Using magnetization, dielectric constant, and neutron diffraction measurements on a high quality single crystal of YBaCuFeO (YBCFO), we demonstrate that the crystal shows two antiferromagnetic transitions at [Formula: see text] K and [Formula: see text] K, and displays a giant dielectric constant with a characteristic of the dielectric relaxation at T . It does not show the evidence of the electric polarization for the crystal used for this study. The transition at T corresponds with a paramagnetic to antiferromagnetic transition with a magnetic propagation vector doubling the unit cell along three crystallographic axes. Upon cooling, at T , the commensurate spin ordering transforms to a spiral magnetic structure with a propagation vector of ([Formula: see text] [Formula: see text] [Formula: see text]), where [Formula: see text], [Formula: see text], and [Formula: see text] are odd, and the incommensurability δ is temperature dependent. Around the transition boundary at T, both commensurate and incommensurate spin ordering coexist.

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Effects of electronic and atomic structures of V‐doped 2D layered SnS2 are studied using X‐ray spectroscopy for the development of photocatalytic/photovoltaic applications. Extended X‐ray absorption fine structure measurements at V K‐edge reveal the presence of VO and VS bonds which form the intercalation of tetrahedral OVS sites in the van der Waals (vdW) gap of SnS2 layers. X‐ray absorption near‐edge structure (XANES) reveals not only valence state of V dopant in SnS2 is ≈4+ but also the charge transfer (CT) from V to ligands, supported by V Lα,β resonant inelastic X‐ray scattering. These results suggest V doping produces extra interlayer covalent interactions and additional conducting channels, which increase the electronic conductivity and CT. This gives rapid transport of photo‐excited electrons and effective carrier separation in layered SnS2. Additionally, valence‐band photoemission spectra and S K‐edge XANES indicate that the density of states near/at valence‐band maximum is shifted to lower binding energy in V‐doped SnS2 compare to pristine SnS2 and exhibits band gap shrinkage. These findings support first‐principles density functional theory calculations of the interstitially tetrahedral OVS site intercalated in the vdW gap, highlighting the CT from V to ligands in V‐doped SnS2.

Two isothermal sections of the Ni-Cr-Ta ternary system at 1200 °C and 1300 °C have been determined by using electron probe microanalysis, energy dispersive spectroscopy and differential scanning calorimeter. A Laves phase (Ni, Cr)2Ta(HT)(C14 structure) with large solid solubility stabilized by the Ni addition was determined in both two isothermal sections. The composition range of this phase was about 25.8–66.0 at.% Cr, 2.5-44.3 at.% Ni, and 24.0-40.0 at.% Ta at 1200 °C, which increased with raising temperature. The melting point of the Ni-Cr alloys decreased with the addition of Ta. No ternary compound was found in both these two isothermal sections. The present work could be significant for practical application of nickel-based alloys and future thermodynamics assessment of the Ni-Cr-Ta ternary system.

Two isothermal sections of the Ni-V-Ta ternary system at 1200 °C and 1000 °C have been experimentally established using X-ray diffraction, electron probe microanalysis, energy dispersive spectroscopy, and differential scanning calorimeter with equilibrated key alloys. The equilibrium composition of each phase is measured by electron probe microanalysis and energy dispersive spectroscopy. The results indicate that: (1) nine three-phase and eight three-phase regions were confirmed in the isothermal section at 1200 °C and 1000 °C, respectively; (2) the C14 phase with a large solubility of about 51.2 at. % Ni was observed at 1200 °C, while it forms a single-phase region at 1000 °C; (3) a small liquid region was confirmed at 1200 °C, but disappeared at 1000 °C.