Unique atom hyper-kagome order in Na4Ir3O8 and in low-symmetry spinel modifications.


Group-theoretical and thermodynamic methods of the Landau theory of phase transitions are used to investigate the hyper-kagome atomic order in structures of ordered spinels and a spinel-like Na4Ir3O8 crystal. The formation of an atom hyper-kagome sublattice in Na4Ir3O8 is described theoretically on the basis of the archetype (hypothetical parent structure… (More)
DOI: 10.1107/S2053273315003848