Herein, we employed a combination of static electronic structure calculations and nonadiabatic dynamics simulations at linear-response time dependent density functional theory (LR-TDDFT) level with the optimally tuned range-separated hybrid (OT-RSH) functional to explore the ultrafast photoinduced dynamics of a zinc phthalocyanine-benzoperylenetriimide (ZnPc-BPTI) conjugate. Due to the flexibility of the linker, we identified two major conformations: the stacked conformation (ZnPc-BPTI-1) and the extended conformation (ZnPc-BPTI-2). Since the charge transfer states are much lower than the lowest local excitation in ZnPc-BPTI-1, which is contrary to ZnPc-BPTI-2, the ultrafast electron transfer (~3.
View Article and Find Full Text PDFThe investigation into the interfacial properties between fullerene compounds and Sn-based perovskites (Sn-PVSK) holds extraordinary significance for advancing efficient and stable Pb-free perovskite solar cells. This study is the first theoretical exploration to examine their interfacial properties using Ab initio molecular dynamics (AIMD) simulations and trajectory analysis methods with C60@FASnI as a representative system. The impact of surface termination and FA rotation on interface stability has been assessed.
View Article and Find Full Text PDFElectrocatalytic CO reduction serves as an effective strategy to tackle energy crises and mitigate greenhouse gas effects. The development of efficient and cost-effective electrocatalysts has been a research hotspot in the field. In this study, we designed four Co-doped single-atom catalysts (Co-N@C) using carbon nanotubes as carriers, these catalysts included tri- and dicoordinated N-doped carbon nanoribbons, as well as tri- and dicoordinated N-doped graphene, respectively denoted as H3(H2)-Co/CNT and 3(2)-Co/CNT.
View Article and Find Full Text PDFWe have employed the highly accurate multistate complete active space second-order perturbation theory (MS-CASPT2) method to investigate the photoinduced excited state relaxation properties of one unnatural base, namely Z. Upon excitation to the S state of Z, the internal conversion to the S state would be dominant. From the S state, two intersystem crossing paths leading to the T and T states and one internal conversion path to the S state are possible.
View Article and Find Full Text PDFHerein, we have employed a combination of the optimally tuned screened range-separated hybrid (OT-SRSH) functional, the polarizable continuum model (PCM), and nonadiabatic dynamics (NAMD) simulations to investigate the photoinduced dynamics of directly linked donor-acceptor dyads formed using zinc phthalocyanine (ZnPc) and perylenediimide (PDI), in which ZnPc is the donor while PDI is the acceptor. Our simulations aim to analyze the behavior of these dyads upon local excitation of the ZnPc moiety in the gas phase and in benzonitrile. Our findings indicate that the presence of a solvent can significantly influence the excited state dynamics of ZnPc-PDI dyads.
View Article and Find Full Text PDFContext: In this paper, the adsorption characteristics of five sulfonamide antibiotic molecules on carbon nanotubes were investigated using density functional theory (DFT) calculations. The adsorption configurations of different adsorption sites were optimized, and the most stable adsorption configuration of each sulfonamide molecule was determined by adsorption energy comparison, and the relative adsorption stability of five sulfonamide molecules on carbon nanotubes was determined by comparing their adsorption energies, i.e.
View Article and Find Full Text PDFHerein, we employed a developed linear response time dependent density functional theory-based nonadiabatic dynamics simulation method that explicitly takes into account the excitonic effects to investigate photoinduced excitation energy transfer dynamics of a double-walled carbon nanotube (CNT) model with different excitation energies. The E excitation of the outer CNT will generate a local excitation (LE) |out*〉 exciton due to its low energy, which does not induce any charge separation. In contrast, the E excitation of the inner CNT can generate four kinds of excitons with the LE exciton |in*〉 dominates.
View Article and Find Full Text PDFThe decomposition of ammonia borane (NHBH) to produce hydrogen has developed a promising technology to alleviate the energy crisis. In this paper, metal and non-metal diatom-doped CoP as catalyst was applied to study hydrogen evolution from NHBH by density functional theory (DFT) calculations. Herein, five catalysts were investigated in detail: pristine CoP, Ni- and N-doped CoP (CoP), Ga- and N-doped CoP (CoP), Ni- and S-doped CoP (CoP), and Zn- and S-doped CoP (CoP).
