Morrisonesbensen9033

Nonlinear optical (NLO) materials have critically important applications in advanced laser technologies. However, achieving a good balance between the mutual competing NLO properties and band gap within one molecular structure remains a great challenge. In this study, two alkaline earth metal fluorinated molybdenum oxide selenite/tellurite, Ba(MoO2F)2(XO3)2 [X = Se (BMFS) and Te (BMFT)], were synthesized through a facile unary substitution BMFS was obtained by partial substitution of oxygen atoms with highly electronegative fluorine in the parent compound BaMo2O5(SeO3)2 (BMS), while BMFT was achieved by further replacing lone-pair Se4+ cations in BMFS with heavier Te4+ cations in the same main group. By partially replacing oxygen with fluorine, BMFS shows a broadened band gap and enhanced second harmonic generation (SHG) response compared to BMS owing to the high electronegativity of fluorine anions and the favorable orientation and alignment of NLO-active [MoO5F]5- and [SeO3]2- groups, which is relatively rare for unary anion substitution. BMFS and BMFT are isostructural and both belong to the polar space group Aba2, featuring a three-dimensional (3D) double-layered framework composed of 2D [MoO4F(XO3)]∞ anionic layers interconnected by divalent barium cations. Both BMFS and BMFT exhibit good optical performance, including large SHG responses (3× and 4× KH2PO4), wide band gaps (3.30 and 3.27 eV) and optical transparency window, and high laser damage thresholds (60× and 53× AgGaS2), demonstrating their potential applications as promising second-order NLO crystals. DFT calculations have elucidated the crucial role of the [MoO5F]5- groups in the enlarged band gaps and enhanced SHG responses in BMFS and BMFT. This work proposes a feasible unary substitution strategy for synthesizing the first polar fluorinated molybdenum oxide selenite/tellurite with synchronously enlarged band gaps and SHG efficiency.Cellulose nanocrystals (CNCs) can spontaneously assemble into chiral nematic films capable of reflecting circularly polarized light in the visible range. As many other photonic materials obtained by bottom-up approaches, CNC films often display defects that greatly impact their visual appearance. Here, we study the optical response of defects in photonic CNC films, coupling optical microscopy with hyperspectral imaging, and we compare it to optical simulations of discontinuous cholesteric structures of increasing complexity. Cross-sectional SEM observations of the film structure guided the choice of simulation parameters and showed excellent agreement with experimental optical patterns. More importantly, it strongly suggests that the last fraction of CNCs to self-assemble, upon solvent evaporation, does not undergo the typical nucleation and growth pathway, but a spinodal decomposition, an alternative self-assembly pathway so far overlooked in cast films and that can have far-reaching consequences on choices of CNC sources and assembly conditions.Three uranyl carboxylates, namely, (UO2)(L1)(H2O)0.5 (1), [(UO2)(L2)(H2O)]·2H2O (2), and [(UO2)(L2)(H2O)]·(CH3CN) (3), were synthesized hydrothermally from 2',3',5',6'-tetramethyl-(1,1'4',1″-terphenyl)-4,4″-dicarboxylic acid (H2L1) and 2',5'-dimethyl-(1,1'4',1″-terphenyl)-3,3″-dicarboxylic acid (H2L2), which are all steric carboxylic acid ligands but vary with the carboxylic acid group position and methyl group number. It is found that compound 1 displays a three-dimensional 8-fold-interpenetrated net with channels running along the c direction. Compounds 2 and 3 are isostructural, and all display two-dimensional-layered crystal structures but contain different guest molecules. The photophysical measurements reveal that compounds 1 and 2, which contain disordered water molecules, are luminescence-quenched, whereas compound 3 containing acetonitrile molecules is luminescent.We established a system for simultaneous measurements of photoelectrochemical (PEC) reaction and photoabsorption in a semiconductor photoelectrode. This system uses a photoacoustic technique and photoelectrodes with a film-thickness gradient that was prepared by electrophoretic deposition of tungsten(VI) oxide particles while pulling up a substrate. The system enabled high-throughput determination of optimum film thickness, and the results showed that irradiation direction has a significant influence on PEC performance for a photoelectrode with a thick film. Furthermore, the mechanism of enhancement of PEC performance by postnecking treatment was discussed.Despite small-molecule surfactants and polymers being widely used as pesticide adjuvants to inhibit droplet bouncing and splashing, they still have intrinsic drawbacks either in the easy wind drift and evaporation, the unfavorable wettability, or the usage of nonrenewable resources. In this paper, we found that upon droplet impacting, 1D nanofibers assembled from natural glycyrrhizic acid (GL) could pin on the rough hydrophobic surface and delay the retraction rate of droplets effectively. Using GL as a tank-mixed adjuvant, the efficiency of glyphosate to control the weed growth was improved significantly in the field experiment, which addressed the dilemmas of current adjuvants elegantly. Our work not only provides a constructive way to overcome droplet bouncing but also prompted us to verify in future if all 1D nanofibers assembled from different small molecules can display similar control efficiencies.As we begin to reach the limits of classical computing, quantum computing has emerged as a technology that has captured the imagination of the scientific world. While for many years, the ability to execute quantum algorithms was only a theoretical possibility, recent advances in hardware mean that quantum computing devices now exist that can carry out quantum computation on a limited scale. Thus, it is now a real possibility, and of central importance at this time, to assess the potential impact of quantum computers on real problems of interest. One of the earliest and most compelling applications for quantum computers is Feynman's idea of simulating quantum systems with many degrees of freedom. learn more Such systems are found across chemistry, physics, and materials science. The particular way in which quantum computing extends classical computing means that one cannot expect arbitrary simulations to be sped up by a quantum computer, thus one must carefully identify areas where quantum advantage may be achieved. In this review, we briefly describe central problems in chemistry and materials science, in areas of electronic structure, quantum statistical mechanics, and quantum dynamics that are of potential interest for solution on a quantum computer.