Epitaxial La 0.67 Sr 0.33 MnO 3 ͑LSMO͒ ferromagnetic thin films were coherently grown on NdGaO 3 ͑NGO͒ substrates with different crystal orientations of the surface plane. On the ͑110͒ o -and ͑001͒ o -oriented substrates, the film grows in the ͑001͒ pc orientation, and on the ͑100͒ o -, ͑010͒ o -, and ͑112͒ o -oriented substrates the film is ͑011͒ pc oriented ͑we will use subindices o and pc for the orthorhombic and pseudocubic crystal structures, respectively͒. The lattice parameters and pseudocube angles of the deformed LSMO pseudocube have been determined from x-ray diffraction measurements. The in-plane magnetic easy and hard directions of these films have been determined from the dependence of the remnant magnetization on the angle of the in-plane applied field. For all substrate orientations there is a strong in-plane uniaxial magnetic anisotropy, determined by the crystal directions of the substrate surface. The easy and hard magnetic-anisotropy directions are explained consistently by the ͑bulk͒ inverse magnetostriction model, except for the film on NGO ͑112͒ o .
We report the formation of a nonmagnetic band insulator at the isopolar interface between the antiferromagnetic Mott-Hubbard insulator LaTiO_{3} and the antiferromagnetic charge transfer insulator LaFeO_{3}. By density-functional theory calculations, we find that the formation of this interface state is driven by the combination of O band alignment and crystal field splitting energy of the t_{2g} and e_{g} bands. As a result of these two driving forces, the Fe 3d bands rearrange and electrons are transferred from Ti to Fe. This picture is supported by x-ray photoelectron spectroscopy, which confirms the rearrangement of the Fe 3d bands and reveals an unprecedented charge transfer up to 1.2±0.2 e^{-}/interface unit cell in our LaTiO_{3}/LaFeO_{3} heterostructures.
Ru(NO)-salen complexes were found to catalyze asymmetric aerobic oxygen atom transfer reactions such as sulfide oxidation and epoxidation in the presence of water under visible light irradiation at room temperature. Oxidation of sulfides including alkyl aryl sulfides and 2-substituted 1,3-dithianes using complex 2 as the catalyst proceeded with moderate to high enantioselectivity of up to 98% ee, and epoxidation of conjugated olefins using complex 3 as the catalyst proceeded with good to high enantioselectivity of 76-92% ee. Unlike biological oxygen atom transfer reactions that need a proton and electron transfer system, this aerobic oxygen atom transfer reaction requires neither such a system nor a sacrificial reductant. Although the mechanism of this oxidation has not been completely clarified, some experimental results support the notion that an aqua ligand coordinated with the ruthenium ion serves as a proton transfer agent for the oxygen activation process, and it is recycled and used as the proton transfer mediator during the process. Thus, we have achieved catalytic asymmetric oxygen atom transfer reaction using molecular oxygen that can be carried out under ambient conditions.
Mixed-anion perovskites such as oxynitrides, oxyfluorides, and oxyhydrides have flexibility in their anion arrangements, which potentially enables functional material design based on coordination chemistry. However, difficulty in the control of the anion arrangement has prevented the realization of this concept. In this study, we demonstrate strain engineering of the anion arrangement in epitaxial thin films of the CaSrTaON perovskite oxynitrides. Under compressive epitaxial strain, the axial sites in TaON octahedra tend to be occupied by nitrogen rather than oxygen, which was revealed by N and O K-edge linearly polarized X-ray absorption near-edge structure (LP-XANES) and scanning transmission electron microscopy combined with electron energy loss spectroscopy. Furthermore, detailed analysis of the LP-XANES indicated that the high occupancy of nitrogen at the axial sites is due to the partial formation of a metastable trans-type anion configuration. These results are expected to serve as a guide for the material design of mixed-anion compounds based on their anion arrangements.
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