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Multiferroic materials, such as nanostructured h-YMnO3, are expected to fulfill a crucial role as active components of technological devices, particularly for information storage. Herein, we report on the template mediated sol–gel synthesis of unique one-dimensional nanostructured motifs of hexagonal phase YMnO3, possessing a space group of P63cm. We found that the inherent morphology of the as-obtained h-YMnO3nanostructures was directly impacted by the chemical composition of the employed membrane. Specifically, the use of anodic alumina and polycarbonate templates promoted nanotube and nanowire formation, respectively. Isolated polycrystalline nanotubes and single crystalline nanowires possessed diameters of 276 ± 52 nm, composed of 17 nm particulate constituent grains, and 125 ± 21 nm, respectively, with lengths of up to several microns. The structures and compositions of all our as-prepared products were probed by XRD, SEM, HRTEM, EXAFS, XANES, SAED, and far-IR spectroscopy. In the specific case of nanowires, we determined that the growth direction was mainly along the c-axis and that discrete, individual structures gave rise to expected ferroelectric behavior. Overall, our YMnO3samples evinced the onset of a spin-glass transition at 41 ± 1 K for both templateless bulk control and nanowire samples but at 26 ± 3 K for nanotubes. Interestingly, only the as-synthesized crystalline nanotubular mesh gave rise to noticeably enhanced magnetic properties (i.e., a higher magnetic moment of 3.0 μB/Mn) as well as a lower spin-glass transition temperature, attributable to a smaller constituent crystallite size. Therefore, this work not only demonstrates our ability to generate viable one-dimensional nanostructures of a significant and commercially relevant metal oxide but also contributes to an understanding of structure–property correlations in these systems.

Atomic-resolution transmission electron microscopy is used to investigate the microstructure of polycrystalline UPt3. While the host material is the previously reported hexagonal Ni3Sn structure, a second phase having the double-hexagonal Ni3Ti structure is also identified.

We have made samples of La1.85Ba0.15CuO4-y with varying heat treatments. We have measured their dc magnetization and electron paramagnetic resonance, and have examined them by electron microscopy and electron diffraction. For samples annealed only a few hours, cooling the material below 5 K causes a magnetic transition and a thermal hysteresis. These observations, taken with the EPR data, suggest a possible spin-glass or ferromagnetic phase. Annealing samples in an oxygen atmosphere appears to remove that magnetic phase. For the phase with the K2NiF4 structure, no superlattice spots are seen in electron diffraction at room temperature or at 77 K.

Experimental efforts to characterize and develop an understanding of non Fermi liquid (NFL) behavior at low temperature in f-electron materials are reviewed for three f-electron systems: M1-xUxPd3 (M = Sc, Y), U1-xThxPd2Al3, and UCu5-xPdx. The emerging systematics of NFL behavior in f-electron systems, based on the present sample of nearly ten f-electron systems, is updated. Many of the f-electron systems exhibit the following temperature dependences of the electrical resistivity p, specific heat C, and magnetic susceptibility ? for T « T0, where To is a characteristic temperature: P(T) ~ 1 –aT/T0, where a < 0 or > 0, C(T)/T ~ (-1/To) In (T/bT0), and ?(T) ~ 1 -c(T/To)1/2. In several of the f-electron systems, the characteristic temperature To can be identified with the Kondo temperature Tk.

Single‐crystalline SrRuO3submicrometer‐sized particles are synthesized by reaction of Sr(OH)2·8H2O, RuO2nanoparticles, and 1% mineral oil in Triton X‐100 surfactant in a NaCl/KCl flux (porcelain crucible, air, 700 °C; quenching).

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