Local Structures and Chemical Properties of Deprotonated Arginine

气体的 deprotonated 精氨酸的势能表面被第一原则计算系统地调查了。在 B3LYP/6-31G (d) 水平，除了几稳定的本地结构的鉴定，新全球最小被定位它是比什么更稳定的大约 6.56 kJ/mol 被报导了。deprotonated 精氨酸分子在羧化物组与 deprotonation 有二种不同形式(咕咕叫) 。这二种形式被一个很高的精力障碍衔接并且拥有很不同的红外光谱侧面。我们的计算质子分离精力和精氨酸分子的煤气阶段的酸味被发现在对相应试验性的结果的好同意。预言的几何学，偶极子时刻，旋转常数，垂直电离精力和低精力 conformers 的红外系列将为未来是有用的试验性的大小。

A novel water layer structure inside nanobubbles at room temperature

Molecularly thin water layer, with a hydrogen bonding network different from those in bulk water and ice, has unique properties and is generally involved in many important processes such as wetting, erosion, atmosphere chemical reaction, protein folding and biomolecular interaction. Here, we report a new water layer structure at room temperature, which is found inside nanobubbles by using synchrotron based scanning transmission soft X-ray microscopy(STXM). The three peaks 535.0, 536.8 and 540.9 e V at O K edge inside the nanobubbles show a novel characteristics of very thin water layers, which has never been observed before.

Density Functional Theory Study on Raman Spectra of Rhodamine Molecules in Different Forms

玫瑰精分子是为与拉曼光谱学有关的应用的最使用的染料之一。我们系统地学习了玫瑰精 6G 的拉曼系列，玫瑰精 123，并且玫瑰精 B (RhB ) 分子使用密度功能的理论。它与 BP86 被发现那功能 cationic 玫瑰精分子的计算拉曼系列在对在水的答案的相应试验性的系列的好同意。相反的离子，氯，和特定的氢契约的参与在能部分在答案并且在金表面上解释 RhB 的拉曼系列之间的观察差别的 RhB 的拉曼系列上有显著效果，这被显示出。它也显示对表面的精确描述提高了仍然在金属表面上为玫瑰精分子散布的拉曼要求考虑界面的相互作用导致的变化。

Core-Excited Molecules by Resonant Intense X-Ray Pulses Involving Electron-Rotation Coupling

It has been reported that electron-rotation coupling plays a significant role in diatomic nuclear dynamics induced by intense VUV pulses [Phys. Rev. A 102(2020) 033114;Phys. Rev. Res. 2(2020) 043348]. As a further step, we present here investigations of the electron-rotation coupling effect in the presence of Auger decay channel for core-excited molecules, based on theoretical modeling of the total electron yield(TEY), resonant Auger scattering(RAS) and x-ray absorption spectra(XAS) for two showcases of CO and CH^(+) molecules excited by resonant intense x-ray pulses. The Wigner D-functions and the universal transition dipole operators are introduced to include the electron-rotation coupling for the core-excitation process. It is shown that with the pulse intensity up to 10^(16) W/cm^(2), no sufficient influence of the electron-rotation coupling on the TEY and RAS spectra can be observed. This can be explained by a suppression of the induced electron-rotation dynamics due to the fast Auger decay channel, which does not allow for effective Rabi cycling even at extreme field intensities,contrary to transitions in optical or VUV range. For the case of XAS, however, relative errors of about 10% and 30% are observed for the case of CO and CH^(+), respectively, when the electron-rotation coupling is neglected.It is concluded that conventional treatment of the photoexcitation, neglecting the electron-rotation coupling,can be safely and efficiently employed to study dynamics at the x-ray transitions by means of electron emission spectroscopy, yet the approximation breaks down for nonlinear processes as stimulated emission, especially for systems with light atoms.

More Stable, More Estrogenic: The SERM-ERα LBD Complex

Many synthetic selective estrogen receptor modulators (SERMs) have been cocrystallized with the human estrogen receptor α ligand binding domain (ERα LBD). Despite stabilizing the same canonical inactive conformation of the LBD, most SERMs display different ligand-dependent pharmacological profiles. We show here that increased partial agonism of SERMs is associated with increased conformational stability of the SERM-LBD complexes, by investigation of dihydrobenzoxathiin-based SERMs using molecular modelling techniques. Analyses of tamoxifen (TAM) and 4-hydroxytamoxifen (OHT) in complex with the LBD furthermore indicates that the conversion of TAM to OHT increases both the affinity to ERα and the partial agonism of the anti-cancer drug, which provides a plausible explanation of the counterintuitive results of TAM therapy.

by a cascade optical field modulation strategy facilitating selective multispectral narrow-band near-infrared photodetection

