Reflecting electromagnetic waves from a surface of TbMnO3 with sinusoidal antiferromagnetic structure

A spectrum of coupled waves in TbMnO₃ with sinusoidal antiferromagnetic structure is investigated. Expressions for the activation frequencies are obtained, and temporal and spatial permittivity dispersions are considered. Frequency dependences for the reflectance of electromagnetic waves from the TbMnO₃ surface are calculated.     

Simple method for selective oxidation of 1,2-diols in water with KBrO3/KHSO4

Readily available off-the-shelf KBrO₃ and KHSO₄ have been used to selectively oxidize 1,2-diols in water as a solvent. Various cyclic 1,2-diols have been tolerated affording their corresponding α-hydroxy ketones in good yields.     

Origin of pressure-induced insulator-to-metal transition in the van der Waals compound FePS3 from first-principles calculations

Pressure-induced insulator-to-metal transition (IMT) has been studied in the van der Waals compound iron thiophosphate (FePS₃) using first-principles calculations within the periodic linear combination of atomic orbitals method with hybrid Hartree–Fock-DFT B3LYP functional. Our calculations reproduce correctly the IMT at ∼15 GPa, which is accompanied by a reduction of the unit cell volume and of the vdW gap. We found from the detailed analysis of the projected density of states that the 3p states of phosphorus atoms contribute significantly at the bottom of the conduction band. As a result, the collapse of the band gap occurs due to changes in the electronic structure of FePS₃ induced by relative displacements of phosphorus or sulfur atoms along the c-axis direction under pressure.     

Crystal Structure of Synthetic High-Chromium Analogue of Yimengite

Crystallography Reports - The structure of a potassium compound with the chemical formula K0.90Ti5.16Cr2.94Fe2.54Mg0.87Al0.22Mn0.30O19 has been investigated by single-crystal X-ray diffraction...     

Determination of temperature in a plasma jet emanating from a plasma torch with sectioned inter-electrode insert from the molecular emission spectrum of nitrogen

Results of application of a method for measuring the distribution of temperature in a nitrogen plasma jet emanating from a dc plasma torch with sectioned inter-electrode insert from the relative intensities of the molecular emission bands of nitrogen in the N₂ ⁺(B²Σ_u ⁺ − X²Σ_g ⁺) first negative and N₂(C³Π_u ⁺ − B³Π_g ⁺) second positive systems are reported. The emission spectra were registered using a small-size spectrometer with medium-range spectral resolution enabling a contour analysis of ro-vibrational bands in molecular emission spectra. The obtained distribution of temperature was compared with the distribution that was determined from the emission lines due to copper atoms and with the mean-mass plasma temperature of the air plasma jet.