SrMg6Y is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(2), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted SrMg12 cuboctahedra that share corners with four equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, corners with six equivalent Sr(1)Mg12 cuboctahedra, edges with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, and faces with six equivalent Y(1)Mg12 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), one Mg(1), one Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Y(1) atoms. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Y(1) atoms. In the fourth Mg site, Mg(4) is bonded to two equivalent Sr(1), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms to form distorted MgSr2Y2Mg8 cuboctahedra that share corners with four equivalent Sr(1)Mg12 cuboctahedra, corners with six equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, edges with two equivalent Sr(1)Mg12 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, and faces with two equivalent Y(1)Mg12 cuboctahedra. Y(1) is bonded to two equivalent Mg(2), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form YMg12 cuboctahedra that share corners with six equivalent Y(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, faces with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with six equivalent Sr(1)Mg12 cuboctahedra.
SrMg6Y is Bergman Structure: Mg32(Al,Zn)49 Bergman-like structured and crystallizes in the orthorhombic Amm2 space group. Sr(1) is bonded to two equivalent Mg(2), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form distorted SrMg12 cuboctahedra that share corners with four equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, corners with six equivalent Sr(1)Mg12 cuboctahedra, edges with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, and faces with six equivalent Y(1)Mg12 cuboctahedra. Both Sr(1)-Mg(2) bond lengths are 3.46 Å. Both Sr(1)-Mg(4) bond lengths are 3.55 Å. All Sr(1)-Mg(1) bond lengths are 3.38 Å. There are two shorter (3.41 Å) and two longer (3.43 Å) Sr(1)-Mg(3) bond lengths. 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), one Mg(1), one Mg(2), two equivalent Mg(3), two equivalent Mg(4), and two equivalent Y(1) atoms. The Mg(1)-Mg(1) bond length is 3.15 Å. The Mg(1)-Mg(2) bond length is 3.23 Å. Both Mg(1)-Mg(3) bond lengths are 3.34 Å. Both Mg(1)-Mg(4) bond lengths are 3.21 Å. Both Mg(1)-Y(1) bond lengths are 3.43 Å. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Sr(1), two equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms. All Mg(2)-Mg(3) bond lengths are 3.19 Å. Both Mg(2)-Y(1) bond lengths are 3.55 Å. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to two equivalent Sr(1), one Mg(3), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), and two equivalent Y(1) atoms. The Mg(3)-Mg(3) bond length is 3.28 Å. Both Mg(3)-Mg(4) bond lengths are 3.42 Å. Both Mg(3)-Y(1) bond lengths are 3.33 Å. In the fourth Mg site, Mg(4) is bonded to two equivalent Sr(1), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Y(1) atoms to form distorted MgSr2Y2Mg8 cuboctahedra that share corners with four equivalent Sr(1)Mg12 cuboctahedra, corners with six equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, edges with two equivalent Sr(1)Mg12 cuboctahedra, edges with four equivalent Y(1)Mg12 cuboctahedra, faces with two equivalent Sr(1)Mg12 cuboctahedra, faces with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, and faces with two equivalent Y(1)Mg12 cuboctahedra. Both Mg(4)-Y(1) bond lengths are 3.36 Å. Y(1) is bonded to two equivalent Mg(2), two equivalent Mg(4), four equivalent Mg(1), and four equivalent Mg(3) atoms to form YMg12 cuboctahedra that share corners with six equivalent Y(1)Mg12 cuboctahedra, edges with four equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, faces with two equivalent Mg(4)Sr2Y2Mg8 cuboctahedra, faces with two equivalent Y(1)Mg12 cuboctahedra, and faces with six equivalent Sr(1)Mg12 cuboctahedra.