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The surface optical (SO) phonon replica in photoluminescence (PL) spectroscopy of nitride nanowires (NWs) was theoretically investigated in this study. The dispersive relationships of SO phonon mode in anisotropic wurtzite (WZ) and isotropic zinc-blende (ZB) crystal structure NWs with circular and square cross sections (CSs) were derived within the framework of the dielectric continuum model. Based on the energy and momentum conservation laws, a constraint relationship between the frequency and wave-number was constructed for SO phonon-assisted excitonic PL spectra in the NW structure. By combining the dispersive and constraint relationships, the frequency and wave-number of the SO phonon replica in the PL spectra could be determined. The WZ and ZB crystal structures of nitride semiconductor were considered. The influences of surface factors including the CS shape, dielectric medium, and environment temperature on the frequency and photon wavelength of the band-edge emission of the SO phonon replica were studied in detail. Numerical results reveal that the crystal structure, surface factors, and environment temperature greatly affect the frequency and photon wavelength of the band-edge emission of the SO phonon replica. The calculated results for the photon wavelength agree well with the experimental values of the SO phonon replica in AlN NWs. The results of the dielectric effect obtained here are also supported by previous experimental and theoretical results for nitrides and other semiconductor NWs. The present theoretical scheme and numerical results can be used to analyze and design the SO phonon replica in PL spectra of nanostructures. [ABSTRACT FROM AUTHOR]

Two ionic hydrogen‐bonded organic frameworks (iHOFs) assembled from 4‐cyano‐N‐(4‐cyanobenzyl)pyridinium, have been crystallized with Br− and antimony(III) pentabromide, [SbBr5]2−, as counter‐ions and characterized. These are 4‐cyano‐N‐(4‐cyanobenzyl)pyridinium bromide, C14H10N3+·Br−, and bis[4‐cyano‐N‐(4‐cyanobenzyl)pyridinium] antimony(III) pentabromide, (C14H10N3)2[SbBr5]. The CH...NC interactions induced by templating anions construct disparate frameworks. Hirshfeld surface analysis indicated that these crystals exhibit two types of hydrogen‐bonding interactions, specifically CH...NC and CH...Br. Consecutive reverse‐parallel CH...NC hydrogen‐bonding interactions in these crystals induced the formation of a large number of CH...NC bonds which exhibit both cis and trans configurations. [ABSTRACT FROM AUTHOR]

Starting from [Mn(C5H4Br)(PPh3)(CO)2] (1a), the cymantrenyl thioethers [Mn(C5H4SMe)(PPh3)(CO)2] (1b) and [Mn{C5H4–nBr(SMe)n}(PPh3)(CO)2] (n = 1 for compound 2, n = 2 for 3 and n = 3 for 4) were obtained, using either n‐butyllithium (n‐BuLi), lithium diisopropylamide (LDA) or lithium tetramethylpiperidide (LiTMP) as base, followed by electrophilic quenching with MeSSMe. Stepwise consecutive reaction of [Mn(C5Br5)(PPh3)(CO)2] with n‐BuLi and MeSSMe led finally to [Mn{C5(SMe)5}(PPh3)(CO)2] (11), only the fifth complex to be reported containing a perthiolated cyclopentadienyl ring. The molecular and crystal structures of 1b, 3, 4 and 11 were determined and were studied for the occurrence of S...S and S...Br interactions. It turned out that although some interactions of this type occurred, they were of minor importance for the arrangement of the molecules in the crystal. [ABSTRACT FROM AUTHOR]

Starting from [Mn(C5H4Br)(PPh3)(CO)2] (1a), the cymantrenyl thioethers [Mn(C5H4SMe)(PPh3)(CO)2] (1b) and [Mn{C5H4–nBr(SMe)n}(PPh3)(CO)2] (n = 1 for compound 2, n = 2 for 3 and n = 3 for 4) were obtained, using either n‐butyllithium (n‐BuLi), lithium diisopropylamide (LDA) or lithium tetramethylpiperidide (LiTMP) as base, followed by electrophilic quenching with MeSSMe. Stepwise consecutive reaction of [Mn(C5Br5)(PPh3)(CO)2] with n‐BuLi and MeSSMe led finally to [Mn{C5(SMe)5}(PPh3)(CO)2] (11), only the fifth complex to be reported containing a perthiolated cyclopentadienyl ring. The molecular and crystal structures of 1b, 3, 4 and 11 were determined and were studied for the occurrence of S...S and S...Br interactions. It turned out that although some interactions of this type occurred, they were of minor importance for the arrangement of the molecules in the crystal. [ABSTRACT FROM AUTHOR]

Direct recycling is a key technology for enabling a circular economy of spent lithium ion batteries (LIBs). For cathode active materials (CAMs), it is regarded as the tightest closed‐loop and most efficient approach among current recycling techniques as it simply proceeds via re‐lithiation and reconstruction of aged CAMs instead of separating them into elemental components. In this work, spent, i.e., morphologically and structurally decomposed CAM based on LiNi0.83Co0.12Mn0.05O2 (NCM‐831205) is restored by mimicking conditions of original CAM synthesis. After evaluating and optimizing the high‐temperature duration for CAM restoration and subsequent washing procedure, the recycled CAM is shown to maintain poly‐crystallinity and tap density, successfully recover specific surface area, lithium content, crystal structure in surface and bulk, while, however, only partly the original secondary particle size and shape. Though, comparable in initial 100 charge/discharge cycles with pristine CAM in lithium ion‐cells, the subsequent increase in resistance and capacity fading remains a challenge. High temperature during recycling can be regarded as a key challenge on material level, as it not only promotes detrimental surface carbonate species from residual carbon black but also enhances cation disorder and micro‐/nanoscopic porosity through oxygen release, likely in de‐lithiated, thus less thermally stable regions of cycled NCM. [ABSTRACT FROM AUTHOR]

