Scandium-rich ternary coloring variants of the cubic Ag7+xMg26–x type

The scandium-rich intermetallic compounds Sc 50 T 13 In 3 ( T = Ni, Ru, Pd) were synthesized from the elements in sealed tantalum crucibles in an induction furnace. The samples were studied through Guinier powder patterns and their structures were refined from single-crystal X-ray diffractometer data. The Sc 50 T 13 In 3 phases are site occupancy (coloring) variants of the aristotype Ag 7+ x Mg 26– x ( Fm 3 ¯ , cF 264). Refinements of the occupancy parameters indicated one mixed occupied site for each crystal, leading to the refined compositions Sc 50 Ni 13.16(1) In 2.84(1) , Sc 49.59(1) Ru 13 In 3.41(1) , and Sc 50 Pd 13.65(2) In 2.35(2) . The complex structures can be explained by a condensation of cubes (CN 8), sphenocorona (CN 10), and icosahedra (CN 12). The samples with nickel and palladium are Pauli paramagnets. Graphic abstract