Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instr...Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instrument function,is measured in X-ray Thom-son scattering(XRTS)experiments,which allow the study of electronic structure properties at the microscopic level.Among the various ab initio methods,linear-response time-dependent density-functional theory(LR-TDDFT)is a key framework for simulating the DSF.The standard approach in LR-TDDFT for computing the DSF relies on the orbital representation.A significant drawback of this method is the unfavorable scaling of the number of required empty bands as the wavenumber increases,making LR-TDDFT impractical for modeling XRTS measurements over large energy scales,such as in backward scattering geometry.In this work,we consider and test an alternative approach to LR-TDDFT that employs the Liouville–Lanczos(LL)method for simulating the DSF of WDM.This approach does not require empty states and allows the DSF at large momentum transfer values and over a broad frequency range to be accessed.We compare the results obtained from the LL method with those from the solution of Dyson’s equation using the standard LR-TDDFT within the projector augmented-wave formalism for isochorically heated aluminum and warm dense hydrogen.Additionally,we utilize exact path integral Monte Carlo results for the imaginary-time density-density correlation function(ITCF)of warm dense hydrogen to rigorously benchmark the LL approach.We discuss the application of the LL method for calculating DSFs and ITCFs at different wavenumbers,the effects of pseudopotentials,and the role of Lorentzian smearing.The successful validation of the LL method under WDM conditions makes it a valuable addition to the ab initio simulation landscape,supporting experimental efforts and advancing WDM theory.展开更多
Based on spin-unrestricted hartree fock theory, we present the spin unrestricted multi- configuration time dependent hartree lock theory （UMCTDHF） to describe the electron correlation dynamics of systems interacting...Based on spin-unrestricted hartree fock theory, we present the spin unrestricted multi- configuration time dependent hartree lock theory （UMCTDHF） to describe the electron correlation dynamics of systems interacting with laser field. The positive spin orbitals and the negative spin orbitals are propagated in their own subspace respectively. The spin orbital in the spin-down subspace acts with that in the spin-up subspace by the reduced density matrix and mean field operator. The ground energy is acquired by propagating the trial wave function in the imaginary time by using spin-restricted MCTDHF （RMCTDHF） and UMCTDHF respectively. Then the ionization probabilities and the electrons energies are calculated by using RMCTDHF and UMCTDHF when the laser field is present. The ionization probability calculated with UMCTDHF agrees with the previous theoretical reports very well. The UMCTDHF method is accurate and applicable for open shell system beyond the capability of the RMCTDHF method.展开更多
A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescenc...A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.展开更多
Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of tem...Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of temperature, and the critical cooling rates required for the formation of amorphous α Al at different neodymium concentrations were calculated too. The addition of neodymium increases the amorphizablity of α Al by increasing the incubation time and decreasing the nucleation rate and the critical cooling rate. The calculations are fitted to experimental results when liquidus temperatures are estimated from an approximation, which treats Al Fe V Si Nd as quasi binary Al Fe system.展开更多
Radio is all about dreams. This old and tired medium now fights with new media as it is with its old enemy television. Radio has a big impact on dreams. It gives you the sound and makes you dream. Once you get used to...Radio is all about dreams. This old and tired medium now fights with new media as it is with its old enemy television. Radio has a big impact on dreams. It gives you the sound and makes you dream. Once you get used to this media you start dreaming. If you used to listen radio more, you get in dependence with it. So this day dreaming change to lifeless dreaming. This article gives an evaluation of how radio audience can shape audience future dreams with dependence theory. The paper starts with a conceptual explanation of dependence theory and goes on with a survey done in Turkey to 101 radio listeners. The survey investigates on how people like listening the radio and what makes them enjoy radio. The survey assumes that people listening to radio and getting depended on it start changing the behaviors and habits of listeners. This behavior change effects listeners future dreams and the audience take radio as a model. The paper shows by using the dependence theory that radio listeners take the radio they love as model and use it to build their future business dreams.展开更多
As the Sarawak state government accelerates infrastructure development to stimulate economic growth,it has attracted numerous foreign construction enterprises-particularly Chinese firms-entering the market through low...As the Sarawak state government accelerates infrastructure development to stimulate economic growth,it has attracted numerous foreign construction enterprises-particularly Chinese firms-entering the market through low-cost bidding.However,this foreign-dominated model,while improving efficiency,has triggered local enterprise marginalization,industrial chain fragmentation,payment delays,and project setbacks,undermining the intended economic spillover effects of public investment.Grounded in policy analysis and field evidence within a dependency theory framework,this study evaluates the structural impacts of foreign participation on Sarawak’s local economy,uncovers governance gaps,and proposes strategies to enhance local economic resilience under open-market conditions.The findings reveal that foreign contractors(especially Chinese enterprises),despite their capital and technological advantages in dominating mega-projects,exhibit pervasive shortcomings:inadequate local participation(falling far below the 40%policy target),deficient knowledge transfer(local firms hold only 6%of green technology patents),significant value leakage(foreign profit repatriation dominated project value flows),and widespread execution delays/cost overruns due to underestimation of tropical climate-geological risks,institutional maladaptation,and resource misallocation.Drawing on experiences from the Philippines,Indonesia,and Vietnam,the study proposes systemic reforms:introducing a Low-Bid Risk Evaluation System(LRES),enforcing a mandatory Local Participation Index(LPI),establishing a Smart-Contract-Based Digital Payment Chain System(DPCS)to protect subcontractors,and requiring pre-bid local adaptation training for foreign contractors.These recommendations aim to construct“embedded institutional resilience,”transforming policy intent into executable governance mechanisms to ensure infrastructure investment genuinely serves Sarawak’s inclusive and sustainable growth.展开更多
Permanent dipole moments induced high-order harmonic generation(HHG)signals offer a potential approach to producing elliptically or even circularly polarized X-ray attosecond sources.Previous studies on this topic hav...Permanent dipole moments induced high-order harmonic generation(HHG)signals offer a potential approach to producing elliptically or even circularly polarized X-ray attosecond sources.Previous studies on this topic have mainly focused on diatomic molecules such as CO and HeH.Based on this scheme,significant HHG signals in the direction perpendicular to the molecular axis can be observed in both the high-energy and low-energy regions.However,we found that the high-order harmonics induced by the permanent dipole moments of polyatomic complex molecules involve more intricate physical processes.Using time-dependent density functional theory,we simulated the dynamics of HHG from NH2COOH and NH2COSH interacting with linearly polarized lasers.We found that the harmonic signals in the direction perpendicular to the N-C bond were significantly enhanced in the high-energy photon region.Our analysis indicates that this is due to the complex molecular configuration of NH_(2)COOH and NH_(2)COSH:while the NH_(2) group has C_(2v) symmetry,both COOH and COSH groups lack this symmetry.This structural characteristic results in permanent dipole moments being felt only when electrons return to either COSH or COOH groups,but not to NH_(2) group.Additionally,our results reveal a multi-plateau structure in HHG signal along laser polarization direction,a phenomenon arising from multi-electron and multiorbital effects during interaction between complex molecule and strong laser field.展开更多
Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechan...Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechanics states that Schrödinger’s equation (a deterministic law) governs spontaneous processes while measurement processes are ruled by probability laws. It is well established that time dependent perturbation theory must be used for solving problems involving time. In order to account for spontaneous processes, this last theory makes use of laws valid only when measurements are performed. This incoherence seems absent from the literature.展开更多
The study of various oxidation states of chromium with Sargassum <i>sp</i>. is of particular interest since hexavalent chromium </span><span style="font-size:10.0pt;font-family:""&g...The study of various oxidation states of chromium with Sargassum <i>sp</i>. is of particular interest since hexavalent chromium </span><span style="font-size:10.0pt;font-family:"">is </span><span style="font-size:10.0pt;font-family:"">reduced to trivalent chromium in </span><span style="font-size:10.0pt;font-family:"">an </span><span style="font-size:10.0pt;font-family:"">aqueous solution. In this study, a systematic density functional theory (DFT) calculations were performed to study the interactions of transition metal chromium ion with different oxidation states and spin states with the <i>Sar</i></span><i><span style="font-size:10.0pt;font-family:"">gassum sp</span></i><span style="font-size:10.0pt;font-family:"">. decorated with carboxylate</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">(acetate) at the wB97XD/6-311++</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">G(d,p)</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">level of theory. The structures and binding energies of chromium met<span>al</span></span><span style="font-size:10.0pt;font-family:"">-</span><span style="font-size:10.0pt;font-family:"">carboxylate complexes at various oxidation states and spin states in gas</span><span style="font-size:10.0pt;font-family:""> phase were examined. The coordination strength of Cr(VI) with the acetate <span>ligand was predominantly the strongest compare</span></span><span style="font-size:10.0pt;font-family:"">d</span><span style="font-size:10.0pt;font-family:""> to the other oxidation</span><span style="font-size:10.0pt;font-family:""> states. <span>Vibrational frequency analysis, for the homoleptic monomers of tris</span> <span>[</span><span>Cr<sup>III</sup>(AC)<sub>3</sub>]<sup>0</sup> and </span>[Cr<sup>VI</sup>(AC)<sub>3</sub>]<sup>3+</sup> complexes, illustrate good harmony with the experimental and<span> theoretical calculated frequencies. Using the time</span></span><span style="font-size:10.0pt;font-family:"">-</span><span style="font-size:10.0pt;font-family:"">dependent DFT</span><span style="font-size:10.0pt;font-family:""> (TD-DFT) at the level of CAM-B3LYP/6-311++G(d,p), the vertical excitation energies were obtained. The stabilization energies derived using the second order perturbation </span><span style="font-size:10.0pt;font-family:"">theory, <i>E</i><sub>ij</sub><sup>(2)</sup>, of NBO analysis confirmed the greater charge transfer for the</span><span style="font-size:10.0pt;font-family:""> observed trends in the metal binding. The calculated binding </span><span style="font-size:10.0pt;font-family:"">energies</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">(ΔE) and interactions energies </span><span style="font-size:10.0pt;font-family:Symbol;">S</span><i><span style="font-size:10.0pt;font-family:"">E</span></i><sub><span style="font-size:10.0pt;font-family:"">ij</span></sub><sup><span style="font-size:10.0pt;font-family:"">(2)</span></sup><span style="font-size:10.0pt;font-family:""> favor</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">the formation of</span><span style="font-size:10.0pt;font-family:""> [Cr<sup>VI</sup>(AC)<sub>3</sub>]<sup>3+</sup> complexes. The findings of this study identify efficient electronic factors as major contributors to the metal binding affinities, with promising possibilities for the design of metal-ligand complexes and sensing of the metal ions.展开更多
Community-based social organizations play a vital role in grassroots governance but generally face resource dependence dilemmas that constrain their capacity building and sustainable development.Based on Resource Depe...Community-based social organizations play a vital role in grassroots governance but generally face resource dependence dilemmas that constrain their capacity building and sustainable development.Based on Resource Dependence Theory(RDT),this study addresses the limitations of existing research,such as the lack of an integrated framework and insufficient exploration of bidirectional interaction mechanisms,by systematically analyzing the current state of resource dependence among community-based social organizations.The study constructs a three-dimensional capacity-building strategy:optimizing dependency structures through the establishment of a diversified resource supply network;enhancing resource acquisition capabilities through identification,integration,and utilization of resources;and cultivating organizational autonomy through governance structures,professional competencies,and organizational culture.These strategies provide both theoretical support and practical pathways for community-based social organizations to overcome resource constraints and achieve sustainable development.展开更多
First-principles electron dynamics calculations can be applied in the investigation of a wide range of ultrafast phenomena in attosecond physics.They offer unique microscopic insight into light-induced ultrafast pheno...First-principles electron dynamics calculations can be applied in the investigation of a wide range of ultrafast phenomena in attosecond physics.They offer unique microscopic insight into light-induced ultrafast phenomena in both gas and condensed phases of matter,and thus,they are apowerful tool to develop our understanding of the physics of attosecond phenomena.We specifically review techniques employing time-dependent density functional theory(TDDFT)for investigating attosecond and strong-field phenomena.First,we describe this theoretical framework that enables the modeling of perturbative and non-perturbative electron dynamics in materials,including atoms,molecules,and solids.We then discuss its application to attosecond experiments,focusing on the reconstruction of attosecond beating by interference of two-photon transitions(RABBIT)measurements.Wealso briefly review first-principles calculations of optical properties of solids with TDDFT in the linear response regime and their extension to calculations of transient optical properties of solids in non-equilibrium phases,by simulating experimental pump-probe setups.We further demonstrate the application of TDDFT simulation to high-order harmonic generation in solids.First-principles calculations have predictive power,and hence they can be utilized to design future experiments to explore nonequilibrium and nonlinear ultrafast phenomena in matter and characterize and control metastable light-induced quantum states.展开更多
