Search

Pnictide oxides exhibit a rich crystal chemistry, which is much more than the ZrCuSiAs structure of LaFeAsO, the mother-structure of the 1-1-1-1 materials. The present micro-review focuses on different dimensionalities in the oxidic and the pnictide substructures, largely extending the structural building units. The second part concerns BaAl4/ThCr2Si2 superstructures, which extend the crystal chemistry of BaFe2As2. Key parameters for superstructure formation are either an ordering of the transition metal and p-element atoms ( coloring) or an ordering of vacancies. [ABSTRACT FROM AUTHOR]

Polycrystalline La3Cu4P4O2 (I) and La5Cu4P4O4Cl2 (II) are prepared by solid state reaction of stoichiometric amounts of La, Cu2O, red P, and LaCl3 (evacuated silica tubes, 1. [ABSTRACT FROM AUTHOR]

Ce23Ru7Zn4 is obtained by melting of the elements in stoichiometric amounts (Nb ampoule, 1500 K, 10 min). [ABSTRACT FROM AUTHOR]

The title compounds are prepared by solid state reaction of the rare earth metals, their appropriate oxides, finely dispersed gold, and red phosphorus (sealed silica tube, 1173 K, 72 h). [ABSTRACT FROM AUTHOR]