equivalent Sr(1)Ca2Mg10 cuboctahedra, and faces with two equivalent Ca(1)Sr2Mg10 cuboctahedra. Both Sr(1)-Ca(1) bond lengths are 3.57 Å. Both Sr(1)-Mg(4) bond lengths are 3.45 Å. There are two shorter (3.43 Å) and two longer (3.50 Å) Sr(1)-Mg(1) bond lengths. All Sr(1)-Mg(2) bond lengths are 3.44 Å. Ca(1) is bonded to two equivalent Sr(1), two equivalent Mg(3), four equivalent Mg(1), and four equivalent Mg(2) atoms to form CaSr2Mg10 cuboctahedra that share corners with four equivalent Sr(1)Ca2Mg10 cuboctahedra, corners with six equivalent Ca(1)Sr2Mg10 cuboctahedra, edges with two equivalent Sr(1)Ca2Mg10 cuboctahedra, faces with two equivalent Sr(1)Ca2Mg10 cuboctahedra, and faces with two equivalent Ca(1)Sr2Mg10 cuboctahedra. Both Ca(1)-Mg(3) bond lengths are 3.43 Å. There are two shorter (3.41 Å) and two longer (3.52 Å) Ca(1)-Mg(1) bond lengths. All Ca(1)-Mg(2) bond lengths are 3.39 Å. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Ca(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. Both Mg(1)-Mg(2) bond lengths are 3.28 Å. Both Mg(1)-Mg(3) bond lengths are 3.38 Å. Both Mg(1)-Mg(4) bond lengths are 3.36 Å. In the second Mg site, Mg(2) is bonded in a 4-coordinate geometry to two equivalent Sr(1), two equivalent Ca(1), one Mg(3), one Mg(4), and two equivalent Mg(1) atoms. The Mg(2)-Mg(3) bond length is 3.32 Å. The Mg(2)-Mg(4) bond length is 3.23 Å. In the third Mg site, Mg(3) is bonded in a 8-coordinate geometry to two equivalent Ca(1), two equivalent Mg(2), and four equivalent Mg(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 8-coordinate geometry to two equivalent Sr(1), two equivalent Mg(2), and four equivalent Mg(1) atoms.