Spin excitations play a fundamental role in understanding magnetic properties of materials,and have significant technological implications for magnonic devices.However,accurately modeling these in transition-metal and...Spin excitations play a fundamental role in understanding magnetic properties of materials,and have significant technological implications for magnonic devices.However,accurately modeling these in transition-metal and rare-earth compounds remains a formidable challenge.Here,we present a fully first-principles approach for calculating spin-wave spectra based on time-dependent(TD)density-functional perturbation theory(DFPT),using nonempirical Hubbard functionals.This approach is implemented in a general noncollinear formulation,enabling the study of magnons in both collinear and noncollinear magnetic systems.Unlike methods that rely on empirical Hubbard U parameters to describe the ground state,and Heisenberg Hamiltonians for describing magnetic excitations,the methodology developed here probes directly the dynamical spin susceptibility(efficiently evaluated with TDDFPT throught the Liouville-Lanczos approach),and treats the linear variation of the Hubbard augmentation(in itself calculated non-empirically)in full at a self-consistent level.Furthermore,the method satisfies the Goldstone condition without requiring empirical rescaling of the exchange-correlation kernel or explicit enforcement of sum rules,in contrast to existing state-of-the-art techniques.We benchmark the novel computational scheme on prototypical transition-metal monoxides NiO and MnO,showing remarkable agreement with experiments and highlighting the fundamental role of these newly implemented Hubbard corrections.The method holds great promise for describing collective spin excitations in complex materials containing localized electronic states.展开更多
Drawing on resource dependence theory, this paper develops and empirically tests a model for understanding how the implementation of building information modeling(BIM) in construction projects impacts the performance ...Drawing on resource dependence theory, this paper develops and empirically tests a model for understanding how the implementation of building information modeling(BIM) in construction projects impacts the performance of different project participating organizations through improving their interorganizational collaboration capabilities. Based on two sets of survey data collected from designers and general contractors in BIMbased construction projects in China, the results from partial least squares analysis and bootstrapping mediation test provide clear evidence that BIM-enabled capabilities of information sharing and collaborative decision-making as a whole play a significant role in determining BIMenabled efficiency and effectiveness benefits for both designers and general contractors. The results further reveal that designers and general contractors benefit from project BIM implementation activities significantly nonequivalently, and that this non-equivalence closely relates to the different roles played by designers and general contractors in BIM-enabled interorganizational resource exchange processes. The findings validate the resource dependence theory perspective of BIM as a boundary spanning tool to manage interorganizational resource dependence in construction projects, and contribute todeepened understandings of how and why project participating organizations benefit differently from the implementation of interorganizational information technologies like BIM.展开更多
In most cases,the redox activity of a U^(Ⅵ)O_(2)^(2+) complex is regarded as metal-centered phenomena,because uranium has small energy gaps amongst the 5f/6d/7s subshells,thereby exhibiting a wide range of oxidation ...In most cases,the redox activity of a U^(Ⅵ)O_(2)^(2+) complex is regarded as metal-centered phenomena,because uranium has small energy gaps amongst the 5f/6d/7s subshells,thereby exhibiting a wide range of oxidation states,commonly from+Ⅲ to+Ⅵ or in some cases even+I or+Ⅱ.While a wide variety of redox-active ligands are known for use as transition metal complexes including multi-electron reduction that could facilitate inert bond or small molecule activation,only a few such examples are known for U^(Ⅵ)O_(2)^(2+).In this study,three U^(Ⅵ)O_(2)^(2+)complexes bearing α-diimine-,o-quinonediimine-and 2,6-diiminopyridine-based ligands were synthesized,which exhibited two redox couples in the range of−0.79 V to−2.02 V vs.Fc+/0 to give singly-and doubly-reduced complexes by stepwise reduction.Unique electronic transitions of U^(Ⅵ)O_(2)^(2+) complexes with a variety of low-lying excited states helped us to combine spectroelectrochemistry and time-dependent density functional theory(TD-DFT)calculations which complemented each other to assign the redox-active site in these U^(Ⅵ)O_(2)^(2+) complexes,i.e.,whether or not a ligand of interest becomes redox-active.During all the redox processes observed here,the ligands employed are found to be exclusively redox-active,i.e.,non-innocent,whereas the centered U^(Ⅵ)O_(2)^(2+) is just“spectating”and remains unchanged,i.e.,innocent.Whereas the double reduction of the U^(Ⅵ)O_(2)^(2+) complexes usually involves breaking of strong UuO bonds,in the present examples this is not required and therefore a basis for the synthesis of new types of uranium molecular catalysts and magnetic materials may be found.展开更多
The geometrical structures of Wells-Dawson derivatives[X-C(CH_(2)O)_(3)P_(2)M’_(3)M_(15)O_(59)]^(6-)(X=NO_(2),NH_(2),and CH_(3),M’=V and Nb,M=W and Mo)have been calculated by the density functional theory(DFT)method...The geometrical structures of Wells-Dawson derivatives[X-C(CH_(2)O)_(3)P_(2)M’_(3)M_(15)O_(59)]^(6-)(X=NO_(2),NH_(2),and CH_(3),M’=V and Nb,M=W and Mo)have been calculated by the density functional theory(DFT)method.The results show that the distances of P…P and P…C are controlled by the{M’_(3)}triads,and{M’_(3)}triads also affect the sizes of W_(6) hexagonal belts.The second-order polarizabilities and origin of nonlinear optical(NLO)properties of those clusters have been investigated by a time-dependent density functional theory(TDDFT)method.The NLO property analysis reveals that[X-C(CH_(2)O)3P_(2)V_(3)Mo_(15)O_(59)]^(6-)(X=NH_(2))anions have the largest β_(vec) values,75.064×10^(-30) esu.Grafting electron donors to POM clusters is an efficient way to improve the NLO response.The major electron transition orbitals show that the charge transfer from the organic groups to the metal atoms is responsible for the NLO properties of these polyoxometalates.展开更多
Given the current depletion of energy resources and the escalating severity of environmental issues,it is of utmost importance to develop sustainable materials capable of detecting harmful substances and removing adve...Given the current depletion of energy resources and the escalating severity of environmental issues,it is of utmost importance to develop sustainable materials capable of detecting harmful substances and removing adverse environmental impacts.Herein,a rare-earth-free white-light-emitting MOF Cd-PNMI(PNMI,N-(4-pyridyl)-1,4,5,8-naphathalene-tetracarboxy-monoimide),deriving from an idea that involves the construction of a strong white-light-emitting MOFs using a weak white-light-emitting ligand PNMI with d^(10)metal based on ligand-to-ligand charge transfer(LLCT)luminescent mechanism,was designed and confirmed using time-dependent density functional theory(TDDFT)calculations.As a sustainable white-light-emitting material,CdPNMI can not only detect explosive and highly toxic substances at low limits of detection(LOD)but also adsorb the dyes from waste liquids.The CdPNMI emulsion demonstrated ratiometric sensing with remarkable dual-emission fluorescence quenching for nitro explosive and highly toxic substances,which was confirmed to be the result of a synergetic contribution of photo-induced electronic transfer(PET)and Förster resonance energy transfer(FRET)quenching mechanism.Due to the distinctive structure character,CdPNMI also exhibited rapid,selective and extensive adsorption for Rhodamine B(RhB)and fluorescein(FITC)dye,contributing to the elimination of these pollutants from waste liquids.展开更多