Hysteresis related to first-order phase transformation in shape memory alloys, which is the macroscopic manifestation of energy dissipation, is detrimental to the precise control of actuation and causes structural and functional fatigue of components. It is of vital importance to explore high-performance shape memory alloys with low stress-hysteresis, large superelasticity, and wide temperature range operation in practical applications. Here, we have developed a Ni-Mn-Fe-In shape memory microwire, exhibiting an ultra-low stress-hysteresis and huge tensile superelasticity in a wide temperature range. The microwire shows a smooth surface and a single crystal structure (with ⟨001⟩A-oriented along the axial direction of microwire), and the microstructure of the microwire contains austenite matrix and sparsely distributed precipitates with an average size of 20–80 nm, all of which may be beneficial to obtain low hysteresis and large strains in the microwire. As a result, the microwire exhibits a minimum stress-hysteresis of as low as 8.5 MPa (with overall strain of 15.3%) and corresponding energy dissipation as low as 1.44 MJ/m3. The microwire always shows a low stress-hysteresis (less than 24 MPa) and low energy dissipation (less than 2.86 MJ/m3) above room temperature. The microwire shows a huge superelasticity with recoverable strains higher than 15% in the wide temperature range from 218 to 418 K. Together with the advantages of easy fabrication and no post-processing required, this microwire shows a tremendous potential for cyclic actuators and energy conversion devices under multi-field coupling. [ABSTRACT FROM AUTHOR]

3,4-Dinitrofurazanfuroxan (DNTF) is widely used in fusion-cast-based explosive carriers owing to its low melting point, high energy, and excellent stability. To reduce the susceptibility of DNTF and improve the thermal properties, core–shell composites (DNTF@PDA@HTPB) were synthesized using the oxidative self-polymerization reaction of dopamine. The results showed that hydroxyl-terminated polybutadiene (HTPB) was tightly coated on the surface of DNTF@PDA crystals, and the crystal structure of the high-energy crystals did not experience any significant changes during the encapsulation process. Compared with the raw DNTF, the thermal decomposition of DNTF in the DNTF@PDA and DNTF@PDA are delayed by 13.3℃ and 17.1℃, respectively. This phenomenon indicates that the thermal stability of DNTF@PDA and DNTF@PDA@HTPB composites is improved. The ignition speed of DNTF@PDA@HTPB is faster, and the flame activity is more vigorous. Meanwhile, the friction susceptibility of DNTF@PDA@HTPB is reduced by 44% compared to DNTF, and the impact susceptibility is significantly reduced by 75%. This study provides a new idea to improve fused-cast explosives' structure and combustion performance. [ABSTRACT FROM AUTHOR]

Reaction of thorium(IV) nitrate with 2-[(4-phenyl-1H-1,2,3-triazol-1-yl)meth­yl]pyridine (L) yielded (LH)2[Th(NO3)6] or (C14H13N4)2[Th(NO3)6] (1), instead of the expected mixed-ligand complex [Th(NO3)4L2], which was detected in the mass spectrum of 1. In the structure, the [Th(NO3)6]2- anions display an icosa­hedral coordination geometry and are connected by LH+ cations through C--H...O hydrogen bonds. The LH+ cations inter­act via N--H...N hydrogen bonds. Hirshfeld surface analysis indicates that the most important inter­actions are O...H/H...O hydrogen-bonding inter­actions, which represent a 55.2% contribution. [ABSTRACT FROM AUTHOR]

This article explores the surface architecture formation on layered A3B6 semiconductors, such as In4Se3, InSe, and InTe, focusing on kinetics of surface roughness parameters, such as RMS, skewness and kurtosis, and power spectral density (PSD) under indium deposition studied through large-scale 1 × 1 µm2 and 150 × 150 nm2 scanning tunneling microscopy (STM) images analysis. Our findings reveal common kinetics of surface parameters across different crystals, suggesting fundamental similarities in their interface kinetics. Particularly, PSD analysis elucidates the role of low-frequency spatial structures, underscoring their significance in surface roughness kinetics to some extent independent of the specific layered crystal surface structure. [ABSTRACT FROM AUTHOR]

The uncontrollable dendrite growth on the Zn metal anode severely deteriorates the capacity and cycling stability of aqueous zinc–ion batteries (AZIBs), thereby retarding their practical application. In this work, through the combination of surface chemistry and crystal structure regulation, a duplex route of plasma sputtering and mechanical stretching is proposed to remove surface passivation layer and increase surface crystal defect (dislocations and textures) of Zn metal anode itself. Plasma sputtering can almost completely remove the surface passivation layer, ensuring a uniform Zn2+ flux at the interface, which is conducive to uniform nucleation. Mechanical stretching can increase the surface dislocation density and (002) texture, the former can reduce Zn2+ nucleation barrier, while the latter can guide Zn to grow parallel to the surface, inhibiting the growth of dendrites. Consequently, the as‐fabricated symmetrical cells exhibit stable and long lifespan (3560 h at 0.5 mA cm−2 for 0.5 mA h cm−2). The assembled full cells with α‐MnO2 cathode deliver a nearly 100% average coulombic efficiency even after 1000 cycles at 5 A g−1. Coupling a surface chemistry regulation with crystal structure control will be enlightening for solve the issues of metallic anodes in advanced metallic‐based batteries. [ABSTRACT FROM AUTHOR]

A series of novel substituted antipyrine attached bis-triazoles 7(a-h) were synthesized via coupling followed by click chemistry reaction. Their structure was established by means of physico-chemical spectral studies and a single-crystal X-ray diffraction analysis (7c and 7f). X-ray diffraction results exhibited that 7c and 7f were crystallized in triclinic space group where a = 9.352(3) Å, b = 11.002(3) Å, c = 14.616(4) Å and also revealed that the bis-triazole ring formed by two terminal alkyne groups joined with substituted azides (6a-h). The Hirshfeld surface analysis of the crystal surface shows that the most contributions for H⋯H/H⋯H, C⋯H/H⋯C, N⋯H/H⋯N, O⋯H/H⋯O, and C⋯C interactions. Breast adenocarcinoma cell line used test the compounds anticancer effects by MTT assay. Compound 7f was found to be most promising scaffold, exhibiting a anticancer effect near to standard imatinib (IC50 at 25.03±0.01 mg). The results exhibited that these analogues could be lead compounds in search for new effective anticancer agents. [ABSTRACT FROM AUTHOR]

The crystal structure of superprotonic conductor caesium hydrogen sulfate phosphate [Cs4(HSO4)3(H2PO4)] have been analyzed using neutron diffraction methods. Additionally, its structure and surface layers have been investigated using atomic force microscopy. From the diffraction data obtained, Fourier syntheses of neutron scattering densities were calculated, and the localization of hydrogen atoms and the parameters of three types of hydrogen bonds in the crystal structure were accurately determined. Correlation of surface characteristics of samples obtained by atomic force microscopy with their crystal structure is shown. [ABSTRACT FROM AUTHOR]

