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The Faraday Discussion 'From optical to THz control of materials' was held in London, UK, and online on the 23rd, 24th, and 25th May 2022. The meeting brought together established and early-career scientists, postgraduate students, scientific editors, and industrial researchers in the field of spectroscopy and materials science from over ten different countries interested in exploring the physical properties of materials at ultrafast timescales driven by optical and THz excitations. This conference report provides highlights of this meeting and we give summaries of the presentations including the introductory lecture, all the papers discussed, and the concluding remarks. [ABSTRACT FROM AUTHOR]

Perfluoroalkyl groups containing bicyclo[1.1.1]pentanes (BCPs) are gaining increasing interest in the pharmaceutical industry and materials science; however, the development of an efficient methodology to construct perfluoroalkylated BCPs remains a challenging task. In this paper, we present a metal-free strategy to synthesize 1-perfluoroalkyl-3-heteroaryl bicyclo[1.1.1]pentanes using an electron donor-acceptor (EDA) complex for the perfluoroalkylation of [1.1.1]propellane. After visible light irradiation, the resulting EDA complexes formed by perfluoroalkyl iodide and DBU lead to the generation of perfluoroalkyl radicals. These then sequentially react with highly strained [1.1.1]propellane and various heterocyclic compounds. Mechanistic studies revealed that this method proceeded via a radical chain reaction. This strategy may provide a versatile and sustainable way to obtain 1-perfluoroalkyl-3-heteroaryl bicyclo[1.1.1]pentanes with good functional group tolerance under mild conditions. [ABSTRACT FROM AUTHOR]

The gas-sensing properties of two-dimensional materials have always been a research hotspot in the field of materials science. In this paper, the adsorption mechanism of common toxic gases on monolayer antimony phosphide (SbP), including CO, H2S, NH3, SO2, and NO2, is investigated based on first principles calculation. The results show high adsorption energy and charge transfer between monolayer SbP and NO2, which are −0.876 eV and −0.83 e, respectively. Then, combined with the analysis of electronic properties, we prove that P-orbital hybridization between atoms is the main reason for the high sensitivity and selectivity of monolayer SbP to NO2 gas molecules. In addition, when NO2 coexists with SO2, H2O, and CO2, respectively, the strong interaction between NO2 and SbP is hardly affected. Finally, the results of ab initio molecular dynamics simulation, recovery time, and strain regulation further predict the excellent performance of monolayer SbP in practical applications. Therefore, monolayer SbP is expected to be an excellent sensing material for NO2 detection. [ABSTRACT FROM AUTHOR]

That the boundaries of analysis using XRF spectrometry performed at SR sources continues to be pushed back is evidenced by the nanoscale spatial resolution with near single-atom sensitivity for the most efficiently detected elements in nanobeam applications and high speed 2D/3D imaging capabilities. The 4th generation SR facilities currently under development, such as the ESRF Extremely Brilliant Source (EBS), will be at the forefront of these advances. A clear trend is that SR-XRF spectrometry is increasingly applied with complementary X-ray spectroscopic/imaging techniques to combine spatially resolved elemental information with speciation and structural/morphological imaging. The wide range of applications of scanning (sub)microXRF spectrometry for elemental imaging published in the period covered by this review included biomedical, environmental, materials science and cultural heritage studies. Most applications involved XAS and XRD methods at hard X-ray micro- and nano-probe facilities. Full field microXRF spectrometry has made very promising advances with respect to the optics used. Coded apertures have potential for overcoming the low count rates that often restrict the full potential of laboratory-based full-field setups. The availability of commercial full-field detectors will increase the user community and thereby foster advancement in full field microXRF spectrometry. The TXRF spectrometry of ambient air is becoming more and more sophisticated and the advantages of this micro analytical tool over ICP-MS in terms of short sampling times with high particle size resolution are becoming ever more apparent. For example, the optimal sampling time for aerosols for TXRF analysis was well below 12 hours, whereas that for ICP-MS analysis was about 24 hours. High-quality grazing incidence XRF analysis in the laboratory has become more feasible with the development of prototype TXRF instrumentation and the availability of commercial XRD setups with energy dispersive detectors. Portable XRF spectrometry has undergone significant technological improvements in recent years and is now applied in a wide range of applications. This is reflected in a significant number of valuable review papers dealing with different aspects of the portable XRF technique. The growth in the use of macroXRF scanning systems in cultural heritage investigations has required development of new software and methodologies for efficient handling of the huge data files generated. In several contributions the possibilities of a new scanning station equipped with real time macroXRF spectrometry was demonstrated. [ABSTRACT FROM AUTHOR]

Density functional theory (DFT) is the most widely-used electronic structure approximation across chemistry, physics, and materials science. Every year, thousands of papers report hybrid DFT simulations of chemical structures, mechanisms, and spectra. Unfortunately, hybrid DFT's accuracy is ultimately limited by tradeoffs between over-delocalization and under-binding. This review summarizes these tradeoffs, and introduces six modern attempts to go beyond them while maintaining hybrid DFT's relatively low computational cost: DFT+U, self-interaction corrections, localized orbital scaling corrections, local hybrid functionals, real-space nondynamical correlation, and our rung-3.5 approach. The review concludes with practical suggestions for DFT users to identify and mitigate these tradeoffs' impact on their simulations. [ABSTRACT FROM AUTHOR]