KMg14Cr crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent Mg(6); four Mg(3,3); four Mg(5,5); and two equivalent Cr(1) atoms to form KMg10Cr2 cuboctahedra that share corners with four equivalent Mg(2)Mg12 cuboctahedra; corners with six equivalent K(1)Mg10Cr2 cuboctahedra; corners with eight equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(1)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with six equivalent Mg(7)Mg11Cr cuboctahedra. There are nine inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2); two equivalent Mg(6); four equivalent Mg(4); and four Mg(5,5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Cr(1)K2Mg10 cuboctahedra; corners with six equivalent Mg(1)Mg12 cuboctahedra; corners with eight Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(2)Mg12 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; faces with four equivalent Mg(4)Mg12 cuboctahedra; and faces with six equivalent Mg(7)Mg11Cr cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1); two equivalent Mg(7); four equivalent Mg(4); and four Mg(5,5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent K(1)Mg10Cr2 cuboctahedra; corners with six equivalent Mg(2)Mg12 cuboctahedra; corners with eight Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(1)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; faces with four equivalent Mg(4)Mg12 cuboctahedra; and faces with six equivalent Mg(6)KMg11 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Mg(3), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and two equivalent Cr(1) atoms to form distorted MgK2Mg8Cr2 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra; corners with four equivalent Mg(2)Mg12 cuboctahedra; corners with four equivalent Mg(4)Mg12 cuboctahedra; corners with six Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(5)KMg10Cr cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; and faces with eight Mg(5,5)KMg10Cr cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with four equivalent K(1)Mg10Cr2 cuboctahedra; corners with four equivalent Mg(3)K2Mg8Cr2 cuboctahedra; corners with four equivalent Cr(1)K2Mg10 cuboctahedra; corners with six equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Mg(4)Mg12 cuboctahedra; edges with four equivalent Mg(5)KMg10Cr cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(1)Mg12 cuboctahedra; faces with two equivalent Mg(2)Mg12 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; and faces with eight Mg(5,5)KMg10Cr cuboctahedra. In the fifth Mg site, Mg(3) is bonded to two equivalent K(1); two equivalent Mg(3); two Mg(5,5); two equivalent Mg(6); two equivalent Mg(7); and two equivalent Cr(1) atoms to form distorted MgK2Mg8Cr2 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra; corners with four equivalent Mg(2)Mg12 cuboctahedra; corners with four equivalent Mg(4)Mg12 cuboctahedra; corners with six Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four Mg(5,5)KMg10Cr cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; and faces with eight Mg(5,5)KMg10Cr cuboctahedra. In the sixth Mg site, Mg(5) is bonded to one K(1), one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and one Cr(1) atom to form distorted MgKMg10Cr cuboctahedra that share corners with four equivalent Mg(6)KMg11 cuboctahedra; corners with four equivalent Mg(7)Mg11Cr cuboctahedra; corners with ten Mg(5,5)KMg10Cr cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(5)KMg10Cr cuboctahedra; edges with two equivalent Mg(6)KMg11 cuboctahedra; edges with two equivalent Mg(7)Mg11Cr cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra;  a faceface with one K(1)Mg10Cr2 cuboctahedra;  a faceface with one Mg(1)Mg12 cuboctahedra;  a faceface with one Mg(2)Mg12 cuboctahedra;  a faceface with one Cr(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with four equivalent Mg(4)Mg12 cuboctahedra. In the seventh Mg site, Mg(5) is bonded to one K(1), one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and one Cr(1) atom to form distorted MgKMg10Cr cuboctahedra that share corners with four