| Abstrakt: |
Y6Cr4+xAl43?x(x= 2.57); space group P63/mcm, a= 10.8601(1) ?, c= 17.6783(3) ?, V= 1805.7(1) ?3, Z=2; isostructural to Yb6Cr4+xAl43?x, (x=1.76) with two aluminium sites partially occupied by chromium (44% and 27% Cr). YCr4?xAl8+x(x=1.22); space group I4/mmm, a= 9.0299(2) ?, c= 5.1208(2) ?, V=417.55(3) ?3, Z=2, disordered variant of CeMn4Al8with one chromium site (8f) partially occupied by aluminium (33% Al); X-ray powder diffraction data were collected on a well-crystallized multiphase sample containing 43 wt.% of Y6Cr4+xAl43?x, 27 wt.% of Y2Cr8?xAl16+x, 16 wt.% of Al, 13 wt.% of YAl3, and traces of Y2O3. Structure refinement converged at Rwp= 2.0% and RB= 3.5, 3.6% resp. for a total of 78 parameters and 1190 reflections. |