Since selective detection of multiple narrow spectral bands in the near-infrared(NIR)region still poses a fundamental challenge,we have,in this work,developed NIR photodetectors(PDs)using photon upconversion nanocrystals(UCNCs)combined with perovskite films.To conquer the relatively high pumping threshold of UCNCs,we designed a novel cascade optical field modulation strategy to boost upconversion luminescence(UCL)by cascading the superlensing effect of dielectric microlens arrays and the plasmonic effect of gold nanorods,which readily leads to a UCL enhancement by more than four orders of magnitude under weak light irradiation.By accommodating multiple optically active lanthanide ions in a core-shell-shell hierarchical architecture,developed PDs on top of this structure can detect three well-separated narrow bands in the NIR region,i.e.,those centered at 808,980,and 1540 nm.Due to the large UCL enhancement,the obtained PDs demonstrate extremely high responsivities of 30.73,23.15,and 12.20 AW^(−1) and detectivities of 5.36,3.45,and 1.91×10^(11) Jones for 808,980,and 1540 nm light detection,respectively,together with short response times in the range of 80-120 ms.Moreover,we demonstrate for the first time that the response to the excitation modulation frequency of a PD can be employed to discriminate the incident light wavelength.We believe that our work provides novel insight for developing NIR PDs and that it can spur the development of other applications using upconversion nanotechnology.

New progress in theoretical studies on palladium-catalyzed C-C bond-forming reaction mechanisms

This review reports a series of mechanistic studies on Pd-catalyzed C-C cross-coupling reactions via density functional theory(DFT) calculations.A brief introduction of fundamental steps involved in these reactions is given,including oxidative addition,transmetallation and reductive elimination.We aim to provide an important review of recent progress on theoretical studies of palladium-catalyzed carbon-carbon cross-coupling reactions,including the C-C bond formation via C-H bond activation,decarboxylation,Pd(Ⅱ)/Pd(Ⅳ) catalytic cycle and double palladiums catalysis.

Modulation of photovoltaic behavior of dye-sensitized solar cells by electron donors of porphyrin dyes and cosensitization

Porphyrin dyes have received great attention due to their excellent photovoltaic performance in dye- sensitized solar cells （DSSCs）. In this work, dyes XCI-XC3 were synthesized by introducing various numbers of bis（4-methoxyphenyl）amino and p-hexyloxyphenyl groups to porphyrin meso-positions. The XC1 molecule contains two p-hexyloxyphenyl groups, and its DSSCs showed the power conversion efficiency of 4.81%. For XC2 and XC3, the replacement of p-hexyloxyphenyl with diphenylamino groups can effectively enhance the light harvesting around 500 nm. However, the highest occupied molecular orbitals （HOMOs） were elevated too much, which suppressed the dye regeneration processes, leading to low cell efficiencies of 2.51% and 1.27% for XC2, and XC3, respectively. To further improve the cell performance, an anthracene derivative Cl was used as the cosensitizer for XCl, which increased both the Jsc and Voc values, with an improved efficiency of 5.75：g.

Isolation and Identification of Pseudo Seven-Coordinate Ru(Ⅲ)Intermediate Completing the Catalytic Cycle of Ru-bda Type of Water Oxidation Catalysts

Isolation of RuⅢ-bda(17-electron specie)complex with an aqua ligand(2-electron donor)is challenging due to violation of the 18-electron rule.Although considerable efforts have been dedicated to mechanistic studies of water oxidation by the Ru-bda family,the structure and initial formation of the Ru^(Ⅲ)-bda aqua complex are still controversial.Herein,we challenge this often overlooked step by designing a pocketshape Ru-based complex 1.The computational studies showed that 1 possesses the crucial hydrophobicity at the Ru^(V)(O)state as well as similar probability of access of terminal O to solvent water molecules when compared with classic Ru-bda catalysts.Through characterization of single-crystal structures at the Ru^(Ⅱ) and Ru^(Ⅲ) states,a pseudo seven-coordinate“ready-togo”aqua ligand with Ru^(Ⅲ)…O distance of 3.62A was observed.This aqua ligand was also found to be part of a formed hydrogen-bonding network,providing a good indication of how the Ru^(Ⅲ)-OH_(2)complex is formed.

Dynamics and self-assembly of bio-functionalized gold nanoparticles in solution： Reactive molecular dynamics simulations

The self-assembling properties, stability, and dynamics of hybrid nanocarriers （gold nanoparticles （AuNPs） functionalized with cysteine-based peptides） in solution are studied through a series of classical molecular dynamics simulations based on a recently parametrized reactive force field. The results reveal, at the atomic level, all the details regarding the peptide adsorption mechanisms, nanoparticle stabilization, aggregation, and sintering. The data confirm and explain the experimental findings and disclose aspects that cannot be scrutinized by experiments. The biomolecules are both chemisorbed and physisorbed; self-interactions of the adsorbates and formation of stable networks of inter- connected molecules on the AuNP surfaces limit substrate reconstructions, protect the AuNPs from the action of the solvent, and prevent direct interactions of the gold surfaces. The possibility of agglomeration of the functionalized nanoparticles, compared with the sintering of the bare supports in a water solution, is demonstrated through relatively long simulations and fast steered dynamics. The analysis of the trajectories reveals that the AuNPs were well stabilized by the peptides. This prevented particle sintering and kept the particles far apart; however, part of their chains could form interconnections （crosslinks） between neighboring gold vehicles. The excellent agreement of these results with the literature confirm the reliability of the method and its potential application to the modeling of more complex materials relevant to the biomedical sector.