The electronic structures of a cyanide bridged Fe-Co molecular square,[Co_(2)Fe_(2)(CN)_(6)(tp*)_(2)(dtbbpy)_(4)]-(PF_(6))_(2)·2MeOH(1)(tp*=hydrotris(3,5-dimethylpyrazol-1-yl)borate,dtbbpy=4,4’-di-tert-butyl-2,2...The electronic structures of a cyanide bridged Fe-Co molecular square,[Co_(2)Fe_(2)(CN)_(6)(tp*)_(2)(dtbbpy)_(4)]-(PF_(6))_(2)·2MeOH(1)(tp*=hydrotris(3,5-dimethylpyrazol-1-yl)borate,dtbbpy=4,4’-di-tert-butyl-2,2’-bipyridine),which exhibits thermal and photo-induced two-step charge-transfer induced spin transitions(CTIST),are investigated in detail by density functional theory(DFT)and time-dependent(TD)DFT calculations.For the three phases observed in the experiment,three different model structures are constructed based on the geometries of X-ray crystallography analysis measured at low(100 K),middle(298 K)and high(330 K)temperatures.The calculated results elucidate that the ground states at the low and the high temperatures are diamagnetic[(Fe_(LS)^(Ⅱ))_(2)(Co_(LS)^(Ⅲ))_(2)]and ferromagnetic[(Fe_(LS)^(Ⅲ))_(2)(Co_(HS)^(Ⅱ))_(2)],respectively.On the other hand,the one-electron transferred[FeⅡ LSFe_(LS)^(Ⅲ)Co_(HS)^(Ⅱ)Co_(LS)^(Ⅲ)]state becomes the ground state at the intermediate temperature phase.A magnetic interaction between Fe^(Ⅲ) and Co^(Ⅱ) in the[(Fe_(LS)^(Ⅲ))_(2)(Co_(HS)^(Ⅱ))_(2)]state is ferromagnetic and the most stable spin-coupling state is the all-ferromagnetic state.The TD-DFT calculation shows the two significant peaks of Fe^(Ⅱ)t_(2g)→Co^(Ⅲ)_(eg) around 800 nm.The results support that the experimental broad absorption peak at 770 nm is an inter-valence charge transfer(IVCT)band.展开更多
The electronic circular dichroism(ECD)spectra of chiral inorganic polythioanion Möbius strip[(Mo_(2)S_(2)O_(2))_(4)(OH)_(6)(C_(4)O_(4))(Mo_(2)O_(8))]^(4−)(1a)and its 1e-and 2e-reduced forms were investigated by u...The electronic circular dichroism(ECD)spectra of chiral inorganic polythioanion Möbius strip[(Mo_(2)S_(2)O_(2))_(4)(OH)_(6)(C_(4)O_(4))(Mo_(2)O_(8))]^(4−)(1a)and its 1e-and 2e-reduced forms were investigated by using the time-dependent density functional theory(TDDFT)method.The simulated UV spectra of 1a agree well with the experimental spectra,confirming that the CAM-B3LYP hybrid functional can accurately predict the excitation energies of a polythioanion.The shapes of the ECD bands for the reduced forms are similar to that of 1a,while the rotatory strengths clearly increase with the additional electrons.The peaks in the ECD spectra of 1a are mainly assigned to the charge transfer from the{C_(4)O_(4)}unit and S atoms to the Mo and terminal oxygen(O_(t))atoms.The{C_(4)O_(4)}unit is the main chiroptical chromophore.For the reduced forms,the charge transfer from S atoms to Mo atoms significantly increases with the additional electrons.It is reasonable to assume that the transfer of chirality from the{C_(4)O_(4)}unit to the{Mo_(2)S_(2)O_(2)}unit is generated during the reduction process.展开更多
Herein,the electronic structures and electronic circular dichroism(ECD)spectra of the chiral Wells-Dawson(W-D)polyoxoanion[(L,D-C_(6)H_(10)N_(3)O_(2))P_(2)Mo_(18)O_(62)]^(5-)(1a/1b)and chiral polyoxoanion[(L,D-C_(6)H_...Herein,the electronic structures and electronic circular dichroism(ECD)spectra of the chiral Wells-Dawson(W-D)polyoxoanion[(L,D-C_(6)H_(10)N_(3)O_(2))P_(2)Mo_(18)O_(62)]^(5-)(1a/1b)and chiral polyoxoanion[(L,D-C_(6)H_(10)N_(3)O_(2))PMo_(9)O_(31)(OH_(2))_(3)]^(2-)(2a/2b)are investigated using density functional theory(DFT)and time-dependent DFT(TDDFT)calculations.Compared to the fully oxidized[P_(2)Mo_(18)O_(62)]^(6-)structure,the Mo-Ob bond lengths in the one-electron reduced state,[P_(2)Mo_(18)O_(62)]^(7-),tends to be average.It is reasonable that organic ligands can transfer electrons to POMs and affect their chirality.The energy difference between the chiral L-[P_(2)Mo_(18)O_(62)]^(6-)with D_(3)symmetry and ideal[P_(2)Mo_(18)O_(62)]^(6-)with D_(3h)symmetry is 5.88 kcal mol^(-1),which suggests that chirality inversion may occur from the L-isomer to the D-isomer through the ideal[P_(2)Mo_(18)O_(62)]^(6-)by crossing a small energy barrier.Meanwhile,the interaction energy between the L-isomer and L-histidine ligand is larger than that of L-isomer and D-histidine,which indicates that L,D-[P_(2)Mo_(18)O_(62)]^(6-)is induced and further separated by the chiral histidine.The origins of the chiral polyoxoanion are mainly ascribed to charge-transfer(CT)transitions from the O atoms to Mo atoms or organic ligands to Mo atoms.These results confirm that organic cations have an induced effect on chiral POMs.展开更多
This paper conducts a theoretical analysis of bank performance through the lens of three key theoretical perspectives:Principal-Agent Theory,Resource Dependence Theory,and Financial Innovation Theory.By examining thei...This paper conducts a theoretical analysis of bank performance through the lens of three key theoretical perspectives:Principal-Agent Theory,Resource Dependence Theory,and Financial Innovation Theory.By examining their individual contributions and the conflicts or synergies among them,the study develops an integrative framework to evaluate and enhance the performance of urban commercial banks(CCBs).The Principal-Agent Theory emphasizes the governance and incentive alignment challenges specific to financial institutions,while the Resource Dependence Theory highlights the strategic management of external resources critical for bank success.Additionally,Financial Innovation Theory underscores the importance of adapting to and leveraging innovations in the financial sector.The synthesis of these theories offers a holistic understanding of bank performance,proposing actionable strategies for governance,resource optimization,and innovation adoption.This work provides both theoretical and practical implications for policymakers,researchers,and banking practitioners aiming to improve the competitive positioning and efficiency of urban commercial banks.展开更多
基金supported by the Center for Advanced Systems Understanding(CASUS),financed by Germany’s Federal Ministry of Education and Research(BMBF)and the Saxon State Government out of the State Budget approved by the Saxon State Parliamentfunding from the European Research Council(ERC)under the European Union’s Horizon 2022 research and innovation programme(Grant Agreement No.101076233,“PREXTREME”)funding from the European Union’s Just Transition Fund(JTF)within the project Röntgenlaser-Optimierung der Laserfusion(ROLF),Contract No.5086999001,co-financed by the Saxon State Government out of the State Budget approved by the Saxon State Parliament.
文摘Ab initio modeling of dynamic structure factors(DSF)and related density response properties in the warm dense matter(WDM)regime is a challenging computational task.The DSF,convolved with a probing X-ray beam and instrument function,is measured in X-ray Thom-son scattering(XRTS)experiments,which allow the study of electronic structure properties at the microscopic level.Among the various ab initio methods,linear-response time-dependent density-functional theory(LR-TDDFT)is a key framework for simulating the DSF.The standard approach in LR-TDDFT for computing the DSF relies on the orbital representation.A significant drawback of this method is the unfavorable scaling of the number of required empty bands as the wavenumber increases,making LR-TDDFT impractical for modeling XRTS measurements over large energy scales,such as in backward scattering geometry.In this work,we consider and test an alternative approach to LR-TDDFT that employs the Liouville–Lanczos(LL)method for simulating the DSF of WDM.This approach does not require empty states and allows the DSF at large momentum transfer values and over a broad frequency range to be accessed.We compare the results obtained from the LL method with those from the solution of Dyson’s equation using the standard LR-TDDFT within the projector augmented-wave formalism for isochorically heated aluminum and warm dense hydrogen.Additionally,we utilize exact path integral Monte Carlo results for the imaginary-time density-density correlation function(ITCF)of warm dense hydrogen to rigorously benchmark the LL approach.We discuss the application of the LL method for calculating DSFs and ITCFs at different wavenumbers,the effects of pseudopotentials,and the role of Lorentzian smearing.The successful validation of the LL method under WDM conditions makes it a valuable addition to the ab initio simulation landscape,supporting experimental efforts and advancing WDM theory.
