The structure of Y-Al13−xCo4 (x = 0.8) analyzed by single crystal X-ray diffraction coupled with anomalous X-ray scattering

The structure of Y-Al13−xCo4 (x = 0.8) has been analyzed by single crystal X-ray diffraction: space group C2/m (No.12), a = 17.0525 (20) Å, b = 4.1059(6) Å, c = 7.5047(9) Å, β = 116.01(1)°. Y-Al13−0.8Co4 is isostructural with a ternary Y-Al13−x(Co,Ni)4 and crystallized at the Al-poor region close to Al13Co4. The distribution of Co was also confirmed by anomalous X-ray scattering (AXS) at Co K absorption edge. Present analysis revealed the Co distribution at Co(1) and Co(2) sites, only, by suggesting unique pentagonal atomic columns with a period of 4 Å different from that observed in Al11Co4.