Synthesis of Zintl Phase Metal Silicide Thermoelectric Materials in Magnesium/Zinc Flux.

Zintl phases have potential applications as thermoelectric materials for power generation and cooling owing to their complex crystal structures and unique electronic properties. We carried out reactions of silicon with barium and strontium in excess Mg/Zn flux to synthesize (Ba/Sr)MgSi Zintl phases, investigating the effect of varying Ba/Sr ratio on site mixing and thermoelectric properties. (Ba/Sr)MgSi compounds with 0 < < 3 are charge-balanced Zintl phases which adopt the hexagonal HoNiP structure type (space group 6̅2).

Temperature-Dependent Products in Gallium Flux Reactions of Cerium and Transition Metals.

Reactions of cerium and transition metals in excess molten gallium were carried out, exploring the formation of different cerium intermetallics as the flux reaction is cooled. Ce//Ga reactions with = Ni, Cu, Pd, Ag, and Zn produce a high-temperature product, which converts into a low-temperature product in the flux. The phases present in the flux mixture were determined by quenching identical reactions at 750 and 300 °C and identifying the isolated products using elemental analysis and X-ray diffraction.

Metal Flux Growth of Lanthanide Carbide Hydrides Using Anthracene.

Reactions of anthracene in Ln/T eutectic mixtures (Ln = La, Yb; T = Ni, Cu) have produced crystals of new complex lanthanide carbide hydride phases. The thermal decomposition of anthracene provides a source of both carbon and hydrogen. LaCH forms in space group with unit cell parameters = 7.

Flux Growth of an Intermetallic with Interstitial Fluorides Decomposition of a Fluorocarbon.

La(FeC)F was grown as large crystals by reacting iron in a La/Ni eutectic flux in the presence of decafluorobiphenyl (CF) which acts as both a carbon and fluoride source. This mild fluorinating technique enables the isolation of an intermetallic product containing fluoride interstitials, as opposed to forming ionic metal fluorides. The compound adopts a structure in the hexagonal crystal system with space group 6̅ which features FeC units composed of a central iron atom coordinated by three ethylenide units in a trigonal planar configuration.