文摘Based on spin-unrestricted hartree fock theory, we present the spin unrestricted multi- configuration time dependent hartree lock theory （UMCTDHF） to describe the electron correlation dynamics of systems interacting with laser field. The positive spin orbitals and the negative spin orbitals are propagated in their own subspace respectively. The spin orbital in the spin-down subspace acts with that in the spin-up subspace by the reduced density matrix and mean field operator. The ground energy is acquired by propagating the trial wave function in the imaginary time by using spin-restricted MCTDHF （RMCTDHF） and UMCTDHF respectively. Then the ionization probabilities and the electrons energies are calculated by using RMCTDHF and UMCTDHF when the laser field is present. The ionization probability calculated with UMCTDHF agrees with the previous theoretical reports very well. The UMCTDHF method is accurate and applicable for open shell system beyond the capability of the RMCTDHF method.
文摘A series of blue and blue‑green Ir(Ⅲ)complexes has been investigated theoretically to explore their electronic structures,photophysical properties,efficiency roll‑off effect,and thermal activation delayed fluorescence(TADF)properties.All calculations were performed using density functional theory(DFT)and time‑dependent density functional theory(TDDFT).Calculations for electronic structures,frontier molecular orbital characteristics(which determine the efficiency roll‑off effect of the complexes),and photophysical properties were conducted using the Gaussian 09 software package.The calculation of spin‑orbit coupling matrix elements<T|HSOC|S>,which determine the TADF properties of the complexes,was performed using the ORCA software package.The calculation results show that the auxiliary ligand tetraphenylimidodiphosphinate(tpip),a strong electron‑withdrawing group,can mitigate the efficiency roll‑off effect of the complex.Furthermore,TADF is observed in one of the designed complexes,(F_(3)Phppy)_(2)Ir(tpip),where F_(3)Phppy=2‑[4‑(2,4,6‑trifluorophenyl)phenyl]pyridine.
基金Project supported by the National Natural Science Foundation of China(55791020)
文摘Time dependent nucleation theory was applied to calculate the incubation time required for α Al nucleation in rapid solidified (RS) Al Fe V Si Nd alloys. The nucleation rates were calculated as a function of temperature, and the critical cooling rates required for the formation of amorphous α Al at different neodymium concentrations were calculated too. The addition of neodymium increases the amorphizablity of α Al by increasing the incubation time and decreasing the nucleation rate and the critical cooling rate. The calculations are fitted to experimental results when liquidus temperatures are estimated from an approximation, which treats Al Fe V Si Nd as quasi binary Al Fe system.
文摘Radio is all about dreams. This old and tired medium now fights with new media as it is with its old enemy television. Radio has a big impact on dreams. It gives you the sound and makes you dream. Once you get used to this media you start dreaming. If you used to listen radio more, you get in dependence with it. So this day dreaming change to lifeless dreaming. This article gives an evaluation of how radio audience can shape audience future dreams with dependence theory. The paper starts with a conceptual explanation of dependence theory and goes on with a survey done in Turkey to 101 radio listeners. The survey investigates on how people like listening the radio and what makes them enjoy radio. The survey assumes that people listening to radio and getting depended on it start changing the behaviors and habits of listeners. This behavior change effects listeners future dreams and the audience take radio as a model. The paper shows by using the dependence theory that radio listeners take the radio they love as model and use it to build their future business dreams.
基金Research on the Impact of Navel Orange Industry Development on the Ecological Environment and Its Countermeasures(Project from Jiangxi Provincial Department of Science and Technology,2012BBF60185,Second Principal Investigator:Jinqiao Ling)Research on the Reform of Cultural Foundational Courses in Vocational Colleges and the Cultivation of Students’Professional Quality(Provincial Social Science Project,JXJGYX-2011-32,Second Principal Investigator:Jinqiao Ling)Research on Promoting Green Ecological Creation in Ganzhou(Ganzhou Federation of Social Sciences Circles,JXGZ-2010-09,Principal Investigator:Jinqiao Ling).
文摘As the Sarawak state government accelerates infrastructure development to stimulate economic growth,it has attracted numerous foreign construction enterprises-particularly Chinese firms-entering the market through low-cost bidding.However,this foreign-dominated model,while improving efficiency,has triggered local enterprise marginalization,industrial chain fragmentation,payment delays,and project setbacks,undermining the intended economic spillover effects of public investment.Grounded in policy analysis and field evidence within a dependency theory framework,this study evaluates the structural impacts of foreign participation on Sarawak’s local economy,uncovers governance gaps,and proposes strategies to enhance local economic resilience under open-market conditions.The findings reveal that foreign contractors(especially Chinese enterprises),despite their capital and technological advantages in dominating mega-projects,exhibit pervasive shortcomings:inadequate local participation(falling far below the 40%policy target),deficient knowledge transfer(local firms hold only 6%of green technology patents),significant value leakage(foreign profit repatriation dominated project value flows),and widespread execution delays/cost overruns due to underestimation of tropical climate-geological risks,institutional maladaptation,and resource misallocation.Drawing on experiences from the Philippines,Indonesia,and Vietnam,the study proposes systemic reforms:introducing a Low-Bid Risk Evaluation System(LRES),enforcing a mandatory Local Participation Index(LPI),establishing a Smart-Contract-Based Digital Payment Chain System(DPCS)to protect subcontractors,and requiring pre-bid local adaptation training for foreign contractors.These recommendations aim to construct“embedded institutional resilience,”transforming policy intent into executable governance mechanisms to ensure infrastructure investment genuinely serves Sarawak’s inclusive and sustainable growth.
基金supported by the Fundamental Research Funds for the Central Universities(Grant Nos.GK202207012 and QCYRCXM-2022-241).
文摘Permanent dipole moments induced high-order harmonic generation(HHG)signals offer a potential approach to producing elliptically or even circularly polarized X-ray attosecond sources.Previous studies on this topic have mainly focused on diatomic molecules such as CO and HeH.Based on this scheme,significant HHG signals in the direction perpendicular to the molecular axis can be observed in both the high-energy and low-energy regions.However,we found that the high-order harmonics induced by the permanent dipole moments of polyatomic complex molecules involve more intricate physical processes.Using time-dependent density functional theory,we simulated the dynamics of HHG from NH2COOH and NH2COSH interacting with linearly polarized lasers.We found that the harmonic signals in the direction perpendicular to the N-C bond were significantly enhanced in the high-energy photon region.Our analysis indicates that this is due to the complex molecular configuration of NH_(2)COOH and NH_(2)COSH:while the NH_(2) group has C_(2v) symmetry,both COOH and COSH groups lack this symmetry.This structural characteristic results in permanent dipole moments being felt only when electrons return to either COSH or COOH groups,but not to NH_(2) group.Additionally,our results reveal a multi-plateau structure in HHG signal along laser polarization direction,a phenomenon arising from multi-electron and multiorbital effects during interaction between complex molecule and strong laser field.