equivalent Mg(6)KMg11 cuboctahedra; corners with four equivalent Mg(7)Mg11Cr cuboctahedra; corners with ten equivalent Mg(5)KMg10Cr cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(5)KMg10Cr cuboctahedra; edges with two equivalent Mg(6)KMg11 cuboctahedra; edges with two equivalent Mg(7)Mg11Cr cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra;  a faceface with one K(1)Mg10Cr2 cuboctahedra;  a faceface with one Mg(1)Mg12 cuboctahedra;  a faceface with one Mg(2)Mg12 cuboctahedra;  a faceface with one Cr(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with four equivalent Mg(4)Mg12 cuboctahedra. In the eighth Mg site, Mg(6) is bonded to one K(1); one Mg(1); two equivalent Mg(3); two equivalent Mg(4); two equivalent Mg(7); and four Mg(5,5) atoms to form distorted MgKMg11 cuboctahedra that share corners with four equivalent Mg(7)Mg11Cr cuboctahedra; corners with six equivalent Mg(6)KMg11 cuboctahedra; corners with eight Mg(5,5)KMg10Cr cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(7)Mg11Cr cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four Mg(5,5)KMg10Cr cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra;  a faceface with one K(1)Mg10Cr2 cuboctahedra;  a faceface with one Mg(1)Mg12 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with three equivalent Mg(2)Mg12 cuboctahedra; faces with three equivalent Cr(1)K2Mg10 cuboctahedra; and faces with four Mg(5,5)KMg10Cr cuboctahedra. In the ninth Mg site, Mg(7) is bonded to one Mg(2); two equivalent Mg(3); two equivalent Mg(4); two equivalent Mg(6); four Mg(5,5); and one Cr(1) atom to form distorted MgMg11Cr cuboctahedra that share corners with four equivalent Mg(6)KMg11 cuboctahedra; corners with six equivalent Mg(7)Mg11Cr cuboctahedra; corners with eight Mg(5,5)KMg10Cr cuboctahedra; edges with two equivalent Mg(6)KMg11 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four Mg(5,5)KMg10Cr cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra;  a faceface with one Mg(2)Mg12 cuboctahedra;  a faceface with one Cr(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with three equivalent K(1)Mg10Cr2 cuboctahedra; faces with three equivalent Mg(1)Mg12 cuboctahedra; and faces with four Mg(5,5)KMg10Cr cuboctahedra. Cr(1) is bonded to two equivalent K(1); two equivalent Mg(7); four Mg(3,3); and four Mg(5,5) atoms to form CrK2Mg10 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra; corners with six equivalent Cr(1)K2Mg10 cuboctahedra; corners with eight equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(2)Mg12 cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with six equivalent Mg(6)KMg11 cuboctahedra.
KMg14Cr crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent Mg(6); four Mg(3,3); four Mg(5,5); and two equivalent Cr(1) atoms to form KMg10Cr2 cuboctahedra that share corners with four equivalent Mg(2)Mg12 cuboctahedra; corners with six equivalent K(1)Mg10Cr2 cuboctahedra; corners with eight equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(1)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with six equivalent Mg(7)Mg11Cr cuboctahedra. Both K(1)-Mg(6) bond lengths are 3.36 Å. There are two shorter (3.24 Å) and two longer (3.25 Å) K(1)-Mg(3,3) bond lengths. All K(1)-Mg(5,5) bond lengths are 3.33 Å. Both K(1)-Cr(1) bond lengths are 3.26 Å. There are nine inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2); two equivalent Mg(6); four equivalent Mg(4); and four Mg(5,5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Cr(1)K2Mg10 cuboctahedra; corners with six equivalent Mg(1)Mg12 cuboctahedra; corners with eight Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(2)Mg12 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; faces with four equivalent Mg(4)Mg12 cuboctahedra; and faces with six equivalent Mg(7)Mg11Cr cuboctahedra. Both Mg(1)-Mg(2) bond lengths are 3.26 Å. Both Mg(1)-Mg(6) bond lengths are 3.15 Å. There are two shorter (3.23 Å) and two longer (3.25 Å) Mg(1)-Mg(4) bond lengths. All Mg(1)-Mg(5,5) bond lengths are 3.20 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1); two