The influence of pulsed helium plasma irradiation, with a 10 μs duration and a surface energy load of 0.2 MJ m-2, on the elemental and phase composition, surface morphology and crystal structure of thin-film heterosystems based on CdS/CdTe was studied. The cadmium sulphide and cadmium telluride layers were deposited by condensation via a hot wall method onto a glass substrate covered with an FTO layer. It was found that after one pulse, the device structure remains in working condition. An increase in the irradiation dose leads to surface sputtering, the formation of through pores 0.5 – 2 μm in size, and a microcracks network with two characteristic scales. One crack network is formed in the glass substrate, and the second network is formed with cracks in the CdTe film. It is shown that the thermal effect of plasma stimulates the diffusion of sulphur; as a result, the proportion of CdTe1-xSx solid solutions formed in the process of obtaining the CdS/CdTe heterosystem increases. In addition, the sulphur content increases in these solid solutions, which leads to their decomposition with the separation of the CdS1-yTey solid solution phase. These solid solutions migrate to the CdTe surface through cracks and are observed as separate crystals. [ABSTRACT FROM AUTHOR]

A new ε-polymorph of 4,4,5,5-tetramethyl-2-(4-nitrophenyl)-4,5-dihydro-1H-imidazol-3-oxide-1-oxyl is prepared and characterized by single-crystal XRD. The arrays of XRD data have been accumulated and the structures of known α–γ-polymorphs of this paramagnetic are solved under the same conditions. The Hirshfeld surfaces of the crystal structures of the studied polymorphs are analyzed qualitatively and quantitatively. It is shown that the known α–δ-polymorphs contain a supramolecular associate in the form of a centrosymmetric dimer whose molecules are connected by C–H⋯O hydrogen bonds. At the same time, only the ε-polymorph contains π-bonded infinite stacks of nitrophenyl substituents, which in turn determine the formation of short distances between oxygen atoms of nitroxide groups (3.508(2) Å and 3.627(2) Å). [ABSTRACT FROM AUTHOR]

The title molecule, [Fe2(C5H5)2(C23H17ClN2)]⋅C3H7NO, is twisted end to end and the central N/C/N unit is disordered. In the crystal, several C--H…π(ring) interactions lead to the formation of layers, which are connected by further C--H…π(ring) interactions. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H…H (60.2%) and H… C/C…H (27.0%) interactions. Hydrogen bonding, C--H…π(ring) interactions and van der Waals interactions dominate the crystal packing. [ABSTRACT FROM AUTHOR]

The in­do­line portion of the title mol­ecule, C16H13NO2, is planar. In the crystal, a layer structure is generated by C--H...O hydrogen bonds and C--H...π(ring), π-stacking and C=O...π(ring) inter­actions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (43.0%), H...C/C...H (25.0%) and H...O/O...H (22.8%) inter­actions. Hydrogen bonding and van der Waals inter­actions are the dominant inter­actions in the crystal packing. The volume of the crystal voids and the percentage of free space were calculated to be 120.52ų and 9.64%, respectively, showing that there is no large cavity in the crystal packing. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated by the dispersion energy contributions in the title compound. Moreover, the DFT-optimized structure at the B3LYP/6-311G(d, p) level is compared with the experimentally determined mol­ecular structure in the solid state. [ABSTRACT FROM AUTHOR]

This study investigates the catalytic oxidation of acetone by different crystal phases of MnO2 prepared via different methods. Compared with β-MnO2 and γ-MnO2, α-MnO2 exhibited superior catalytic activity. Moreover, as replacements for traditional hydrothermal methods and air calcination, the use of microwave hydrothermal methods and N2 calcination significantly enhanced the catalytic performance of the MnO2 catalyst. The optimal catalyst, MnO2-WN (α-MnO2 synthesized via microwave hydrothermal method and N2 calcination), converted 100% of 100 ppm acetone below 150 °C, with the CO2 yields reaching 100%. Further, the stability of the catalyst and its potential for other volatile organic compounds (VOCs) were also determined. The experimental data demonstrated that its outstanding activity primarily stemmed from the improved preparation method, enhancing the specific surface area of the catalyst, optimizing the pore structure, improving the redox performance, and generating more acidic sites and active oxygen species, thereby creating a synergistic effect. Finally, the reaction pathway of acetone oxidation on the catalyst surface has been explored. This work provides a new perspective for developing economically efficient MnOx catalysts for removing VOCs. [ABSTRACT FROM AUTHOR]

The title mol­ecule, C29H44N8O, adopts a conformation resembling a two-bladed fan with the octyl chains largely in fully extended conformations. In the crystal, C—HO hydrogen bonds form chains of mol­ecules extending along the b-axis direction, which are linked by weak C—HN hydrogen bonds and C—Hπ inter­actions to generate a three-dimensional network. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from HH (68.3%), HN/NH (15.7%) and HC/CH (10.4%) inter­actions. [ABSTRACT FROM AUTHOR]

Tb3+-ion-doped metal phosphates (YPO4, LaPO4, CePO4 and GdPO4) nanoparticles (NPs) were synthesized by a urea-supported thermal decomposition method. A comparative analysis was presented to inspect the influence of the host lattice on crystal structure, optical and luminescent properties of the doped Tb3+ ion. X-ray diffraction (XRD) results show the rhabdophane-type hexagonal phase of all lanthanide phosphate (LnPO4) NPs with an average particles size 12.8, 14.9, 18 and 19.5 nm for the YPO4:Tb, LaPO4:Ce/Tb, CePO4:Tb and GdPO4:Tb NPs, respectively. Fourier transforms infrared (FTIR) spectra illustrated the characteristics of crystal and surface build phosphate (PO43–) ion and hydroxyl (OH) vibrational modes, respectively. Absorption spectra were measured to determine the aqueous dispersibility, colloidal stability and charge transfer absorption transitions of the host and guest ions. The absorption edge and bandgap energies were greatly affected in Ce3+-ion-containing NPs because of the high absorbance in the visible region. Upon irradiation of all samples from the similar ultraviolet range 368 nm, the emission efficiency of the 5D4→7F5 of the YPO4:Tb NPs was the least, whereas LaPO4:Ce/Tb NPs exhibited the largest emission and excitation efficiency, because of the proficient energy transfer amid the co-doped absorber Ce3+ and emitter Tb3+ ions. These observed findings are highly beneficial in the development of the most efficient photonic-based material for their multipurpose uses. [ABSTRACT FROM AUTHOR]

