Browse
Submit Data
Databases
API
Help

Dataset Information

0 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

The Dependence of Implicit Solvent Model Parameters and Electronic Absorption Spectra and Photoinduced Charge Transfer.

ABSTRACT: In this work, the relationship between multiple solvent parameters and charge transfer index was analyzed by multi-factor multi-variate partial least squares regression (PLSR). The charge transfer of the molecule is visualized by the analysis of the excited state wave function. Hydrogen bond basicity and surface tension can significantly affect charge transfer by studying the solvation model parameters and charge transfer index. Finally, a method in which a solvent regulates charge transfer strength and migration length is proposed.

SUBMITTER: Chen X

PROVIDER: S-EPMC7048810 | biostudies-literature | 2020 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

The Dependence of Implicit Solvent Model Parameters and Electronic Absorption Spectra and Photoinduced Charge Transfer.

Chen Xiangtao X Qiao Wenhua W Miao Wenjing W Zhang Yangdong Y Mu Xijiao X Wang Jingang J

Scientific reports 20200228 1

In this work, the relationship between multiple solvent parameters and charge transfer index was analyzed by multi-factor multi-variate partial least squares regression (PLSR). The charge transfer of the molecule is visualized by the analysis of the excited state wave function. Hydrogen bond basicity and surface tension can significantly affect charge transfer by studying the solvation model parameters and charge transfer index. Finally, a method in which a solvent regulates charge transfer stre ...[more]

PMID: 32111955

Similar Datasets

Structure and electronic spectra of purine-methyl viologen charge transfer complexes.

Project description:The structure and properties of the electron donor-acceptor complexes formed between methyl viologen and purine nucleosides and nucleotides in water and the solid state have been investigated using a combination of experimental and theoretical methods. Solution studies were performed using UV-vis and (1)H NMR spectroscopy. Theoretical calculations were performed within the framework of density functional theory (DFT). Energy decomposition analysis indicates that dispersion and induction (charge-transfer) interactions dominate the total binding energy, whereas electrostatic interactions are largely repulsive. The appearance of charge transfer bands in the absorption spectra of the complexes are well-described by time-dependent DFT and are further explained in terms of the redox properties of purine monomers and solvation effects. Crystal structures are reported for complexes of methyl viologen with the purines 2'-deoxyguanosine 3'-monophosphate (DAD'DAD' type) and 7-deazaguanosine (DAD'ADAD' type). Comparison of the structures determined in the solid state and by theoretical methods in solution provides valuable insights into the nature of charge-transfer interactions involving purine bases as electron donors.

| S-EPMC3930082 | biostudies-literature

Fullerene-Based Photoactive Layers for Heterojunction Solar Cells: Structure, Absorption Spectra and Charge Transfer Process.

Project description:The electronic structure and optical absorption spectra of polymer APFO₃, [70]PCBM/APFO₃ and [60]PCBM/APFO₃, were studied with density functional theory (DFT), and the vertical excitation energies were calculated within the framework of the time-dependent DFT (TD-DFT). Visualized charge difference density analysis can be used to label the charge density redistribution for individual fullerene and fullerene/polymer complexes. The results of current work indicate that there is a difference between [60]PCBM and [70]PCBM, and a new charge transfer process is observed. Meanwhile, for the fullerene/polymer complex, all calculations of the twenty excited states were analyzed to reveal all possible charge transfer processes in depth. We also estimated the electronic coupling matrix, reorganization and Gibbs free energy to further calculate the rates of the charge transfer and the recombination. Our results give a clear picture of the structure, absorption spectra, charge transfer (CT) process and its influencing factors, and provide a theoretical guideline for designing further photoactive layers of solar cells.

| S-EPMC5455238 | biostudies-literature

Spectroscopic study of solvent effects on the electronic absorption spectra of flavone and 7-hydroxyflavone in neat and binary solvent mixtures.

