Comparative structural study of the disordered MCd6 quasicrystal approximants
Several of the MCd6 approximants (M=Pr, Nd, Sm, Eu, Gd, Dy, Yb, Y, and Ca) to the MCd5.7 quasicrystals (M=Yb and Ca) have been synthesized and their structures have been refined from single-crystal x-ray-diffraction data; the different types of disorder of the central Cd4 tetrahedra located in the dodecahedral cavities of these closely related compounds have been examined and mutually compared. A