equivalent Mg(7); four equivalent Mg(4); and four Mg(5,5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent K(1)Mg10Cr2 cuboctahedra; corners with six equivalent Mg(2)Mg12 cuboctahedra; corners with eight Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(1)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; faces with four equivalent Mg(4)Mg12 cuboctahedra; and faces with six equivalent Mg(6)KMg11 cuboctahedra. Both Mg(2)-Mg(7) bond lengths are 3.27 Å. There are two shorter (3.24 Å) and two longer (3.25 Å) Mg(2)-Mg(4) bond lengths. All Mg(2)-Mg(5,5) bond lengths are 3.14 Å. In the third Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Mg(3), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and two equivalent Cr(1) atoms to form distorted MgK2Mg8Cr2 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra; corners with four equivalent Mg(2)Mg12 cuboctahedra; corners with four equivalent Mg(4)Mg12 cuboctahedra; corners with six Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(5)KMg10Cr cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; and faces with eight Mg(5,5)KMg10Cr cuboctahedra. There is one shorter (3.23 Å) and one longer (3.29 Å) Mg(3)-Mg(3) bond length. Both Mg(3)-Mg(5) bond lengths are 3.27 Å. Both Mg(3)-Mg(6) bond lengths are 3.32 Å. Both Mg(3)-Mg(7) bond lengths are 3.19 Å. There is one shorter (3.21 Å) and one longer (3.28 Å) Mg(3)-Cr(1) bond length. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with four equivalent K(1)Mg10Cr2 cuboctahedra; corners with four equivalent Mg(3)K2Mg8Cr2 cuboctahedra; corners with four equivalent Cr(1)K2Mg10 cuboctahedra; corners with six equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Mg(4)Mg12 cuboctahedra; edges with four equivalent Mg(5)KMg10Cr cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(1)Mg12 cuboctahedra; faces with two equivalent Mg(2)Mg12 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; and faces with eight Mg(5,5)KMg10Cr cuboctahedra. There is one shorter (3.25 Å) and one longer (3.27 Å) Mg(4)-Mg(4) bond length. Both Mg(4)-Mg(5) bond lengths are 3.16 Å. Both Mg(4)-Mg(6) bond lengths are 3.11 Å. Both Mg(4)-Mg(7) bond lengths are 3.29 Å. In the fifth Mg site, Mg(3) is bonded to two equivalent K(1); two equivalent Mg(3); two Mg(5,5); two equivalent Mg(6); two equivalent Mg(7); and two equivalent Cr(1) atoms to form distorted MgK2Mg8Cr2 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra; corners with four equivalent Mg(2)Mg12 cuboctahedra; corners with four equivalent Mg(4)Mg12 cuboctahedra; corners with six Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four Mg(5,5)KMg10Cr cuboctahedra; edges with four equivalent Mg(6)KMg11 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Cr(1)K2Mg10 cuboctahedra; and faces with eight Mg(5,5)KMg10Cr cuboctahedra. There is one shorter (3.23 Å) and one longer (3.29 Å) Mg(3)-Mg(3) bond length. Both Mg(3)-Mg(5,5) bond lengths are 3.27 Å. Both Mg(3)-Mg(6) bond lengths are 3.32 Å. Both Mg(3)-Mg(7) bond lengths are 3.19 Å. There is one shorter (3.21 Å) and one longer (3.28 Å) Mg(3)-Cr(1) bond length. In the sixth Mg site, Mg(5) is bonded to one K(1), one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and one Cr(1) atom to form distorted MgKMg10Cr cuboctahedra that share corners with four equivalent Mg(6)KMg11 cuboctahedra; corners with four equivalent Mg(7)Mg11Cr cuboctahedra; corners with ten Mg(5,5)KMg10Cr cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(5)KMg10Cr cuboctahedra; edges with two equivalent Mg(6)KMg11 cuboctahedra; edges with two equivalent Mg(7)Mg11Cr cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra;  a faceface with one K(1)Mg10Cr2 cuboctahedra;  a faceface with one Mg(1)Mg12 cuboctahedra;  a faceface with one Mg(2)Mg12 cuboctahedra;  a faceface with one Cr(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with four equivalent Mg(4)Mg12 cuboctahedra. There is one shorter (3.14 Å) and one longer (3.38 Å) Mg(5)-Mg(5) bond length. There is one shorter (3.16 Å) and one longer (3.33 