KCaMg6 crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent Ca(1); two equivalent Mg(4); four Mg(1,1); and four Mg(3,3,3,3) atoms to form KCa2Mg10 cuboctahedra that share corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with six equivalent K(1)Ca2Mg10 cuboctahedra; corners with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; faces with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent Mg(2)Ca2Mg10 cuboctahedra. Ca(1) is bonded to two equivalent K(1); two equivalent Mg(2); four Mg(1,1,1); and four Mg(3,3) atoms to form CaK2Mg10 cuboctahedra that share corners with four equivalent Mg(2)Ca2Mg10 cuboctahedra; corners with six equivalent Ca(1)K2Mg10 cuboctahedra; edges with two equivalent Mg(2)Ca2Mg10 cuboctahedra; edges with four equivalent K(1)Ca2Mg10 cuboctahedra; edges with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent Mg(4)K2Mg10 cuboctahedra. There are nine inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the second Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the third Mg site, Mg(2) is bonded to two equivalent Ca(1); two equivalent Mg(4); four Mg(1,1,1); and four Mg(3,3) atoms to form distorted MgCa2Mg10 cuboctahedra that share corners with four equivalent Ca(1)K2Mg10 cuboctahedra; corners with six equivalent Mg(2)Ca2Mg10 cuboctahedra; edges with two equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(4)K2Mg10 cuboctahedra; edges with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent K(1)Ca2Mg10 cuboctahedra. In the fourth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. In the fifth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. In the sixth Mg site, Mg(4) is bonded to two equivalent K(1); two equivalent Mg(2); four Mg(1,1); and four Mg(3,3,3,3) atoms to form distorted MgK2Mg10 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with six equivalent Mg(4)K2Mg10 cuboctahedra; corners with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; edges with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; faces with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent Ca(1)K2Mg10 cuboctahedra. In the seventh Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. In the eighth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. In the ninth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra.
KCaMg6 crystallizes in the orthorhombic Amm2 space group. K(1) is bonded to two equivalent Ca(1); two equivalent Mg(4); four Mg(1,1); and four Mg(3,3,3,3) atoms to form KCa2Mg10 cuboctahedra that share corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with six equivalent K(1)Ca2Mg10 cuboctahedra; corners with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; faces with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent Mg(2)Ca2Mg10 cuboctahedra. Both K(1)-Ca(1) bond lengths are 3.49 Å. Both K(1)-Mg(4) bond lengths are 3.44 Å. All K(1)-Mg(1,1) bond lengths are 3.42 Å. There are two shorter (3.40 Å) and two longer (3.54 Å) K(1)-Mg(3,3,3,3) bond lengths. Ca(1) is bonded to two equivalent K(1); two equivalent Mg(2); four Mg(1,1,1); and four Mg(3,3) atoms to form CaK2Mg10 cuboctahedra that share corners with four equivalent Mg(2)Ca2Mg10 cuboctahedra; corners with six equivalent Ca(1)K2Mg10 cuboctahedra; edges with two equivalent Mg(2)Ca2Mg10 cuboctahedra; edges with four equivalent K(1)Ca2Mg10 cuboctahedra; edges with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent Mg(4)K2Mg10 cuboctahedra. Both Ca(1)-Mg(2) bond lengths are 3.44 Å. There are two shorter (3.35 Å) and two longer (3.60 Å) Ca(1)-Mg(1,1,1) bond lengths. All Ca(1)-Mg(3,3) bond lengths are 3.38 Å. There are nine inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. There is one shorter (3.34 Å) and one longer (3.55 Å) Mg(1)-Mg(1) bond length. There is one shorter (3.47 Å) and one longer (3.48 Å) Mg(1)-Mg(2) bond length. Both Mg(1)-Mg(3) bond lengths are 3.38 Å. Both Mg(1)-Mg(4) bond lengths are 3.38 Å. In the second Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. There is one shorter (3.47 Å) and one longer (3.48 Å) Mg(1)-Mg(2) bond length. Both Mg(1)-Mg(3) bond lengths are 3.38 Å. Both Mg(1)-Mg(4) bond lengths are 3.38 Å. In the third Mg site, Mg(2) is bonded to two equivalent Ca(1); two equivalent Mg(4); four Mg(1,1,1); and four Mg(3,3) atoms to form distorted MgCa2Mg10 cuboctahedra that share corners with four equivalent Ca(1)K2Mg10 cuboctahedra; corners with six equivalent Mg(2)Ca2Mg10 cuboctahedra; edges with two equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(4)K2Mg10 cuboctahedra; edges with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent K(1)Ca2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.41 Å. The Mg(2)-Mg(1) bond length is 3.47 Å. All Mg(2)-Mg(3,3) bond lengths are 3.39 Å. In the fourth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. Both Mg(3)-Mg(1) bond lengths are 3.38 Å. There is one shorter (3.41 Å) and one longer (3.47 Å) Mg(3)-Mg(3) bond length. There is one shorter (3.47 Å) and one longer (3.48 Å) Mg(3)-Mg(4) bond length. In the fifth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. Both Mg(3)-Mg(1) bond lengths are 3.38 Å. There is one shorter (3.47 Å) and one longer (3.48 Å) Mg(3)-Mg(4) bond length. In the sixth Mg site, Mg(4) is bonded to two equivalent K(1); two equivalent Mg(2); four Mg(1,1); and four Mg(3,3,3,3) atoms to form distorted MgK2Mg10 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with six equivalent Mg(4)K2Mg10 cuboctahedra; corners with eight Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; edges with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; faces with four Mg(3,3,3,3)K2Ca2Mg8 cuboctahedra; and faces with six equivalent Ca(1)K2Mg10 cuboctahedra. Both Mg(4)-Mg(3,3) bond lengths are 3.47 Å. In the seventh Mg site, Mg(1) is bonded in a 12-coordinate geometry to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms. Both Mg(1)-K(1) bond lengths are 3.42 Å. There is one shorter (3.34 Å) and one longer (3.55 Å) Mg(1)-Mg(1) bond length. Both Mg(1)-Mg(4) bond lengths are 3.38 Å. In the eighth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. Both Mg(3)-Ca(1) bond lengths are 3.38 Å. Both Mg(3)-Mg(2) bond lengths are 3.39 Å. There is one shorter (3.41 Å) and one longer (3.47 Å) Mg(3)-Mg(3) bond length. In the ninth Mg site, Mg(3) is bonded to two equivalent K(1), two equivalent Ca(1), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), and two equivalent Mg(4) atoms to form distorted MgK2Ca2Mg8 cuboctahedra that share corners with four equivalent K(1)Ca2Mg10 cuboctahedra; corners with four equivalent Mg(4)K2Mg10 cuboctahedra; corners with ten Mg(3,3,3)K2Ca2Mg8 cuboctahedra; edges with two equivalent K(1)Ca2Mg10 cuboctahedra; edges with two equivalent Mg(3)K2Ca2Mg8 cuboctahedra; edges with two equivalent Mg(4)K2Mg10 cuboctahedra; edges with four equivalent Ca(1)K2Mg10 cuboctahedra; edges with four equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent K(1)Ca2Mg10 cuboctahedra; faces with two equivalent Ca(1)K2Mg10 cuboctahedra; faces with two equivalent Mg(2)Ca2Mg10 cuboctahedra; faces with two equivalent Mg(4)K2Mg10 cuboctahedra; and faces with four Mg(3,3)K2Ca2Mg8 cuboctahedra. Both Mg(3)-Ca(1) bond lengths are 3.38 Å. Both Mg(3)-Mg(2) bond lengths are 3.39 Å.