In the title molecule, C8H7NO3S, the nitrogen atom has a planar environment, and the thiazine ring exhibits a screw-boat conformation. In the crystal, corrugated layers of molecules parallel to the ab plane are formed by N--H⋯O and C--H⋯O hydrogen bonds together with C--H⋯π(ring) and S=O⋯π(ring) interactions. The layers are connected by additional C--H⋯O hydrogen bonds and πstacking interactions. Hirshfeld surface analysis indicates that the most important contributions for the crystal packing are from H⋯O/O⋯H (49.4%), H⋯H (23.0%) and H⋯C/C⋯H (14.1%) interactions. The volume of the crystal voids and the percentage of free space were calculated as 75.4 Å 3 and 9.3%. Density functional theory (DFT) computations revealed N--H⋯O and C--H⋯O hydrogen-bonding energies of 43.3, 34.7 and 34.4 kJ mol-1, respectively. Evaluation of the electrostatic, dispersion and total energy frameworks indicate that the stabilization is dominated via the electrostatic energy contribution. Moreover, the DFT-optimized structure at the B3LYP/ 6-311 G(d,p) level is compared with the experimentally determined molecular structure in the solid state. The HOMO--LUMO behaviour was elucidated to determine the energy gap. [ABSTRACT FROM AUTHOR]

A series of halogenated podands (P1–P8) have been synthesized from 1,3,5-tris(bromomethyl)mesitylene and halogen-substituted phenols to study the structure-directing roles of C–H hydrogen bonds and halogen bonds in the formation of self-assembled supramolecular frameworks. The ethereal podands are suitable for the study of C–H hydrogen bonds in the crystalline state due to the presence of three different types of C–H donors, such as methyl, methylene, and aromatic –CH groups, and three different types of acceptors such as ethereal oxygen, halogens, and aromatic rings. Single crystal X-ray structures of three halophenyl-functionalized podands (P2, P3 and P4) and a cyanophenyl-functionalized podand (P9) were determined at room temperature (298 K), and detailed Hirshfeld surface analysis of the crystal structures was performed to quantify the close contact contributions (in %) from different types of non-covalent interactions involved in the self-assembly of podands. The crystal structures of the halophenyl-functionalized podands (P2, P3, and P4) showed self-assembly primarily via intermolecular C–H⋯O, C–H⋯π, and halogen bonding interactions. Hirshfeld surface analysis of the crystal structures revealed significantly higher contributions from H⋯C and H⋯X (X = halogen) close contacts in comparison to H⋯O and X⋯C close contacts in 2D-fingerprint plots. The self-assembly of the cyanophenyl-functionalized podand (P9) was largely governed by intermolecular C–H⋯O and C–H⋯N interactions. The podand crystals showed relatively high thermal stability in thermogravimetry analysis (250–290 °C), which can be attributed to the hydrogen and halogen bond assisted formation of 3D supramolecular frameworks. 19F-NMR spectra of tetraethylammonium fluoride in the presence of an equivalent amount of tris(2-halophenoxymethyl)mesitylene podand (P5 or P6) showed a downfield shift of the fluoride signal (Δδ 3.2 ppm) indicating C–X⋯F− halogen bonding in solution. Further, 19F-NMR spectra of hydrogen bifluoride (HF2−) in the presence of P5 or P6 showed a large upfield shift of ≈21–22 ppm suggesting C–X⋯F−⋯H–F halogen bonding in solution. [ABSTRACT FROM AUTHOR]

In the title compound, C16H13N7O2, the 3,5-dimethylphenyl and 4-nitrophenyl rings are inclined to the central 2H-1,2,3-triazole ring by 1.80 (7) and 1.79 (7)°, respectively, and to one another by 2.16 (7)°. In the crystal, the molecules are linked by C--H• • •N hydrogen bonds and π--π stacking interactions [centroid-to-centroid distances = 3.7295 (9) and 3.7971 (9) A°], forming ribbons along the baxis direction. These ribbons are connected to each other by weak van derWaals interactions and the stability of the crystal structure is ensured. A Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from H• • •H (31.5%), N• • •H/H• • •N (19.2%), O• • •H/H• • •O (14.5%), N• • •C/C• • •C (10.9%) and C• • •H/H• • •C (10.2%) contacts. [ABSTRACT FROM AUTHOR]

A biologically promising new molecule, 3-(benzylthio)-4-hydroxy-2H-chromen-2-one has been synthesized following visible light-induced protocol in the presence of singlet molecular oxygen. Its detailed spectral properties and X-ray crystal structure are studied. The crystal structure is solved by direct method and refined to a final R value of 0.0701. The crystal structure is stabilized by an elaborate system of hydrogen bonds along with π–π and Van der Waal's forces to form supramolecular structures. 3D Hirshfeld surfaces and allied 2D fingerprint plots are analyzed for non-covalent interactions. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (38.2%) and C···H/H···C (22.4%) interactions. Energy framework analysis allowed us to quantify different contributions to the overall energy. Theoretical (DFT) studies on the molecular structure, Mulliken charges, HOMO, LUMO, MESP surfaces have been performed at B3LYP/6-311 + G(d,p) level of theory. The molecular docking studies are performed to get insights into the inhibition nature of this molecule against CDKS protein and for searching new anticancer agents. Pharmacological analysis was carried out in-order to check the bioactive nature of synthesized compound. [ABSTRACT FROM AUTHOR]

The specular reflection of X rays from multilayer crystal structures on the surface of a single crystal under conditions of grazing noncoplanar diffraction is considered. Recurrent relations of a new type are obtained. A high sensitivity of the angular dependence of the specular reflection intensity in the diffraction region to the thickness and number of layers, their deformation, and degree of amorphization is shown. [ABSTRACT FROM AUTHOR]

The 3-(cyclohexylthio)-4-hydroxy-6-methyl-2H-chromen-2-one (mf. C16H18O3S), a biologically relevant new version of organo-sulfur compounds, has been synthesized Its detailed spectral properties and X-ray crystal structure are studied. The crystal structure was solved by direct method and refined by full matrix least squares procedure to final R value of 0.0468. The crystal structure is stabilized by elaborate system of O-H···O, C-H···O, O-H···S hydrogen bonds to form supramolecular structures. 3D Hirshfeld surfaces and allied 2D fingerprint plots were analyzed for molecular interactions. The Hirshfeld surface analysis of the crystal structure indicates H...H and C···H/H···C interactions as the most important contributors to the crystal packing. Theoretical (DFT) studies on the molecular structure, HOMO, LUMO, MESP surfaces have been performed at B3LYP/6-311 + G(d,p) level of theory. The molecular docking studies have been performed to get insights into the inhibition nature of this molecule against CDKS protein, and search for new anticancer agents. Pharmacological analysis was carried out inorder to check the bioactive nature of the synthesized compound. [ABSTRACT FROM AUTHOR]

