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Novel spintronic materials combining both magnetism and nontrivial topological electronic structures have attracted increasing attention recently. Here, we systematically studied the doping effects, magnetism, half-metallicity, and topological properties in the family of Fe2-xVxPO5 (x = 0, 0.5, 1, 1.5, 2) compounds. Our results show that Fe2PO5 takes an antiferromagnetic (AFM) ordering with a zero total magnetic moment. Meanwhile, the material hosts a Dirac nodal line and a Weyl nodal line near the Fermi level. V2PO5 is a ferromagnetic (FM) nodal line half-metal with a 100% spin-polarized Weyl nodal line. After doping, we find that Fe1.5V0.5PO5, Fe1V1PO5 and Fe0.5V1.5PO5 all take ferrimagnetic (FiM) ordering, with the Fe and V atoms taking opposite spin directions. Both Fe1.5V0.5PO5 and Fe0.5V1.5PO5 are FiM half-metals. Meanwhile, they show several pairs of fully spin-polarized Weyl points near the Fermi level. Fe1V1PO5 is a FiM semiconductor with different sizes of band gaps in different spin channels. These Fe2-xVxPO5 materials not only provide a good research platform to study the novel properties combining magnetism and nontrivial band topology, but also have promising applications in spintronic applications.Benefitting from their unique structure and physicochemical properties, two-dimensional (2D) materials have aroused tremendous interest from academia and industry, being regarded as an important class of photocatalysts. However, their photocatalytic activities still need further improvement to satisfy the requirement of scale-up production. In this regard, the surface engineering strategy is considered as one of the most effective methods for optimizing their photocatalytic performance. This feature article not only classifies the 2D photocatalysts into layered and non-layered 2D photocatalysts and presents their preferred synthesis methods, but also summarizes the advantages of the surface engineering strategy for boosting the photocatalytic performance of 2D materials from the aspects of light absorption, charge carrier separation and surface active sites. Various surface engineering strategies, such as surface decorating, vacancy engineering, element doping, surface heterojunction construction and regulation of facet-dependent sites, have also been presented as advantages of the surface engineering strategy. Eventually, the challenges and future outlook for optimizing the photocatalytic activities of 2D materials through surface engineering are addressed.Light-enabled, AlCl3-catalyzed regioselective intramolecular nucleophilic cyclization of alkynes using non-nucleophilic alkyls as the nucleophile is reported. Upon photoexcitation, o-alkylphenyl alkynyl ketones can be transferred into (E)-photoenols. Thus, a nucleophilic methylene is formed from the non-nucleophilic alkyl. An AlCl3 catalyst can stabilize the (E)-photoenol intermediate and facilitate further intramolecular nucleophilic cyclization. DFT calculations indicated that the AlCl3-catalyzed cyclization is the regioselectivity determining step.Elastomer, poly(n-butyl methacrylate), coated liquid metal (LM) nanodroplets (EGaIn@PBMA) were successfully fabricated via a facile in situ free radical polymerization method. The as-prepared soft nanoparticles can be directly hot-pressed into nanocomposites which not only exhibited ultra-high stretching flexibility (>400%) but also excellent dielectric properties with remarkably suppressed dielectric loss, showing great promise in the flexible energy-storage field.The photoinduced cycloreversion of oxetanes has been thoroughly investigated in connection with the photorepair of the well-known DNA (6-4) photoproducts. In the present work, the direct photolysis of the two regioisomers arising from the irradiation of benzophenone (BP) and 1,3-dimethylthymine (DMT), namely the head-to-head (HH-1) and head-to-tail (HT-1) oxetane adducts, has been investigated by combining ultrafast spectroscopy and theoretical multiconfigurational quantum chemistry analysis. Both the experimental and computational results agree with the involvement of an excited triplet exciplex 3[BPDMT]* for the photoinduced oxetane cleavage to generate 3BP* and DMT through an adiabatic photochemical reaction. GSK-3 beta pathway The experimental signature of 3[BPDMT]* is the appearance of an absorption band at ca. 400 nm, detected by femtosecond transient absorption spectroscopy. Its formation is markedly regioselective, as it is more efficient and proceeds faster for HH-1 (∼2.8 ps) than for HT-1 (∼6.3 ps). This is in line with the theoretical analysis, which predicts an energy barrier to reach the triplet exciplex for HT-1, in contrast with a less hindered profile for HH-1. Finally, the more favorable adiabatic cycloreversion of HH-1 compared to that of HT-1 is explained by its lower probability to reach the intersystem crossing with the ground state, which would induce a radiationless deactivation process leading either to a starting adduct or to a dissociated BP and DMT.In this perspective article we highlight research opportunities and challenges in probing structural dynamics of molecular systems using X-ray Photon Correlation Spectroscopy (XPCS). The development of new X-ray sources, such as 4th generation storage rings and X-ray free-electron lasers (XFELs), provides promising new insights into molecular motion. Employing XPCS at these sources allows to capture a very broad range of timescales and lengthscales, spanning from femtoseconds to minutes and atomic scales to the mesoscale. Here, we discuss the scientific questions that can be addressed with these novel tools for two prominent examples the dynamics of proteins in biomolecular condensates and the dynamics of supercooled water. Finally, we provide practical tips for designing and estimating feasibility of XPCS experiments as well as on detecting and mitigating radiation damage.In the search for new sources of antimicrobials many researchers have investigated antimicrobial peptides (AMPs) as templates for the design of innovative therapeutics. However, efforts to develop AMPs in this area has been severely hampered by their inherent susceptibility to enzymatic degradation. Given this only a handful of AMPs are currently in clinical trials. Peptide mimetics such as peptoids have emerged as highly promising alternatives to AMPs as they are inherently stable to enzymatic degradation and display potent antimicrobial properties. This feature article highlights the progress that has been made towards the development of novel anti-infective peptoids.