View Article and Find Full Text PDFHerein, we have employed linear-response time dependent density functional theory (LR-TDDFT)-based nonadiabatic dynamics simulations to investigate the ultrafast charge transfer in a nonfullerene all-small-molecule donor-acceptor (D-A) system formed by a porphyrin small-molecule donor ZnP and a recently developed nonfullerene small-molecule acceptor 6TIC, during which the optimally tuned range-separated hybrid (OT-RSH) functional was adopted. In combination with static electronic structure calculations, several important conclusions were drawn. Firstly, the ZnP and 6TIC are more likely combined together non-covalently in parallel rather than in perpendicular to form ZnP-6TIC due to the much larger adsorption energies, -44.
View Article and Find Full Text PDFIn this work, eight van der Waals heterojunctions based on CdSe or CdSe-ZnS quantum dots (QDs) and four commonly used two-dimensional transition metal dichalcogenides (2D-TMDs) are theoretically designed. On the basis of the constructed structures, density functional theory (DFT) method is employed to investigate the structural and optoelectronic related properties of these heterojunctions in detail. Specifically, their electronic properties including charge density differences, density of states, and band offsets are calculated, based on which band alignment types as well as their potentials as novel photovoltaic materials are discussed.
View Article and Find Full Text PDFRecently, experimentalists have developed a green and efficient method to synthesize pyrazole-fused quinones through light-induced tetrazole-quinone 1,3-dipole cycloadditions. However, the underlying microscopic mechanisms remain to be clarified. In this work, we have employed several electronic structure calculation methods (MS-CASPT2, CASSCF, DFT) to systematically explore the microscopic mechanism of related light-induced reactions and deactivation pathways.
View Article and Find Full Text PDFUnraveling the photogenerated exciton dynamics of π-stacked molecular aggregates is of great importance for both fundamental studies and industrial applications. Among various π-stacked molecular aggregates, perylene tetracarboxylic acid bisimide (PBI) based aggregates are regarded as one of the prototypes due to their inherent high fluorescence quantum yield and excellent photostability and flexibility in controlling intermolecular forces chemical modifications. However, the exciton dynamics of these PBI based aggregates remain elusive up to now.
View Article and Find Full Text PDFIn this paper, density functional theory (DFT) and time-dependent density functional theory (TDDFT) are used to study the complexation characteristics CdTe QDs with four different capping agents, i.e. 3-mercaptopropionic acid (MPA), reduced glutathione (GSH), 1-thioglycerol (TG) and 2-mercaptoethanesulfonate (MES).
View Article and Find Full Text PDFNucleoside-based diarylethenes are emerging as an especial class of photochromic compounds that have potential applications in regulating biological systems using noninvasive light with high spatio-temporal resolution. However, relevant microscopic photochromic mechanisms at atomic level of these novel diarylethenes remain to be explored. Herein, we have employed static electronic structure calculations (MS-CASPT2//M06-2X, MS-CASPT2//SA-CASSCF) in combination with non-adiabatic dynamics simulations to explore the related photoinduced ring-closing reaction of a typical nucleoside-based diarylethene photoswitch, namely, PS-IV.
View Article and Find Full Text PDFvan der Waals heterojunctions formed by transition metal dichalcogenides (TMDs) and fullerenes are promising candidates for novel photovoltaic devices due to the excellent optoelectronic properties of both TMDs and fullerenes. However, relevant experimental and theoretical investigations remain scarce to the best of our knowledge. Herein, we have first employed static density functional theory (DFT) calculations in combination with time-domain density functional theory (TDDFT) based nonadiabatic dynamics simulations to rationally evaluate the photovoltaic performances of four TMD@fullerene heterostructures, i.
View Article and Find Full Text PDFIn order to expand the application of CO anion radical (CO), as a novel green reductant in the control of environmental pollution, CO radical was induced into the reduction of nitrate. The reduction efficiency, products and mechanism of nitrate or nitrite by CO radical were investigated based on the results of batch experiments and theoretical calculation using density functional theory (DFT) methods, respectively. It was found that: (1) the efficiency of nitrate reduction by CO radical from the HCOOH/UV system was far lower than that of nitrite under the same reaction conditions, (2) the rate-control step of nitrate reduction by CO radical was the transformation process of nitrate into nitrite with an activation energy of 23.