The connection between the peak of density of electronic states at ~ 0.4 eV below the Fermi level and the localization of charge carriers at compression of the height of CuO5 pyramids has been found by a comparison of experimental angle-resolved photoemission spectra data for Y0.9Ca0.1Ba2Cu3O6.8 single crystal and calculations of the electronic structure in a framework of the density functional theory. Both experiment and calculation are performed using 34.6 and 90.2 eV photon energy. The excitation energy does not have any noticeable influence on the peak of density of electronic states. Crystal structure distortions on the crystal surface result in observation of localized electronic states below the temperature of superconducting transition. [ABSTRACT FROM AUTHOR]

A dual-channel sensor was proposed by further processing a gap on the D-shaped surface of a photonic crystal fiber (PCF). The simultaneous and independent measurement for refractive index (RI) and temperature was theoretically demonstrated. On the dual-channel surfaces, the Ag films were elaborated to improve the sensing performance for RI based on surface plasmon resonance (SPR) effect. The sensing performance of the temperature channel was improved by further-overlaying the polydimethylsiloxane (PDMS) film. Furthermore, the TiO2 film was introduced to protect the silver away from oxidation and optimized the sensing performance. When the thickness of Ag film is 45 nm and the thickness of TiO2 film is 13 nm, the highest sensitivities of RI and temperature were respectively obtained as 6700 nm/RIU and − 21 nm/°C. [ABSTRACT FROM AUTHOR]

Background. To decompose water, electrocatalysts based on expensive Pt, Ir are used. However, there is an alternative - catalysts from compounds of d-elements: Fe, Co, Ni, Cu. Purpose. Study of structural morphology features of Ni-Co-P bimetallic phosphide.. Methodology. The synthesis of Ni-Co-P was carried out by a one-stage hydrothermal method, in air. The structure of the sample was studied by electron microscopy (SEM), energy-dispersive spectroscopy, and X-ray diffractometry. Originality. It was revealed that the synthesized Ni-Co-P has a pronounced crystal structure of the compounds Ni2P4O12 (59%), NiP2O7 (37%) and NiCoP (4%). Findings. The synthesis of Ni-Co-P was carried out. The phase composition, morphology of the surface and crystal structure, the nature of the distribution of elements over the volume of Ni-Co-P bimetallic phosphide were studied by physicochemical methods of analysis. [ABSTRACT FROM AUTHOR]

A high-throughput approach to determine the equilibrium shape of a crystal by brute force is impractical due to the vast number of density functional theory (DFT) calculations required along just a single crystallographic direction. We propose a screening method that allows the bypass of performing DFT calculations for each candidate surface. Using a series of physically-motivated simplifications, we are able to consider the relative surface energy of each of the large number of candidate surfaces required to solve the surface energy minimization problem in 3 dimensions. Application of this technique to calculate the surface energy landscapes of a set of well-known crystal structures demonstrates high accuracy in the prediction of stable planes and validates its potential as a valuable tool in ab initio determination of equilibrium crystal shapes. [ABSTRACT FROM AUTHOR]

• A quasi-single-crystal PbO 2 is successfully synthesized by hydrothermal method. • The oriented exposed surfaces are identified as (110) and (101) facets. • The quasi-single-crystal PbO 2 is more conducive to electrochemical ozone production. • The PbO 2 (110) facet is thermodynamically more favorable in the presence of high PVP concentration. The crystal facet of PbO 2 has been proved to be a key factor affecting its electrochemical ozone production (EOP) performance. However, PbO 2 with smooth and uniform crystal surface and single-crystal nature, which is the basis and prerequisite for PbO 2 crystal facet engineering, has not yet been reported. In this study, by adding polyvinylpyrrolidone (PVP) as a facet modifier during the hydrothermal synthesis, a quasi-single-crystal PbO 2 (PVP:Pb(CH 3 COO) 2 ·3H 2 O=48:100, PVP-48) with (110) and (101) exposed facets was successfully synthesized. Compared with commercial PbO 2 prepared by electrochemical deposition, PVP-48 exhibits excellent electrochemical catalytic activity due to its special crystal structure, and achieves the highest current efficiency of 11.9 % at a current density of 0.83 A/cm2. Further calculations show that PVP prefers to adsorb onto the (110) facet of the lead dioxide and reduces its surface energy, thereby exposing the (110) facet more readily. This work demonstrates the importance of PbO 2 facets composition and provides new ideas for further controllable synthesis of PbO 2 with specific facet structure and higher EOP efficiency. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel acylhydrazone based molecule was designed and synthesized that exhibit bright solid state luminescence. • The crystals exhibit multi-stimuli responsive property such as, mechanochromic, thermochromic and vapochromic luminescence switching. • The crystals display fascinating macroscopic surface cracking, movements when 365 nm or 405 nm light is illuminated on the crystal surface. • The examples of such single molecular material that have capability to respond to multiple stimuli is extremely rare. In this manuscript, we report a novel diphenylamine-acylhydrazone based compound namely (E)-N'-(4-(diphenylamino)benzylidene)-4-hydroxybenzohydrazide (DPAhydrzOH) which showed multi-stimuli responsive behavior by displaying pronounced mechanochromic luminescence (MCL), thermochromic luminescence and photomechanical effect in solid state. Single crystal structure of the compound revealed that the molecule is tied with different types of H-bonding interactions. Detailed mechanistic study suggests that the MCL switching in solid crystal is rooted to the shear pressure induced structural rearrangement. The captivating photomechanical effect in the crystal was expressed in the form of cracking, small movement under 365 nm light due to photoinduced trans to cis isomerization in solid state. [ABSTRACT FROM AUTHOR]