文摘Orthodox quantum mechanics is a highly successful theory despite its serious conceptual flaws. It renounces realism, implies a kind of action-at-a-distance and is incompatible with determinism. Orthodox quantum mechanics states that Schrödinger’s equation (a deterministic law) governs spontaneous processes while measurement processes are ruled by probability laws. It is well established that time dependent perturbation theory must be used for solving problems involving time. In order to account for spontaneous processes, this last theory makes use of laws valid only when measurements are performed. This incoherence seems absent from the literature.
文摘The study of various oxidation states of chromium with Sargassum <i>sp</i>. is of particular interest since hexavalent chromium </span><span style="font-size:10.0pt;font-family:"">is </span><span style="font-size:10.0pt;font-family:"">reduced to trivalent chromium in </span><span style="font-size:10.0pt;font-family:"">an </span><span style="font-size:10.0pt;font-family:"">aqueous solution. In this study, a systematic density functional theory (DFT) calculations were performed to study the interactions of transition metal chromium ion with different oxidation states and spin states with the <i>Sar</i></span><i><span style="font-size:10.0pt;font-family:"">gassum sp</span></i><span style="font-size:10.0pt;font-family:"">. decorated with carboxylate</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">(acetate) at the wB97XD/6-311++</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">G(d,p)</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">level of theory. The structures and binding energies of chromium met<span>al</span></span><span style="font-size:10.0pt;font-family:"">-</span><span style="font-size:10.0pt;font-family:"">carboxylate complexes at various oxidation states and spin states in gas</span><span style="font-size:10.0pt;font-family:""> phase were examined. The coordination strength of Cr(VI) with the acetate <span>ligand was predominantly the strongest compare</span></span><span style="font-size:10.0pt;font-family:"">d</span><span style="font-size:10.0pt;font-family:""> to the other oxidation</span><span style="font-size:10.0pt;font-family:""> states. <span>Vibrational frequency analysis, for the homoleptic monomers of tris</span> <span>[</span><span>Cr<sup>III</sup>(AC)<sub>3</sub>]<sup>0</sup> and </span>[Cr<sup>VI</sup>(AC)<sub>3</sub>]<sup>3+</sup> complexes, illustrate good harmony with the experimental and<span> theoretical calculated frequencies. Using the time</span></span><span style="font-size:10.0pt;font-family:"">-</span><span style="font-size:10.0pt;font-family:"">dependent DFT</span><span style="font-size:10.0pt;font-family:""> (TD-DFT) at the level of CAM-B3LYP/6-311++G(d,p), the vertical excitation energies were obtained. The stabilization energies derived using the second order perturbation </span><span style="font-size:10.0pt;font-family:"">theory, <i>E</i><sub>ij</sub><sup>(2)</sup>, of NBO analysis confirmed the greater charge transfer for the</span><span style="font-size:10.0pt;font-family:""> observed trends in the metal binding. The calculated binding </span><span style="font-size:10.0pt;font-family:"">energies</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">(ΔE) and interactions energies </span><span style="font-size:10.0pt;font-family:Symbol;">S</span><i><span style="font-size:10.0pt;font-family:"">E</span></i><sub><span style="font-size:10.0pt;font-family:"">ij</span></sub><sup><span style="font-size:10.0pt;font-family:"">(2)</span></sup><span style="font-size:10.0pt;font-family:""> favor</span><span style="font-size:10.0pt;font-family:""> </span><span style="font-size:10.0pt;font-family:"">the formation of</span><span style="font-size:10.0pt;font-family:""> [Cr<sup>VI</sup>(AC)<sub>3</sub>]<sup>3+</sup> complexes. The findings of this study identify efficient electronic factors as major contributors to the metal binding affinities, with promising possibilities for the design of metal-ligand complexes and sensing of the metal ions.
基金Chongqing Social Science Cultivation Project—Empirical Research on the Development of Community-Based Social Organizations'Capacity in the Process of Shifting the Focus of Social Governance to the Grassroots(2021PY21)Chongqing Social Science Planning Project—Research on Collaborative Prevention Mechanisms for Social Risk Governance in Chongqing(2024NDYB105)Chongqing May Day Vocational and Technical College—Research on the Current Status and Pathways of Social Work Participation in Urban and Regional Grassroots Governance(KY2024102).
文摘Community-based social organizations play a vital role in grassroots governance but generally face resource dependence dilemmas that constrain their capacity building and sustainable development.Based on Resource Dependence Theory(RDT),this study addresses the limitations of existing research,such as the lack of an integrated framework and insufficient exploration of bidirectional interaction mechanisms,by systematically analyzing the current state of resource dependence among community-based social organizations.The study constructs a three-dimensional capacity-building strategy:optimizing dependency structures through the establishment of a diversified resource supply network;enhancing resource acquisition capabilities through identification,integration,and utilization of resources;and cultivating organizational autonomy through governance structures,professional competencies,and organizational culture.These strategies provide both theoretical support and practical pathways for community-based social organizations to overcome resource constraints and achieve sustainable development.
基金supported by JSPS KAKENHI Grant Numbers JP20K14382 and JP21H01842the Cluster of Excellence 'CUI: Advanced Imaging of Matter'- EXC 2056 - project ID 390715994+5 种基金SFB-925 "Light induced dynamics and control of correlated quantum systems" – project 170620586 of the Deutsche Forschungsgemeinschaft (DFG)the Max Planck-New York City Center for Non-Equilibrium Quantum PhenomenaThis work was also supported by MEXT Promotion of Development of a Joint Usage/ Research System Project: Coalition of Universities for Research Excellence Program (CURE) Grant Number JPMXP1323015474We also acknowledge support from the Marie Sk{\l}odowska- Curie Doctoral Network TIMES, grant No. 101118915, and SPARKLE grant No. 101169225the Italian Ministry of University and Research (MUR) under the PRIN 2022 Grant No 2022PX279E_003Next Generation EUPartenariato Esteso NQSTI - Spoke 2 (THENCE-PE00000023). The Flatiron Institute is a division of the Simons Foundation. This work used computational resources of the HPC systems at the Max Planck Computing and Data Facility (MPCDF), and the Fujitsu PRIMERGY CX400M1/CX2550M5 (Oakbridge-CX) at the Information Technology Center, the University of Tokyo through the HPCI System Research Project (Project ID:hp220112).
文摘First-principles electron dynamics calculations can be applied in the investigation of a wide range of ultrafast phenomena in attosecond physics.They offer unique microscopic insight into light-induced ultrafast phenomena in both gas and condensed phases of matter,and thus,they are apowerful tool to develop our understanding of the physics of attosecond phenomena.We specifically review techniques employing time-dependent density functional theory(TDDFT)for investigating attosecond and strong-field phenomena.First,we describe this theoretical framework that enables the modeling of perturbative and non-perturbative electron dynamics in materials,including atoms,molecules,and solids.We then discuss its application to attosecond experiments,focusing on the reconstruction of attosecond beating by interference of two-photon transitions(RABBIT)measurements.Wealso briefly review first-principles calculations of optical properties of solids with TDDFT in the linear response regime and their extension to calculations of transient optical properties of solids in non-equilibrium phases,by simulating experimental pump-probe setups.We further demonstrate the application of TDDFT simulation to high-order harmonic generation in solids.First-principles calculations have predictive power,and hence they can be utilized to design future experiments to explore nonequilibrium and nonlinear ultrafast phenomena in matter and characterize and control metastable light-induced quantum states.
