Complex intermetallic compounds in the Mg-Ir system solved by powder diffraction

摘要

The crystal structures of two new topologically close-packed intermetallic compounds, MgIr (Cmca, 25 atoms) and Mg_(2-x)Ir_(3+x) (x=0.067, C2/m, 11 atoms) were fully characterized by high resolution synchrotron powder diffraction and global optimization of a structural model in direct space. The simulated annealing algorithm (in parallel tempering mode) and computer program Fox were used.