This study investigates how variations in substrate temperatures and deposition rates during pulsed laser deposition on Nb-doped SrTiO 3 substrates affect the crystallinity, and consequently, the ferroelectric and piezoelectric properties of SrBi 2 Ta 2 O 9 (SBT) thin films. The SBT thin film developed at 850 °C with a deposition rate of 0.34 nm/pulse showed lower remanent polarization and piezoelectric coefficients, a result of its c -oriented crystallinity. In contrast, SBT thin films produced at 750 °C with deposition rates of 0.37 nm/pulse demonstrated enhanced ferroelectric and piezoelectric responses due to mixed a -oriented crystallinity. In particular, the SBT thin film, fabricated at 750 °C with a lower deposition rate of 0.04 nm/pulse, demonstrated the most enhanced ferroelectric and piezoelectric properties due to its highly refined a -oriented crystallinity. Our findings illuminate the relationship between the characteristics of the crystals and functional properties in SBT thin films, highlighting the integration of a -domains within c -domains as a key strategy for optimizing SBT film performance and opening avenues for designing specialized Bi-layered perovskite thin films. [Display omitted] • Fabricated SBT thin films via PLD on Nb:STO substrates with varied conditions. • Crystal structure and surface morphology crucially affect ferroelectric and piezoelectric properties. • Optimal SBT film performance achieved through integration of a -domains within c -domains. [ABSTRACT FROM AUTHOR]

The asymmetric unit of the title compound, C14H13NO4, contains three independent mol­ecules, which differ slightly in conformation. Each contains an intra­molecular N--H...O hydrogen bond. In the crystal, O--H...O hydrogen bonds form chains of mol­ecules, which are linked into corrugated sheets parallel to (\overline{1}03) plane by C--H...O hydrogen bonds together with π inter­actions between the carbonyl groups and the 2-hy­droxy­phenyl rings. The layers are linked by further C--H...O hydrogen bonds. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions for the crystal packing are from H...H (49.0%), H...O/O...H (28.3%) and H...C/C...H (10.9%) inter­actions. van der Waals inter­actions are the dominant inter­actions in the crystal packing. Moreover, density functional theory (DFT) optimized structures at the B3LYP/6-311 G(d,p) level are compared with the experimentally determined mol­ecular structure in the solid state. The HOMO-LUMO behavior was elucidated to determine the energy gap of 4.53 eV. [ABSTRACT FROM AUTHOR]

The stability and mechanical properties of hydroxyapatite (HAp)/Chitosan composite materials depend on the dispersion of HAp aggregates in the chitosan matrix and on the chemical interaction between them. Therefore, hexagonal cross-sectioned HAp nanofibers were produced using a microwave-assisted hydrothermal method. Glutamic acid was used to control the HAp crystal growth; thereby, nanofibers were obtained with a preferential crystalline orientation, and they were grown along the "c" axis of HAp crystal structures. This morphology exposed the (300) and (100) crystal planes on the surface, and several phosphate groups and calcium ions were also exposed; they were able to form numerous chemical interactions with the amine, hydroxyl, and carbonyl groups of chitosan. Consequently, the final mechanical resistance of the composite materials was synergistically increased. Nanofibers were mixed with commercial chitosan using a sonotrode to improve their dispersion within the biopolymer matrix and prevent migration. The HAp nanofiber/Chitosan composite materials showed higher mechanical resistance than that observed in similar materials with the same chemical composition that were made of commercial HAp powders, which were used as reference materials. The mechanical resistance under tension of the composite materials made of nanofibers was similar to that reported for cortical bone. [ABSTRACT FROM AUTHOR]

Physical properties of objects depend on topological features of the corresponding triply periodic surfaces; thus topological exploration and classification of the surfaces has practical relevance. A general method is developed for generating triply periodic surfaces from triply periodic crystal structures. A triply periodic surface is derived from the natural tiling of a crystal network by an appropriate removal of some tile faces and subsequent smoothing of the resulting facet surface. The labyrinth nets of a generated triply periodic surface are built from the natural tiling, and in turn the topological parameters of the labyrinth nets are used to determine if the surface is isomorphic to a minimal surface. This method has been applied to all known 253 zeolite frameworks and 98 triply periodic surfaces were obtained, which belong to 55 topological types. Twelve surfaces were found to be isomorphic to already known triply periodic minimal surfaces (TPMSs), while four surfaces can be treated as isomorphic to new TPMSs. A procedure has also been developed for transferring the generated surfaces to a 3D‐printer‐readable format. [ABSTRACT FROM AUTHOR]

A Schiff base E-4-{[(5-bromothiophen-2-yl)methylidene]amino}-1,5-dimethyl-2-phenyl-1,2-dihydro-3H-pyrazol-3-one (4ATP) has been synthesized by condensation 5-bromothiophene-2-carboxaldehyde with 4-amino antipyrine by condensation. The compound crystallized in the monoclinic system (P21/n) with E-configuration at azomethine C = N bond. The Hirshfeld surface analysis and crystal structure data confirm the intramolecular hydrogen bonding interaction (C-H...O: 2.963 Å) in a conjugated six-membered cyclic structure. The IR, Raman, 1H NMR, 13C NMR and mass spectral studies have been interpreted based on the crystal structure data. The compound is more effective in its cytotoxic activity for the A549 cell line than that of Vero cells. [ABSTRACT FROM AUTHOR]

Objective. Intraoral polishing systems have become an alternative method for reglazing, which is important to prevent or minimize rapid wear of the opposing teeth. To assess the influence of different polishing systems and duration on surface roughness and crystal structure of zirconia was compared, contributing to the preparation and effect improvement of clinical zirconia restorations. Methods. Forty-eight zirconia specimens with equal size were fabricated by cutting and sintering zirconia discs. Then X-ray diffractometer (XRD) was adopted for examination of the specimens. Six specimens were selected as the grinding-polishing group (GL) after polishing, grinding, and glazing. Then six specimens were randomly selected from the remaining specimens as the grinding-unpolished group (GR) after surface conditioning by dental diamond burs. Subsequently, based on different polishing systems and duration, the rest of specimens were divided into following groups (n = 6): Youdent-20s group (Y20), Youdent-40s group (Y40), Youdent-60s group (Y60), Toboom-20s group (T20), Toboom-40s group (T40), and Toboom-60s group (T60). Additionally, a contour graph was applied for assessing the surface roughness of zirconia, scanning electron microscope (SEM) for observing surface topography, and X-ray diffraction analysis (XRD) for determining crystal structure of zirconia. Results. The GR group had the highest roughness, and the roughness of the specimens polished for 20 s with different polishing systems was significantly higher than those polished for 40 s and 60 s with the same polishing systems. There were no significant difference between the Y20 and T20 groups, while the roughness of the specimens in both Y40 and Y60 groups was significantly higher than that of the T40 and T60 groups. And with the increasing polishing duration, the surface morphology of the specimen was gradually smooth and the morphology was gradually regular. Besides, the surface scratches of the T group were shallower than that of the Y group at the same polishing duration. The peak value of XRD profile of the specimen after grinding and polishing process was consistent with the baseline pattern of that the original specimen. Conclusion. Glazing can reduce the surface roughness of the specimens. Besides, the polishing effect of Toboom (TOB) system (polishing duration = 60 s) is the best. And different polishing durations of TOB system have no significant effect on the crystal surface structure of the specimen. [ABSTRACT FROM AUTHOR]

