Metal-rich phosphides RE5Ir19P12 with Sc5Co19P12 type structure

Crystal and electronic structure of the new ternary phosphide Ho5Pd19P12

The title compound was prepared from the pure elements by sintering. The crystal structure was investigated by means of powder X-ray diffraction data. Ho5Pd19P12 exhibits the hexagonal Ho5Ni19P12-type structure with space group P 6 ‾ 2 m $P‾{6}2m$ , a = 13.1342(2), c = 3.9839(1) Å, R I = 0.060, R p = 0.080. The crystal structure can be described as a combination of two types of the structural units, [HoPd6P3] and [Ho3Pd10P6], respectively, mutually displaced by 1/2 along the crystallographic c axis. Quantum chemical calculations have been performed to analyze the electronic structure and provide deeper insight into the structure-property relationships. The results of the quantum chemical calculations indicate that the material features metallic bonding between Ho and Pd and covalent bonding between Pd and P.

Electron-deficient copper pnictides: A2Mg3Cu9Pn7 (A = Sr, Eu; Pn = P, As) and Eu5Mg2.39Cu16.61As12

Five pnictide Zintl compounds, A₂Mg₃Cu₉Pn₇ (A = Sr, Eu; Pn = P, As) and Eu₅Mg_2.39Cu_16.61As₁₂, were synthesized from the Pb-flux reactions. The anion structures of these compounds can be described as being composed of edge- or corner-sharing CuPn₄ tetrahedra, which construct complex 3D frameworks with cations filled into the cavities.