基金support by the NCCR MARVEL,a National Centre of Competence in Research,funded by the Swiss National Science Foundation(Grant number 205602)the Fellowship from the EPFL QSE Center“Many-body neural simulations of quantum materials”(Grant number 10060)supported by a grant from the Swiss National Supercomputing Centre(CSCS)under project ID s1073 and mr33(Piz Daint).
文摘Spin excitations play a fundamental role in understanding magnetic properties of materials,and have significant technological implications for magnonic devices.However,accurately modeling these in transition-metal and rare-earth compounds remains a formidable challenge.Here,we present a fully first-principles approach for calculating spin-wave spectra based on time-dependent(TD)density-functional perturbation theory(DFPT),using nonempirical Hubbard functionals.This approach is implemented in a general noncollinear formulation,enabling the study of magnons in both collinear and noncollinear magnetic systems.Unlike methods that rely on empirical Hubbard U parameters to describe the ground state,and Heisenberg Hamiltonians for describing magnetic excitations,the methodology developed here probes directly the dynamical spin susceptibility(efficiently evaluated with TDDFPT throught the Liouville-Lanczos approach),and treats the linear variation of the Hubbard augmentation(in itself calculated non-empirically)in full at a self-consistent level.Furthermore,the method satisfies the Goldstone condition without requiring empirical rescaling of the exchange-correlation kernel or explicit enforcement of sum rules,in contrast to existing state-of-the-art techniques.We benchmark the novel computational scheme on prototypical transition-metal monoxides NiO and MnO,showing remarkable agreement with experiments and highlighting the fundamental role of these newly implemented Hubbard corrections.The method holds great promise for describing collective spin excitations in complex materials containing localized electronic states.
基金supported by the Public Policy Research Funding Scheme in Hong Kong (Grant No. 2014. A6.054.15B)the National Natural Science Foundation of China (Grant No. 71272046)
文摘Drawing on resource dependence theory, this paper develops and empirically tests a model for understanding how the implementation of building information modeling(BIM) in construction projects impacts the performance of different project participating organizations through improving their interorganizational collaboration capabilities. Based on two sets of survey data collected from designers and general contractors in BIMbased construction projects in China, the results from partial least squares analysis and bootstrapping mediation test provide clear evidence that BIM-enabled capabilities of information sharing and collaborative decision-making as a whole play a significant role in determining BIMenabled efficiency and effectiveness benefits for both designers and general contractors. The results further reveal that designers and general contractors benefit from project BIM implementation activities significantly nonequivalently, and that this non-equivalence closely relates to the different roles played by designers and general contractors in BIM-enabled interorganizational resource exchange processes. The findings validate the resource dependence theory perspective of BIM as a boundary spanning tool to manage interorganizational resource dependence in construction projects, and contribute todeepened understandings of how and why project participating organizations benefit differently from the implementation of interorganizational information technologies like BIM.
基金supported in part by the Grants-in-Aid for Scientific Research(Grant No.20H02663 to KT,and 21J11942 to TT)of the Japan Society for the Promotion for Science(JSPS)the JAEA Nuclear Energy S&T and the Human Resource Development Project through concentrating wisdom(Grant No.JPJA19P19209861)the International Research Frontiers Initiative(IRFI)of Institute of Innovative Research,Tokyo Institute of Technology.
文摘In most cases,the redox activity of a U^(Ⅵ)O_(2)^(2+) complex is regarded as metal-centered phenomena,because uranium has small energy gaps amongst the 5f/6d/7s subshells,thereby exhibiting a wide range of oxidation states,commonly from+Ⅲ to+Ⅵ or in some cases even+I or+Ⅱ.While a wide variety of redox-active ligands are known for use as transition metal complexes including multi-electron reduction that could facilitate inert bond or small molecule activation,only a few such examples are known for U^(Ⅵ)O_(2)^(2+).In this study,three U^(Ⅵ)O_(2)^(2+)complexes bearing α-diimine-,o-quinonediimine-and 2,6-diiminopyridine-based ligands were synthesized,which exhibited two redox couples in the range of−0.79 V to−2.02 V vs.Fc+/0 to give singly-and doubly-reduced complexes by stepwise reduction.Unique electronic transitions of U^(Ⅵ)O_(2)^(2+) complexes with a variety of low-lying excited states helped us to combine spectroelectrochemistry and time-dependent density functional theory(TD-DFT)calculations which complemented each other to assign the redox-active site in these U^(Ⅵ)O_(2)^(2+) complexes,i.e.,whether or not a ligand of interest becomes redox-active.During all the redox processes observed here,the ligands employed are found to be exclusively redox-active,i.e.,non-innocent,whereas the centered U^(Ⅵ)O_(2)^(2+) is just“spectating”and remains unchanged,i.e.,innocent.Whereas the double reduction of the U^(Ⅵ)O_(2)^(2+) complexes usually involves breaking of strong UuO bonds,in the present examples this is not required and therefore a basis for the synthesis of new types of uranium molecular catalysts and magnetic materials may be found.
基金financial support by NSFC(20971020,21073030 and 21131001)Program for New Century Excellent Talents in University(NCET-10-318)+1 种基金Doctoral Fund of Ministry of Education of China(20100043120007)the Science and Technology Development Planning of Jilin Province(20100104 and 20100320).
文摘The geometrical structures of Wells-Dawson derivatives[X-C(CH_(2)O)_(3)P_(2)M’_(3)M_(15)O_(59)]^(6-)(X=NO_(2),NH_(2),and CH_(3),M’=V and Nb,M=W and Mo)have been calculated by the density functional theory(DFT)method.The results show that the distances of P…P and P…C are controlled by the{M’_(3)}triads,and{M’_(3)}triads also affect the sizes of W_(6) hexagonal belts.The second-order polarizabilities and origin of nonlinear optical(NLO)properties of those clusters have been investigated by a time-dependent density functional theory(TDDFT)method.The NLO property analysis reveals that[X-C(CH_(2)O)3P_(2)V_(3)Mo_(15)O_(59)]^(6-)(X=NH_(2))anions have the largest β_(vec) values,75.064×10^(-30) esu.Grafting electron donors to POM clusters is an efficient way to improve the NLO response.The major electron transition orbitals show that the charge transfer from the organic groups to the metal atoms is responsible for the NLO properties of these polyoxometalates.
基金supported by the Natural Science Foundation of Shanxi Province(20210302124253).
