Mechanics and physics of a glass/particles photonic sponge.

A glass containing mechanoluminescent crystalline particles behaves as a photonic sponge: that is to say it fills up with trapped electrons when exposed to UV light, and it emits light when submitted to a mechanical loading, similar to a sponge soaked with water that is wringed under mechanical action! A major finding of the present study is that the elasto-mechanoluminescence effect showing up on unloading is governed by the deviatoric part of the applied stress (no effect under hydrostatic pressure). Furthermore, the structural source for this phenomenon was elucidated by a detailed density functional theory analysis of the e energetics at the possible oxygen vacancy sites within the crystalline phase. Both the e trapping and detrapping processes under load could be explained.

Author Correction: Layer-dependent quantum cooperation of electron and hole states in the anomalous semimetal WTe.

This Article contains an error in the spelling of the author A. Yazdani, which is incorrectly given as A. Yadzani.

Photoluminescence, infrared, and Raman spectra of co-doped Si nanoparticles from first principles.

Co-doped silicon nanoparticles (NPs) are promising for the realization of novel biological and optoelectronic applications. Despite the scientific and technological interest, the structure of heavily co-doped Si NPs is still not very well understood. By means of first principles simulations, various spectroscopic quantities can be computed and compared to the corresponding experimental data.

Microscopic origin of chiral shape induction in achiral crystals.

In biomineralization, inorganic materials are formed with remarkable control of the shape and morphology. Chirality, as present in the biomolecular world, is therefore also common for biominerals. Biomacromolecules, like proteins and polysaccharides, are in direct contact with the mineral phase and act as modifiers during nucleation and crystal growth.