Å) Mg(5)-Mg(6) bond length. There is one shorter (3.21 Å) and one longer (3.29 Å) Mg(5)-Mg(7) bond length. The Mg(5)-Cr(1) bond length is 3.26 Å. In the seventh Mg site, Mg(5) is bonded to one K(1), one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and one Cr(1) atom to form distorted MgKMg10Cr cuboctahedra that share corners with four equivalent Mg(6)KMg11 cuboctahedra; corners with four equivalent Mg(7)Mg11Cr cuboctahedra; corners with ten equivalent Mg(5)KMg10Cr cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; edges with two equivalent Mg(5)KMg10Cr cuboctahedra; edges with two equivalent Mg(6)KMg11 cuboctahedra; edges with two equivalent Mg(7)Mg11Cr cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra;  a faceface with one K(1)Mg10Cr2 cuboctahedra;  a faceface with one Mg(1)Mg12 cuboctahedra;  a faceface with one Mg(2)Mg12 cuboctahedra;  a faceface with one Cr(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with four equivalent Mg(4)Mg12 cuboctahedra. The Mg(5)-Mg(4) bond length is 3.16 Å. There is one shorter (3.14 Å) and one longer (3.38 Å) Mg(5)-Mg(5) bond length. There is one shorter (3.16 Å) and one longer (3.33 Å) Mg(5)-Mg(6) bond length. There is one shorter (3.21 Å) and one longer (3.29 Å) Mg(5)-Mg(7) bond length. The Mg(5)-Cr(1) bond length is 3.26 Å. In the eighth Mg site, Mg(6) is bonded to one K(1); one Mg(1); two equivalent Mg(3); two equivalent Mg(4); two equivalent Mg(7); and four Mg(5,5) atoms to form distorted MgKMg11 cuboctahedra that share corners with four equivalent Mg(7)Mg11Cr cuboctahedra; corners with six equivalent Mg(6)KMg11 cuboctahedra; corners with eight Mg(5,5)KMg10Cr cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with two equivalent Mg(7)Mg11Cr cuboctahedra; edges with two equivalent Mg(1)Mg12 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four Mg(5,5)KMg10Cr cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra;  a faceface with one K(1)Mg10Cr2 cuboctahedra;  a faceface with one Mg(1)Mg12 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with three equivalent Mg(2)Mg12 cuboctahedra; faces with three equivalent Cr(1)K2Mg10 cuboctahedra; and faces with four Mg(5,5)KMg10Cr cuboctahedra. Both Mg(6)-Mg(7) bond lengths are 3.27 Å. In the ninth Mg site, Mg(7) is bonded to one Mg(2); two equivalent Mg(3); two equivalent Mg(4); two equivalent Mg(6); four Mg(5,5); and one Cr(1) atom to form distorted MgMg11Cr cuboctahedra that share corners with four equivalent Mg(6)KMg11 cuboctahedra; corners with six equivalent Mg(7)Mg11Cr cuboctahedra; corners with eight Mg(5,5)KMg10Cr cuboctahedra; edges with two equivalent Mg(6)KMg11 cuboctahedra; edges with two equivalent Mg(2)Mg12 cuboctahedra; edges with two equivalent Cr(1)K2Mg10 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four Mg(5,5)KMg10Cr cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra;  a faceface with one Mg(2)Mg12 cuboctahedra;  a faceface with one Cr(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(3)K2Mg8Cr2 cuboctahedra; faces with two equivalent Mg(6)KMg11 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with three equivalent K(1)Mg10Cr2 cuboctahedra; faces with three equivalent Mg(1)Mg12 cuboctahedra; and faces with four Mg(5,5)KMg10Cr cuboctahedra. The Mg(7)-Cr(1) bond length is 3.16 Å. Cr(1) is bonded to two equivalent K(1); two equivalent Mg(7); four Mg(3,3); and four Mg(5,5) atoms to form CrK2Mg10 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra; corners with six equivalent Cr(1)K2Mg10 cuboctahedra; corners with eight equivalent Mg(4)Mg12 cuboctahedra; edges with two equivalent K(1)Mg10Cr2 cuboctahedra; edges with four Mg(3,3)K2Mg8Cr2 cuboctahedra; edges with four equivalent Mg(7)Mg11Cr cuboctahedra; edges with eight Mg(5,5)KMg10Cr cuboctahedra; faces with two equivalent K(1)Mg10Cr2 cuboctahedra; faces with two equivalent Mg(7)Mg11Cr cuboctahedra; faces with two equivalent Mg(2)Mg12 cuboctahedra; faces with four Mg(3,3)K2Mg8Cr2 cuboctahedra; faces with four Mg(5,5)KMg10Cr cuboctahedra; and faces with six equivalent Mg(6)KMg11 cuboctahedra.