Half Antiperovskites: IV. Crystallographic and Electronic Structure Investigations on A 2 Rh 3 S 2 ( A = In, Sn, Tl, Pb, Bi)

The crystal and electronic structures of ordered half antiperovskites A 2 Rh 3 S 2 = A Rh 3/2 S ( A = In, Sn, Tl, Pb, Bi) are investigated. From powder and single crystal data superstructures, rhodium site ordering, trends in bonding and coordination are analysed with respect to the A site atom. Comparisons address isotypic and isoelectronic relations to monoclinic parkerite (Bi 2 Ni 3 S 2 ) type superconductors, the trigonal half‐metal ferromagnet Sn 2 Co 3 S 2 , and rhodium‐containing antiperovskites. Local structure and bonding is analysed with respect to the ordered occupation of half of S 2 A 4 sites (= perovskite oxygen sites) and interlinking to 2D networks [Rh 3 S 2 ] ∞ δ – by face‐, edge‐ and corner‐sharing. The theoretical part includes DFT band structure and ELF calculations, systematic comparisons to rhodium and antiperovskites, as well as spin‐polarised calculations on Sn 2 Rh 3 S 2 and Pb 2 Rh 3 S 2 .