Major-league magnetostriction: Magnetoelectric materials polarize in response to either electric or magnetic fields, making them attractive for data-storage applications. Long et al. discovered a ytterbium-based molecular magnetoelectric material with high magnetoelectric coupling (see the Perspective by Zhou and Han). An applied magnetic field strains the material, which changes its electrical properties. The required field is much lower than other magnetoelectric materials, and this work highlights the potential for using molecular materials in devices. Science , this issue p. 671 ; see also p. 627

A new approach to an efficient and selective extraction of Cs⁺ ions from water, sea water enriched with Cs⁺ and a radioactive solution simulating the effluents of the Fukushima reactors (¹³⁷Cs, 29 kBq L⁻¹) was developed by using porous silica- or glass-based nanocomposites containing Prussian blue type nanoparticles, Co²⁺/[Fe(CN)₆]³⁻, with sizes below 10 nm. A particular emphasis is given on the kinetics of cesium sorption fitted by using the classical reaction order model as well as a diffusion model in order to better understand the sorption mechanism. Compared to the amount of Co²⁺/[Fe(CN)₆]³⁻ nanoparticles, the sorption capacities of studied nanocomposites are more than three times higher than the ones observed for the respective bulk materials. These nanocomposites present a high selectivity to Cs⁺ and extract it in trace amounts.

A new heterodinuclear [Zn(L)Dy]³⁺ complex, with L being a compartmental Schiff base ligand, exhibits the characteristic Dy³⁺ luminescence associated with a single-ion field induced slow relaxation of the magnetisation. This complex may be considered as one of the rare examples of a bifunctional luminescent single-ion magnet.

We analyzed the size effect on a first-order spin transition governed by elastic interactions. This study was performed in the framework of a nonextensive thermodynamic core-shell model. When decreasing the particle size, differences in surface energies between the two phases lead to the shrinking of the thermal hysteresis width, the lowering of the transition temperature, and the increase of residual fractions at low temperature, in good agreement with recent experimental observations on spin transition nanomaterials. On the other hand, a modification of the particle-matrix interface may allow for the existence of the hysteresis loop even at very low sizes. In addition, an unexpected reopening of the hysteresis, when the size decreases, is also possible due to the hardening of the nanoparticles at very small sizes, which we deduced from the size dependence of the Debye temperature of a series of coordination nanoparticles.