Dendrite formation occurs on Li, Na, and Mg metal anodes in rechargeable batteries, and is a safety challenge, as well as a limiting factor for increasing energy- and power density. However, the behaviour of the dendrites differs depending on the anode material. In this study, we investigate the local bulk and surface crystal structure of Li, Na, and Mg surfaces to shed light on how differences in the morphology and structure of the anode surface and its metal deposits can explain differences in dendrite formation on Li, Na, and Mg anodes. The local bulk- and surface structure are found using molecular dynamics simulations in combination with the surface adaptive common neighbour analysis, and indicate that Li and Na surfaces are more prone to surface instabilities and formation of protrusions than Mg surfaces, which remain flat and hexagonal close-packed even near room temperature. Additionally, the equilibrium shapes of the Mg deposits obtained from density functional theory assume more flat and hexagonal shapes than the Li and Na deposits. Together, these results shed light on atomic mechanisms that may contribute to the different propensities of Li, Na, and Mg metal anodes to form dendrites. [ABSTRACT FROM AUTHOR]

Modulation of the structure, composition, and morphology through a simple refinement of the synthetic parameters is central to obtaining signature catalytic properties, enabling an understanding of the underlying growth and reaction mechanisms. In this study, a bismuth vanadate (BiVO4) model photocatalyst with several nanostructures (including pillar-like, dendrites, and microgranules) was fabricated by simple hydrothermal, solvothermal, and solid-state reaction (SSR) methods. As the solvothermal reaction temperature was increased, the tetragonal phase transformed into a monoclinic phase, and the inorganic nuclei interacted, self-assembled, and grew continuously to yield a well-defined architecture indicating the critical role of temperature in stabilizing the crystal structure and surface atomic features principally in an ethanol/water mixture. In contrast, conventional hydrothermal synthesis (only water as a solvent) resulted in single-phase BiVO4 pillars enriched with rough surfaces, sharp edges, and porous structures. The growth mechanism of the BiVO4 dendrites was investigated by the morphological evolutions from different reaction products obtained under different reaction conditions. BiVO4 has a bandgap energy in the visible spectral range (2.50–2.27 eV). Hence, BiVO4 architectures with exclusively controlled surfaces and crystal structures can be used as efficient photocatalysts to remove organic pollutants (methylene blue dye) in water. The solvothermally prepared BVO-SLR'24 with a mixed-phase (monoclinic and tetragonal zircon) structure exhibited superior photocatalytic activities for the decomposition of organic contaminants, which may be due to the unique connectivity between crystals, accelerated electron transfer, and heterojunction formation, compared to BiVO4 prepared with pure phase pillars and microgranules. This work highlights the significance of synthesis methodology and microstructural modification with the photophysical properties to reinvigorate the conventional design of visible-light-driven (VLD) photocatalysts. [ABSTRACT FROM AUTHOR]

Modulation of the structure, composition, and morphology through a simple refinement of the synthetic parameters is central to obtaining signature catalytic properties, enabling an understanding of the underlying growth and reaction mechanisms. In this study, a bismuth vanadate (BiVO4) model photocatalyst with several nanostructures (including pillar-like, dendrites, and microgranules) was fabricated by simple hydrothermal, solvothermal, and solid-state reaction (SSR) methods. As the solvothermal reaction temperature was increased, the tetragonal phase transformed into a monoclinic phase, and the inorganic nuclei interacted, self-assembled, and grew continuously to yield a well-defined architecture indicating the critical role of temperature in stabilizing the crystal structure and surface atomic features principally in an ethanol/water mixture. In contrast, conventional hydrothermal synthesis (only water as a solvent) resulted in single-phase BiVO4 pillars enriched with rough surfaces, sharp edges, and porous structures. The growth mechanism of the BiVO4 dendrites was investigated by the morphological evolutions from different reaction products obtained under different reaction conditions. BiVO4 has a bandgap energy in the visible spectral range (2.50–2.27 eV). Hence, BiVO4 architectures with exclusively controlled surfaces and crystal structures can be used as efficient photocatalysts to remove organic pollutants (methylene blue dye) in water. The solvothermally prepared BVO-SLR'24 with a mixed-phase (monoclinic and tetragonal zircon) structure exhibited superior photocatalytic activities for the decomposition of organic contaminants, which may be due to the unique connectivity between crystals, accelerated electron transfer, and heterojunction formation, compared to BiVO4 prepared with pure phase pillars and microgranules. This work highlights the significance of synthesis methodology and microstructural modification with the photophysical properties to reinvigorate the conventional design of visible-light-driven (VLD) photocatalysts. [ABSTRACT FROM AUTHOR]

In the title compound, C14H8Br2FN3O2, the nitro-substituted benzene ring and the 4-fluoro­phenyl ring form a dihedral angle of 65.73 (7)°. In the crystal, mol­ecules are linked into chains by C—HO hydrogen bonds running parallel to the c-axis direction. The crystal packing is consolidated by C—Fπ inter­actions and π–π stacking inter­actions, and short BrO [2.9828 (13) Å] contacts are observed. The Hirshfeld surface analysis of the crystal structure indicates that the most important contributions to the crystal packing are from HH (17.4%), OH/HO (16.3%), BrH/HBr (15.5%), BrC/CBr (10.1%) and FH/HF (8.1%) contacts. [ABSTRACT FROM AUTHOR]

We advance a theory for the nanoscale patterns that emerge spontaneously when the (001) surface of a crystal is bombarded with a broad ion beam and the crystal structure remains intact. Both normal incidence bombardment and oblique incidence bombardment with concurrent sample rotation are studied. For suitable parameter choices, our equation of motion produces patterns that are remarkably similar to recently-discovered transitional patterns on the (001) surface of germanium, to the patterns of inverted square pyramids that form on the (001) surface of silicon, and to the various patterns produced by oblique incidence bombardment of a rotating Ge (001) surface. A novel term that comes from curvature dependent sputtering is responsible for the isolated peaks present in the transitional patterns. [ABSTRACT FROM AUTHOR]

