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A variety of binary intermetallic compounds of late transition metals with low-melting post-transition metals have been synthesized in bulk quantities by reacting molten metal dispersions with fine metal powders in hot polyalcohol solvents. Fourteen distinct intermetallics were formed using this technique: SbSn, FeSn2, Cu6Sn5, CoSn3, Ni3Sn4, FeGa3, NiGa4, Cu9Ga4, CoGa3, Ni2In3, InSb, In5Bi3, InBi, and Bi3Ni. Notable among these are a low-temperature phase (α-CoSn3), textured intermetallic powders with anisotropic morphologies (α-CoSn3 and FeSn2), and superconductors (Bi3Ni and In5Bi3). Reaction pathway studies suggest that the molten low-melting metals diffuse into the larger higher melting powders, forming intermetallic compounds directly in a liquid-phase medium from bulk-scale powders of the constituent elements.

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A series of samples with the composition Zr 0.5 Hf 0.5 Co 1Àx Ir x Sb 0.99 Sn 0.01 (x = 0.0 to 0.7) were synthesized by high-temperature solid-state reaction at 1173 K. High-density pellets of the powders were obtained using hot press (HP) and spark plasma sintering (SPS) techniques. The thermoelectric properties of the pellets were measured from 300 K to 750 K. Independently of the pressing conditions, all Ir-containing samples (x > 0) showed p-type semiconducting behavior. At 300 K, the electrical conductivity and thermopower of Zr 0.5 Hf 0.5 Co 1Àx Ir x Sb 0.99 Sn 0.01 materials surprisingly increased with increasing Ir concentration. The largest electrical conductivity and thermopower values of 150 S/cm and 140 lV/K, respectively, were observed at 300 K for x = 0.7. The thermal conductivity of the synthesized materials decreased with increasing Ir content, went through a minimum value (x = 0.3), and increased thereafter with further addition of Ir. Pellets fabricated by SPS showed smaller thermal conductivity than pellets of the same composition obtained from uniaxial hot pressing. A thermal conductivity value of $2.0 W/m K was observed at 300 K for an SPS pellet with the composition Zr 0.5 Hf 0.5 Co 0.5 Ir 0.5 Sb 0.99 Sn 0.01 . The thermal conductivity of Zr 0.5 Hf 0.5 -Co 1Àx Ir x Sb 0.99 Sn 0.01 decreased with rising temperature, and the smallest value of $1.5 W/m K was observed at 750 K for the SPS specimen with x = 0.5.

Gram-scale quantities of Eu2Ti2O7 with a [110] layered perovskite structure have been synthesized at ambient pressure by thermally oxidizing (750−900 °C) perovskite-type EuTiO3. Eu2Ti2O7 is type 1 phase matchable and shows a SHG efficiency of 80 × α-SiO2.

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Titanium I 4300 Ambient-Pressure Synthesis of SHG-Active Eu2Ti2O7 with a [110] Layered Perovskite Structure: Suppressing Pyrochlore Formation by Oxidation of Perovskite-Type EuTiO3. -Gram-scale quantities of the title compound are synthesized by heating EuTiO3 (obtained by heating stoichiometric amounts of Eu2O3 and TiO2 for 24 h at 1000°C under flowing H2/Ar) in air or O2. XRD suggests that Eu2Ti2O7 is isostructural with La2Ti2O7 and crystallizes in the monoclinic space group P21 at room temperature. Powder SHG measurements indicate that the compound exhibits an SHG efficiency of approximately 80 times that of α-SiO2. -(HENDERSON, N. L.; BAEK, J.; HALASYAMANI*, P. S.; SCHAAK, R. E.; Chem.