软X射线光谱的第一性原理模拟(英文)

软X射线光谱是通过核激发或去激发以探测分子、表面及各种化合物的电子结构和化学结构的有效的测量技术。本文对基于密度泛函理论描述X射线吸收、发射的各种不同过程的计算方法进行了综述。重点讨论了各种方法的基本原理、实际操作和具体应用。提供了K边X射线光电子能谱、吸收和发射光谱详细的模拟细节以及一些代表性体系的算例(包括分子、富勒烯、碳纳米管、单层石墨和DNA链)。

Conductivity of carbon-based molecular junctions from ab-initio methods

碳 nanomaterials (CNM ) 为下次辈份的电子学正在推动候选人。在这评论，我们在从 ab-initio 方法获得的基于碳的分子的连接的传导性上提供最近的结果的微型概述。当在分子的连接的 nanoelectrodes 和分子的材料被讨论， CNM 使用了。包括使用 CNM 认识到的 nanomechanically 控制的分子的传导力开关，否定微分抵抗设备，和电子整流器的功能被表明了。

Novel Organic Dyes Based on Bulky Tri（triphenylamine）-Substituted Styrene for Dye-Sensitized Solar Cells

Three novel donor-n-acceptor （D-π-A） metal-free organic dyes （TB, TS and TF） based on tri（triphenylamine）- substituted styrene as donor with various conjugated linkers （benzene, thiophene and furan） were synthesized, characterized and used for the application of dye-sensitized solar cells （DSSCs）. Under the same condition, The photo-to-electrical conversion efficiency of the DSSCs sensitized with TB, TS and TF reach 1.84%, 4.10% and 4.52%, respectively, which are lower than that sensitized with RI （5.02%） with one triphenylamine unit. The results suggest that these bulky donor-based sensitizers are unfavorable to DSSCs.

Visualizing Material Processing via Photoexcitation-ControlledOrganic-Phase Aggregation-Induced Emission

Aggregation-induced emission(AIE)has been much employed for visualizing material aggregation and self-assembly.However,water is generally required for the preparation of the AIE aggregates,the operation of which limits numerous material processing behaviors.Employing hexathiobenzene-based small molecules,monopolymers,and block copolymers as different material prototypes,we herein achieve AIE in pure organic phases by applying a nonequilibrium strategy,photoexcitationcontrolled aggregation.This strategy enabled a dynamic change of molecular conformation rather than chemical structure upon irradiation,leading to a continuous aggregation-dependent luminescent enhancement(up to~200-fold increase of the luminescent quantum yield)in organic solvents.Accompanied by the materialization of the nonequilibrium strategy,photoconvertible self-assemblies with a steady-state characteristic can be achieved upon organic solvent processing.The visual monitoring with the luminescence change covered the whole solution-to-film transition,as well as the in situ photoprocessing of the solid-state materials.

Switching the O-O Bond Formation Pathways of Ru-pda Water Oxidation Catalyst by Third Coordination Sphere Engineering

Water oxidation is a vital anodic reaction for renewable fuel generation via electrochemical-and photoelectrochemical-driven water splitting or CO_(2)reduction.Ruthenium complexes,such as Ru-bda family,have been shown as highly efficient wateroxidation catalysts(WOCs),particularly when they undergo a bimolecular O-O bond formation pathway.In this study,a novel Ru(pda)-type(pda^(2–)=1,10-phenanthroline-2,9-dicarboxylate)molecular WOC with 4-vinylpyridine axial ligands was immobilized on the glassy carbon electrode surface by electrochemical polymerization.Electrochemical kinetic studies revealed that this homocoupling polymer catalyzes water oxidation through a bimolecular radical coupling pathway,where interaction between two Ru(pda)–oxyl moieties(I2M)forms the O-O bond.The calculated barrier of the I2M pathway by densityfunctional theory(DFT)is significantly lower than the barrier of a water nucleophilic attack(WNA)pathway.By using this polymerization strategy,the Ru centers are brought closer in the distance,and the O-O bond formation pathway by the Ru(pda)catalyst is switched from WNA in a homogeneous molecular catalytic system to I2M in the polymerized film,providing some deep insights into the importance of third coordination sphere engineering of the water oxidation catalyst.

Effect of dihedral angle of bridge unit on the performance of dye-sensitized solar cell

In this work, we investigated the impact of bridge unit on their photo-physical and photovoltaic performance. Increased planarity of the dyes effectively extended the absorption, but reduces the efficiency. Interestingly we found that dyes with a thiophene conjugate unit showed inferior performance when compared with benzene. Theoretical computation indicates a large dihedral angle in the latter system. EIS analysis evidenced the severe recombination in the thiophene-based dye,showing that good planarity may lead to dye aggregation and decrease the efficiency.