Project description:The solvatochromic characteristics of flavone and 7-hydroxyflavone were investigated in neat and binary solvent mixtures. The spectral shifts of these solutes were correlated with the Kamlet and Taft parameters (?, ? and ?*) using linear solvation energy relationships. The multiparametric analysis indicates that both specific hydrogen bond donor ability and non-specific dipolar interactions of the solvents play an important role in absorption maxima of flavone in pure solvents. The hydrogen bond acceptor ability of the solvent was the main parameter affecting the absorption maxima of 7-hydroxyflavone. The simulated absorption spectra using a TD-DFT method were in good agreement with the experimental ones for both flavones. Index of preferential solvation was calculated as a function of solvent composition. Preferential solvation by ethanol was detected in cyclohexane-ethanol and acetonitrile-ethanol mixtures for flavone and in acetonitrile-ethanol mixtures for 7-hydroxyflavone. These results indicate that intermolecular hydrogen bonds between solute and solvent are responsible for the non-linear variation of the solvatochromic shifts on the mole fraction of ethanol in the analyzed binary mixtures.

| S-EPMC3257107 | biostudies-literature

Final-State Projection Method in Charge-Transfer Multiplet Calculations: An Analysis of Ti L-Edge Absorption Spectra.

Project description:A projection method to determine the final-state configuration character of all peaks in a charge transfer multiplet calculation of a 2p X-ray absorption spectrum is presented using a d(0) system as an example. The projection method is used to identify the most important influences on spectral shape and to map out the configuration weights. The spectral shape of a 2p X-ray absorption or L2,3-edge spectrum is largely determined by the ratio of the 2p core-hole interactions relative to the 2p3d atomic multiplet interaction. This leads to a nontrivial spectral assignment, which makes a detailed theoretical description of experimental spectra valuable for the analysis of bonding.

| S-EPMC4779055 | biostudies-literature

An implicit solvent model for SCC-DFTB with Charge-Dependent Radii.

Project description:Motivated by the need of rapidly exploring the potential energy surface of chemical reactions that involve highly charged species, we have developed an implicit solvent model for the approximate density functional theory, SCC-DFTB. The solvation free energy is calculated using the popular model that employs Poisson-Boltzmann for electrostatics and a surface-area term for non-polar contributions. To balance the treatment of species with different charge distributions, we make the atomic radii that define the dielectric boundary and solute cavity depend on the solute charge distribution. Specifically, the atomic radii are assumed to be linearly dependent on the Mulliken charges and solved self-consistently together with the solute electronic structure. Benchmark calculations indicate that the model leads to solvation free energies of comparable accuracy to the SM6 model (especially for ions), which requires much more expensive DFT calculations. With analytical first derivatives and favorable computational speed, the SCC-DFTB based solvation model can be effectively used, in conjunction with high-level QM calculations, to explore the mechanism of solution reactions. This is illustrated with a brief analysis of the hydrolysis of mono-methyl mono-phosphate ester (MMP) and tri-methyl mono-phosphate ester (TMP). Possible future improvements are also briefly discussed.

| S-EPMC2918909 | biostudies-literature

Modeling the Electronic Absorption Spectra of the Indocarbocyanine Cy3.

Project description:Accurate modeling of optical spectra requires careful treatment of the molecular structures and vibronic, environmental, and thermal contributions. The accuracy of the computational methods used to simulate absorption spectra is limited by their ability to account for all the factors that affect the spectral shapes and energetics. The ensemble-based approaches are widely used to model the absorption spectra of molecules in the condensed-phase, and their performance is system dependent. The Franck-Condon approach is suitable for simulating high resolution spectra of rigid systems, and its accuracy is limited mainly by the harmonic approximation. In this work, the absorption spectrum of the widely used cyanine Cy3 is simulated using the ensemble approach via classical and quantum sampling, as well as, the Franck-Condon approach. The factors limiting the ensemble approaches, including the sampling and force field effects, are tested, while the vertical and adiabatic harmonic approximations of the Franck-Condon approach are also systematically examined. Our results show that all the vertical methods, including the ensemble approach, are not suitable to model the absorption spectrum of Cy3, and recommend the adiabatic methods as suitable approaches for the modeling of spectra with strong vibronic contributions. We find that the thermal effects, the low frequency modes, and the simultaneous vibrational excitations have prominent contributions to the Cy3 spectrum. The inclusion of the solvent stabilizes the energetics significantly, while its negligible effect on the spectral shapes aligns well with the experimental observations.

| S-EPMC9268038 | biostudies-literature

Water-Triggered Photoinduced Electron Transfer in Acetonitrile-Water Binary Solvent. Solvent Microstructure-Tuned Reactivity of Hydrophobic Solutes.