The spinel LiMn 2 O 4 cathode material shows severe capacity degradation due to Jahn–Teller distortion and dissolution of Mn during the charge-discharge process. Herein, a series of single crystal truncated octahedral of LiFe 0.03 B x Mn 1.97−x O 4 (0≤x≤0.10) were synthesized by simple solid-state combustion combined with Fe-B co-doping, morphology and particle size controlling strategy. Through Fe-B co-doping, not only the LiFe 0.03 Mn 1.97 O 4 containing {111}, {100} and {110} planes are successfully controlled to the particles containing only {111} and {100} planes, but also the near-nanometer particles are controlled to bigger submicron sizes. It is found that Fe-B co-doping can enhance the stability of the crystal structure, inhibit Jahn-Teller distortion and reduce the dissolution of Mn. Among them, the optimized LiFe 0.03 B 0.08 Mn 1.89 O 4 forms a truncated octahedral single crystal particle with good crystallization and only {111} and {100} crystal faces, and the particle size is around 349.3 nm, showing exceptional high rate capacity and long cycle life. The LiFe 0.03 B 0.08 Mn 1.89 O 4 releases a high initial discharge capacity of 107.1 mAh/g with a capacity retention of 77.7% after 1000 cycles at 10 C, which is higher than that of the LiFe 0.03 Mn 1.97 O 4 (58.8%). Even at 20 C, LiFe 0.03 B 0.08 Mn 1.89 O 4 still achieves a high reversible specific capacity (90.4 mAh/g) and outstanding long-cycle stability (81.3%, 1000th). This work provides a scientific basis for the crystal surface control and particle size control of spinel LiMn 2 O 4 , which is of great significance for the development of the next generation of high-power lithium-ion batteries. [Display omitted] • The spinel-type LiMn2O4 was modified by the strategy combining Fe-B co-doping, regulation of crystal surface and particle size. • Through Fe-B co-doping, not only the LiFe0.03Mn1.97O4 containing {111}, {100} and {110} planes are successfully controlled to the particles containing only {111} and {100} planes, but also the near-nanometer particles are controlled to bigger submicron sizes. • The optimized truncated octahedral LiFe0.03B0.08Mn1.89O4 exhibited excellent high rate performance and long cycle life. [ABSTRACT FROM AUTHOR]

This work carried out research of the adsorption processes of O2 molecules on ZnO nanoclusters under different initial conditions by molecular dynamics method. To describe the interaction between atoms, we used the reactive force field (ReaxFF) interatomic potential. Several computer experiments were conducted with different initial conditions. We have been found that the whole process of adsorption was divided into two stages, the first stage was characterized by a rapid increase in the number of adsorbed molecules, the second one an increase of fluctuations in the change of adsorbed molecules on the surface over time. The higher gas pressure in the system corresponds to the greater number of O2 molecules diffusing into the volume of the ZnO nanocluster, therefore, the crystal structure of the surface of the ZnO nanocluster becomes amorphous. In addition, it was established that the tendencies of distribution of the dependence of the central symmetry parameter with the oxygen concentration in the system (NO2 < 100 molecules) were similar. The situation was quite different when the number of oxygen molecules increased: the value of the central symmetry parameter of surface atoms was more evenly distributed, which cannot be considered as a crystalline state of ZnO nanocluster. [ABSTRACT FROM AUTHOR]

The polycrystalline sample (Ba0.05Bi0.95)(Fe0.95Zr0.05)O3 was prepared by solid state reaction method at 850 °C. The crystal structure and surface morphology of the sample were obtained by using X-ray diffractometer and a scanning electron microscope respectively. The frequency dependence of electrical parameters using impedance spectroscopy provides the dielectric behavior and grain and grain boundary effect toward resistance and capacitance of the sample. The conduction mechanism of the sample was studied from frequency dependent ac conductivity. The ferroelectricity of the sample was studied by p-E loop at room temperature. The slope from J–E characteristics was found to be nearly equal to 1. [ABSTRACT FROM AUTHOR]

The polycrystalline sample (Ba0.05Bi0.95)(Fe0.95Zr0.05)O3 was prepared by solid state reaction method at 850 °C. The crystal structure and surface morphology of the sample were obtained by using X-ray diffractometer and a scanning electron microscope respectively. The frequency dependence of electrical parameters using impedance spectroscopy provides the dielectric behavior and grain and grain boundary effect toward resistance and capacitance of the sample. The conduction mechanism of the sample was studied from frequency dependent ac conductivity. The ferroelectricity of the sample was studied by p-E loop at room temperature. The slope from J–E characteristics was found to be nearly equal to 1. [ABSTRACT FROM AUTHOR]

Let K be a convex polyhedron and ℱ its Wulff energy, and let CK denote the set of convex polyhedra close to K whose faces are parallel to those of K. We show that, for sufficiently small ε, all ε‐minimizers belong to CK. As a consequence of this result we obtain the following sharp stability inequality for crystalline norms: There exist γ = γ(K, n) > 0 and σ = σ(K, n) > 0 such that, whenever ∣E ∣ = ∣ K∣ and ∣EΔK ∣ ≤ σ, thenℱE−ℱKa≥γ∣EΔKa∣forsomeKa∈CK. In other words, the Wulff energy ℱ grows very fast (with power 1) away from CK. The set Ka∈CK appearing in the formula above can be informally thought as a sort of "projection" of E onto CK. Another corollary of our result is a very strong rigidity result for crystals: For crystalline surface tensions, minimizers of ℱ(E) + ∫Eg with small mass are polyhedra with sides parallel to the those of K. In other words, for small mass, the potential energy cannot destroy the crystalline structure of minimizers. This extends to arbitrary dimensions a two‐dimensional result obtained in [9]. © 2020 Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

Quartz crystal microbalance (QCM) is one of the powerful tools for the studies of molecular recognition and chiral discrimination. Its efficiency mainly relies on the design of the functional sensitive layer on the electrode surface. However, the organic sensitive layer may easily cause dissipation of oscillation or detachment and weaken the signal transfer during the molecular recognition processes. In this work, we reveal for the first time that the bare metal surface without the organic selector layer has the capability for chiral recognition in the QCM system. During the adsorption of various chiral amino acids, relatively higher selectivity of D‐enantiomers on gold (Au) surface was shown by the QCM detection. Based on analyses of the surface crystalline structure and density functional theory calculations, we demonstrate that the chiral nature of Au surface plays an important role in the selective binding of specific D‐amino acids. These results may open new insights on chiral detection by QCM system. It will also promote the construction of novel chiral sensing systems with both efficient detection and separation capability. [ABSTRACT FROM AUTHOR]