View Article and Find Full Text PDFThe adsorption characteristics and degradation mechanism of tinidazole on TiO(101) and (001) surfaces under vacuum and aqueous solution conditions were studied by density functional theory (DFT). The results show that tinidazole can adsorb on the surfaces of TiO(101) and (001) under different conditions. The hydrogen bond generated during the adsorption process can enhance the stability of the adsorption configuration, which makes the bond length of C-N of tinidazole longer and finally facilitates the ring-opening degradation reaction.
View Article and Find Full Text PDFIn order to investigate the adsorption behaviors of sulfonamides onto hydroxylated multi - walled carbon nanotubes (CNTs) with a porous structure and large specific surface area, six typical sulfonamides including sulfanilamide (SAM), sulfamerazine (SMR), sulfadimethoxine (SMX), sulfadiazine (SDZ), sulfamethazine (SMT) and sulfametoxydiazine (SMD) were selected to be adsorbed respectively on CNTs, and in the same time the structural parameters of the six sulfonamides molecules were calculated according to the density functional theory (DFT). Based upon above mentioned experiments and the structural parameters, the quantitative correlation between the structural parameters of sulfonamides molecules and their adsorption affinity (e.g.
View Article and Find Full Text PDFIn this paper, density functional theory (DFT) was performed to study the adsorption properties of ornidazole on anatase TiO(101) and (001) crystal facets under vacuum, neutral and acid-base conditions. We calculated the adsorption structure of ornidaozle on the anatase TiO surface, optimal adsorption sites, adsorption energy, density of states, electronic density and Milliken atomic charge under different conditions. The results show that when the N(3) atom on the imidazole ring is adsorbed on the Ti(5) atom, the largest adsorption energy and the most stable adsorption configuration could be achieved.
View Article and Find Full Text PDFThere is a need to develop highly efficient materials for capturing uranium from nuclear wastewater. Here, 5-methylbenzotriazole modified graphene oxide (MBTA-GO) was used to adsorb U(VI) from aqueous solution. By the trials of different conditions, we found that the removal of U(VI) from acidic solution was strongly dependent on pH but independent of ionic strength.
View Article and Find Full Text PDFThe adsorption characteristics of metronidazole on anatase TiO(101) and (001) surfaces were studied by density functional theory (DFT). The adsorption structure of metronidazole on anatase TiO(101) and (001) surfaces has been optimized under vacuum, water, acidic, and alkaline conditions, respectively. The optimum adsorption site, adsorption energy, and electronic structure of the stable adsorption model were calculated.
View Article and Find Full Text PDFRNA polymerase (RNAP) is the primary machine responsible for transcription. Its ability to distinguish between correct (cognate) and incorrect (noncognate) nucleoside triphosphates (NTPs) is important for fidelity control in transcription. In this work, we investigated the substrate selection mechanism of T7 RNAP from the perspective of energetics.
View Article and Find Full Text PDFThe adsorption of 20 amino acids (AAs) on the (101) surface of anatase titanium dioxide (TiO) has been investigated under the scheme of density functional theory. Through the analysis of adsorption geometries, amino group and side chains of AAs have been identified as the major side to adsorb on TiO, while the carboxyl group prefers to stay outside to avoid the repulsion between negatively charged oxygen from TiO and AAs. On the surface, two-coordinated oxygen is the major site to stabilize AAs through O-H interactions.
View Article and Find Full Text PDFThe catalytic coupling reaction mechanism of the transformation from 4-nitrobenzenethiol (4-NBT) to 4,4'-dimercaptoazobenzene (4,4'-DMAB) on a silver cluster was studied by density functional theory. Reactants, intermediates, transition states and products were optimized with the B3LYP method using the 6-311 + G(d,p) basis set (Ag using the pseudo potential basis set of LanL2DZ). Transition states and intermediates were confirmed by the corresponding vibration analysis and intrinsic reaction coordinates (IRC).
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