Project description:The solvent-composition dependence of quenching triplet states of benzophenone (3BP) by anisole in acetonitrile-water (ACN-H2O) mixtures was investigated by laser flash photolysis over the water mole fraction (xw) increasing from 0 to 0.92. Single exponential decay of 3BP was observed over the whole composition range. The quenching rate constant consistently increased with the water content but increased far more rapidly with xw > 0.7. The water-triggered electron-transfer (ET) mechanism was confirmed by a steeply growing quantum yield of the benzophenone ketyl radical anion, escaping back-ET when the partial water volume exceeded the acetonitrile one. The water-content influence on the 3BP quenching rate was described by a kinetic model accounting for the microheterogeneous structure of the ACN-H2O mixtures and the very different solubility of the reactants in the solvent components. According to the model, the ET mechanism occurs at a rate constant of 1.46 × 109 M-1 s-1 and is presumably assisted by the ACN-H2O hydrogen-bonding interaction.

| S-EPMC7590979 | biostudies-literature

Physical Insight on Mechanism of Photoinduced Charge Transfer in Multipolar Photoactive Molecules.

Project description:Two series of novel dyes were designed based on the multipolar structures of the red dye D35 and blue dye DB, by introducing the furan (F), benzene ring (B) and benzo[c]thiophene (BT) groups into the conjugated bridge of D35 in proper order and adjusting the position of diketopyrrolopyrrole(DPP) unit and the incorporation of fluorine in the conjugated bridge of DB, respectively. We performed the quantum chemistry calculation to investigate the ground state and excited properties in a direct correlation with the spectra properties and abilities of losing or accepting electron for the original and designed molecules. Furthermore, the absorption spectra characteristics in consideration of the aggregation of dyes on the TiO2 layer and intermolecular charge transfer rate of the dimers were calculated. The obtained results indicate that the larger intermolecular charge transfer rate leads to the poor photoelectrical properties of the dyes, and the designed dyes D35-3 and DB-2 would exhibit the best photoelectrical properties among the investigated dyes due to their lower energy gaps, widened absorption spectra and prominent charge transfer properties.

| S-EPMC6031644 | biostudies-literature

Solvent-Dependent Characterization of Fucoxanthin through 2D Electronic Spectroscopy Reveals New Details on the Intramolecular Charge-Transfer State Dynamics.

Project description:The electronic state manifolds of carotenoids and their relaxation dynamics are the object of intense investigation because most of the subtle details regulating their photophysics are still unknown. In order to contribute to this quest, here, we present a solvent-dependent 2D Electronic Spectroscopy (2DES) characterization of fucoxanthin, a carbonyl carotenoid involved in the light-harvesting process of brown algae. The 2DES technique allows probing its ultrafast relaxation dynamics in the first 1000 fs after photoexcitation with a 10 fs time resolution. The obtained results help shed light on the dynamics of the first electronic state manifold and, in particular, on an intramolecular charge-transfer state (ICT), whose photophysical properties are particularly elusive given its (almost) dark nature.

| S-EPMC8279730 | biostudies-literature

Dynamic charge collecting mechanisms of cobalt phosphate on hematite photoanodes studied by photoinduced absorption spectroscopy.

Project description:Reaction sites, surface states, and surface loaded electrocatalysts are photoinduced charge storage sites and critical to photoelectrochemical (PEC) performance, however the charge transfer mechanisms involved in the three remain poorly understood. Herein, we studied the charge transfer processes in hematite (Fe2O3) without/with loaded cobalt phosphate (CoPi) by operando photoinduced absorption (PIA) spectroscopy. The loaded CoPi receives trapped holes in surface states at low potential and directly captures holes in the valence band at high potential. Through the dynamic hole storage mechanisms, loaded CoPi on Fe2O3 facilitates spatial charge separation and serves as a charge transfer mediator, instead of serving as a catalyst to change the water oxidation mechanism (constant third-order reaction). The spatial separation of photoinduced charges between Fe2O3 and CoPi results in more long-lived holes on the Fe2O3 surface to improve PEC water oxidation kinetically. The dynamic charge collecting mechanism sheds light on the understanding and designing of electrocatalyst loaded photoanodes.

| S-EPMC9930927 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

Tweets

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data