Chemical speciation in Gd−Cd−M (M=Zn, Au) quasicrystal approximants

We investigated the effect of partial replacement Cd by M=Au and Zn in crystal structure 1/1 Tsai-type quasicrystal approximant (AC) GdCd6. Compositionally homogeneous single samples Gd(Cd0.87Zn0.13(1))6 Gd(Cd0.80Au0.20(1))6 were grown from melts Gd5(Cd0.8Zn0.2)100 Gd1(Cd0.9Au0.1)100, respectively, isolated centrifugation. The M for substitution GdCd6 is accompanied with a sizeable reduction cubic unit cell parameter, 15.514(2) Å to 15.329(1) (Zn) 15.314(1) (Au). Site preferences established X-ray diffraction data. A clear preference atomic sites Au noted which compared earlier reported Yb(Cd0.75Mg0.25)6. Three two out total seven crystallographic defining accept preferably metals more less electronegative than Cd, are classified as negatively positively polarized binary AC.