Synthesis and crystal structures of RE₇Zn_21+xSi_2–x [RE = Ce, Pr, and Nd; 0.09 (1) < x < 0.95 (1)]

The structures of the ternary compounds RE₇Zn_21+xSi_2−x [RE = Ce, Pr, and Nd; 0.09 (1) < x < 0.95 (1)] are reported. Important structural features in these compounds are the large polyhedral cages made up of Zn atoms and the Si atoms in trigonal planar coordination. A small occupational Zn–Si disorder is found at the Si site.