Anion substitution with bismuth (Bi) in III-V semiconductors is an effective method for experimental engineering of the band gap $E_g$ at low Bi concentrations $\left(\le 2\%\right)$, in particular in gallium arsenide (GaAs). The inverse Bi-concentration dependence of $E_g$ has been found to be linear at low concentrations $x$ and dominated by a valence band defect level anticrossing between As and Bi occupied $p$ levels. Predictive models for the valence band hybridization require a first-principle understanding which can be obtained by density functional theory with the main challenges being the proper description of $E_g$ and the spin-orbit coupling. By using an efficient method to include these effects, it is shown here that at high concentrations $E_g$ is modified mainly by a Bi-Bi $p$ orbital interaction and by the large Bi atom-induced strain. In particular, we find that at high concentrations, the Bi-Bi interactions depend strongly on model periodic cluster configurations, which are not captured by tight-binding models. Averaging over various configurations supports the defect level broadening picture. This points to the role of different atomic configurations obtained by varying the experimental growth conditions in engineering arsenide band gaps, in particular for telecommunication laser technology.

The structure and vibrational properties of the metal–organic interface of 1,4,5,8-naphthalene-tetracarboxylic dianhydride (NTCDA) on Ag(111) were analysed using Fourier-transform infrared absorption spectroscopy in conjunction with density functional theory calculations including dispersion forces (PBE-D3).

This paper outlines the current design trends in food packaging, its main environmentally friendly material alternatives, and industrial processing technologies. In this respect, this important product has undergone several evolutions throughout history. Initially acting as a containment device, it has later evolved into a source of information and even a marketing platform for food companies, always with a view to extending shelf life. However, these functionalities are highly dependent on the materials used and their properties. In this respect, plastics have conquered the food packaging market due to their affordability and flexibility. Nevertheless, environmental concerns have arisen due to their impact on the environment, in addition to the introduction of stricter industry regulations and increased consumer environmental awareness. Therefore, this work found that the current design trends in food packaging are toward sustainability, reducing packaging complexity, with easier recycling, and material selection that combines both sustainability and functionality. In the case of bioplastics as a sustainable alternative, there is still room for improvement in their production, with careful consideration of their raw materials. In addition, their technical performance is generally lower, with challenges in barrier properties and processability, which could be addressed with the adoption of Industry 4.0.

High-power lasers can be used to clear a foggy or cloudy atmosphere by exploding and shattering water microdroplets into smaller fragments. The physics of laser–droplet interaction strongly depend on the excitation wavelength and pulse duration, and new techniques with optimized energy requirements that enable lossless long-distance propagation are urgently needed. In this work, a novel and elegant way of water droplet shattering by sub-µJ long-wave infrared ultrashort laser pulses is proposed, making it possible to practically avoid undesirable electron plasma generation in a water droplet and optical breakdown in air. A multiphysics study is performed, which takes into account a hierarchy of physical processes including free carrier plasma kinetics underpinned by a full-vector nonlinear Maxwell solver and the thermomechanical dynamics of pressure waves followed by droplet shattering into smaller fragments described by Navier–Stokes equations. Our results are crucial both for understanding the fundamental nature of water excitation with long-wave infrared radiation and for development of laser applications such as atmospheric communications.

The gas phase decomposition reactions of precursor molecules relevant for metal–organic vapour phase epitaxy (MOVPE) of semiconductor thin films are investigated by computational methods on the density-functional level as well as on the ab initio (MP2, CCSD(T)) level. A comprehensive reaction catalogue of uni- and bimolecular reactions is presented for triethylgallium (TEG) as well as for tert-butylphosphine (TBP) containing thermodynamic data together with transition state energies. From these energies it can be concluded that TEG is decomposed in the gas phase under MOVPE conditions (T = 400–675 °C, p = 0.05 atm) to GaH₃via a series of β-hydride elimination reactions. For elevated temperatures, further decomposition to GaH is thermodynamically accessible. In the case of TBP, the original precursor molecule will be most abundant since all reaction channels exhibit either large barriers or unfavorable thermodynamics. Dispersion-corrected density functional calculations (PBE-D3) provide an accurate description of the reactions investigated in comparison to high level CCSD(T) calculations serving as benchmark values.