文摘Given the current depletion of energy resources and the escalating severity of environmental issues,it is of utmost importance to develop sustainable materials capable of detecting harmful substances and removing adverse environmental impacts.Herein,a rare-earth-free white-light-emitting MOF Cd-PNMI(PNMI,N-(4-pyridyl)-1,4,5,8-naphathalene-tetracarboxy-monoimide),deriving from an idea that involves the construction of a strong white-light-emitting MOFs using a weak white-light-emitting ligand PNMI with d^(10)metal based on ligand-to-ligand charge transfer(LLCT)luminescent mechanism,was designed and confirmed using time-dependent density functional theory(TDDFT)calculations.As a sustainable white-light-emitting material,CdPNMI can not only detect explosive and highly toxic substances at low limits of detection(LOD)but also adsorb the dyes from waste liquids.The CdPNMI emulsion demonstrated ratiometric sensing with remarkable dual-emission fluorescence quenching for nitro explosive and highly toxic substances,which was confirmed to be the result of a synergetic contribution of photo-induced electronic transfer(PET)and Förster resonance energy transfer(FRET)quenching mechanism.Due to the distinctive structure character,CdPNMI also exhibited rapid,selective and extensive adsorption for Rhodamine B(RhB)and fluorescein(FITC)dye,contributing to the elimination of these pollutants from waste liquids.
基金supported by Grant-in-Aid for Scientific Research(KAKENHI)(C)(no.26410093)from the Japan Society for the Promotion of Science(JSPS)Grant-in-Aid for Scientific Research on Innovative Areas(“Coordination programming”,no.24108721)from the Ministry of Education,Culture,Sports,Science and Technology(MEXT)the Inter-University Cooperative Research Program of the Institute for Materials Research,Tohoku University(proposal no.14K0008,15K0118).
文摘The electronic structures of a cyanide bridged Fe-Co molecular square,[Co_(2)Fe_(2)(CN)_(6)(tp*)_(2)(dtbbpy)_(4)]-(PF_(6))_(2)·2MeOH(1)(tp*=hydrotris(3,5-dimethylpyrazol-1-yl)borate,dtbbpy=4,4’-di-tert-butyl-2,2’-bipyridine),which exhibits thermal and photo-induced two-step charge-transfer induced spin transitions(CTIST),are investigated in detail by density functional theory(DFT)and time-dependent(TD)DFT calculations.For the three phases observed in the experiment,three different model structures are constructed based on the geometries of X-ray crystallography analysis measured at low(100 K),middle(298 K)and high(330 K)temperatures.The calculated results elucidate that the ground states at the low and the high temperatures are diamagnetic[(Fe_(LS)^(Ⅱ))_(2)(Co_(LS)^(Ⅲ))_(2)]and ferromagnetic[(Fe_(LS)^(Ⅲ))_(2)(Co_(HS)^(Ⅱ))_(2)],respectively.On the other hand,the one-electron transferred[FeⅡ LSFe_(LS)^(Ⅲ)Co_(HS)^(Ⅱ)Co_(LS)^(Ⅲ)]state becomes the ground state at the intermediate temperature phase.A magnetic interaction between Fe^(Ⅲ) and Co^(Ⅱ) in the[(Fe_(LS)^(Ⅲ))_(2)(Co_(HS)^(Ⅱ))_(2)]state is ferromagnetic and the most stable spin-coupling state is the all-ferromagnetic state.The TD-DFT calculation shows the two significant peaks of Fe^(Ⅱ)t_(2g)→Co^(Ⅲ)_(eg) around 800 nm.The results support that the experimental broad absorption peak at 770 nm is an inter-valence charge transfer(IVCT)band.
基金financial support from NSFC(21403033,21203020)the Science and Technology Development Planning of Jilin Province(201201067).
文摘The electronic circular dichroism(ECD)spectra of chiral inorganic polythioanion Möbius strip[(Mo_(2)S_(2)O_(2))_(4)(OH)_(6)(C_(4)O_(4))(Mo_(2)O_(8))]^(4−)(1a)and its 1e-and 2e-reduced forms were investigated by using the time-dependent density functional theory(TDDFT)method.The simulated UV spectra of 1a agree well with the experimental spectra,confirming that the CAM-B3LYP hybrid functional can accurately predict the excitation energies of a polythioanion.The shapes of the ECD bands for the reduced forms are similar to that of 1a,while the rotatory strengths clearly increase with the additional electrons.The peaks in the ECD spectra of 1a are mainly assigned to the charge transfer from the{C_(4)O_(4)}unit and S atoms to the Mo and terminal oxygen(O_(t))atoms.The{C_(4)O_(4)}unit is the main chiroptical chromophore.For the reduced forms,the charge transfer from S atoms to Mo atoms significantly increases with the additional electrons.It is reasonable to assume that the transfer of chirality from the{C_(4)O_(4)}unit to the{Mo_(2)S_(2)O_(2)}unit is generated during the reduction process.
基金financial support by NSFC(21403033 and 21571031)。
文摘Herein,the electronic structures and electronic circular dichroism(ECD)spectra of the chiral Wells-Dawson(W-D)polyoxoanion[(L,D-C_(6)H_(10)N_(3)O_(2))P_(2)Mo_(18)O_(62)]^(5-)(1a/1b)and chiral polyoxoanion[(L,D-C_(6)H_(10)N_(3)O_(2))PMo_(9)O_(31)(OH_(2))_(3)]^(2-)(2a/2b)are investigated using density functional theory(DFT)and time-dependent DFT(TDDFT)calculations.Compared to the fully oxidized[P_(2)Mo_(18)O_(62)]^(6-)structure,the Mo-Ob bond lengths in the one-electron reduced state,[P_(2)Mo_(18)O_(62)]^(7-),tends to be average.It is reasonable that organic ligands can transfer electrons to POMs and affect their chirality.The energy difference between the chiral L-[P_(2)Mo_(18)O_(62)]^(6-)with D_(3)symmetry and ideal[P_(2)Mo_(18)O_(62)]^(6-)with D_(3h)symmetry is 5.88 kcal mol^(-1),which suggests that chirality inversion may occur from the L-isomer to the D-isomer through the ideal[P_(2)Mo_(18)O_(62)]^(6-)by crossing a small energy barrier.Meanwhile,the interaction energy between the L-isomer and L-histidine ligand is larger than that of L-isomer and D-histidine,which indicates that L,D-[P_(2)Mo_(18)O_(62)]^(6-)is induced and further separated by the chiral histidine.The origins of the chiral polyoxoanion are mainly ascribed to charge-transfer(CT)transitions from the O atoms to Mo atoms or organic ligands to Mo atoms.These results confirm that organic cations have an induced effect on chiral POMs.
文摘This paper conducts a theoretical analysis of bank performance through the lens of three key theoretical perspectives:Principal-Agent Theory,Resource Dependence Theory,and Financial Innovation Theory.By examining their individual contributions and the conflicts or synergies among them,the study develops an integrative framework to evaluate and enhance the performance of urban commercial banks(CCBs).The Principal-Agent Theory emphasizes the governance and incentive alignment challenges specific to financial institutions,while the Resource Dependence Theory highlights the strategic management of external resources critical for bank success.Additionally,Financial Innovation Theory underscores the importance of adapting to and leveraging innovations in the financial sector.The synthesis of these theories offers a holistic understanding of bank performance,proposing actionable strategies for governance,resource optimization,and innovation adoption.This work provides both theoretical and practical implications for policymakers,researchers,and banking practitioners aiming to improve the competitive positioning and efficiency of urban commercial banks.
