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Cationic rearrangement is a compelling strategy for producing desirable physical properties by atomic-scale manipulation. However, activating ionic diffusion typically requires high temperature, and in some cases also high pressure in bulk oxide materials. Herein, we present the cationic rearrangement in bulk Mn2FeMoO6 at unparalleled low temperatures of 150-300 oC. The irreversible ionic motion at ambient pressure, as evidenced by real-time powder synchrotron X-ray and neutron diffraction, and second harmonic generation, leads to a transition from a Ni3TeO6-type to an ordered-ilmenite structure, and dramatic changes of the electrical and magnetic properties. This work demonstrates a remarkable cationic rearrangement, with corresponding large changes in the physical properties in a bulk oxide at unprecedented low temperatures. [ABSTRACT FROM AUTHOR]

Purification of C2H4 from an C2H4 /C2H6 mixture is one of the most challenging separation processes, which is achieved mainly through energy‐intensive, cryogenic distillation in industry. Sustainable, non‐distillation methods are highly desired as alternatives. We discovered that the fluorinated bis(pyrazolyl)borate ligand supported copper(I) complex {[(CF3)2Bp]Cu}3 has features very desirable in an olefin–paraffin separation material. It binds ethylene exclusively over ethane generating [(CF3)2Bp]Cu(C2H4). This molecular compound exhibits extremely high and record ideal adsorbed solution theory (IAST) C2H4 /C2H6 gas separation selectivity, affording high purity (>99.5 %) ethylene that can be readily desorbed from separation columns. In‐situ PXRD provides a "live" picture of the reversible conversion between [(CF3)2Bp]Cu(C2H4) and the ethylene‐free sorbent in the solid‐state, driven by the presence or removal of C2H4. Molecular structures of trinuclear {[(CF3)2Bp]Cu}3 and mononuclear [(CF3)2Bp]Cu(C2H4) are also presented. [ABSTRACT FROM AUTHOR]

The frontpiece of the journal is presented depicting cationic rearrangement in metal oxide.

The first transition-metal-only double perovskite compound, Mn2+2Fe3+Re5+O6, with 17 unpaired d electrons displays ferrimagnetic ordering up to 520 K and a giant positive magnetoresistance of up to 220 % at 5 K and 8 T. These properties result from the ferrimagnetically coupled Fe and Re sublattice and are affected by a two-to-one magnetic-structure transition of the Mn sublattice when a magnetic field is applied. Theoretical calculations indicate that the half-metallic state can be mainly attributed to the spin polarization of the Fe and Re sites. [ABSTRACT FROM AUTHOR]

Above-room-temperature polar magnets are of interest due to their practical applications in spintronics. Here we present a strategy to design high-temperature polar magnetic oxides in the corundum-derived A2BB′O6 family, exemplified by the non-centrosymmetric ( R3) Ni3TeO6-type Mn2+2Fe3+Mo5+O6, which shows strong ferrimagnetic ordering with TC=337 K and demonstrates structural polarization without any ions with ( n−1)d10 ns0, d0, or stereoactive lone-pair electrons. Density functional theory calculations confirm the experimental results and suggest that the energy of the magnetically ordered structure, based on the Ni3TeO6 prototype, is significantly lower than that of any related structure, and accounts for the spontaneous polarization (68 μC cm−2) and non-centrosymmetry confirmed directly by second harmonic generation. These results motivate new directions in the search for practical magnetoelectric/multiferroic materials. [ABSTRACT FROM AUTHOR]

Polar LiNbO3‐type magnetic oxides have been extended, for the first time, to the A2BB′O6 family. Mn2+2Fe3+M5+O6 (M=Nb, Ta), synthesized at high pressure, adopt a polar structure, as demonstrated by electron diffraction and the second harmonic generation effect, and they have interesting magnetic properties. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated multicenter bonding in dianionic tetracyanoethylene (TCNE) dimers through Raman spectroscopy. In this study, the stretching force constant 0.45 mdyn Å-1 was determined through analysis of the Raman spectrum of K2[TCNE]2. The study shows that the long, multicenter intradimer bond in the π-[TCNE]22-dimer is stronger compared with some hydrogen bonds.