A highly efficient new algorithm for time-dependent density-functional theory (TDDFT) calculations is presented. In this algorithm, a dual-level approach to speed up DFT calculations (Nakajima and Hirao, J Chem Phys 2006, 124, 184108) is combined with a state-specific (SS) algorithm for TDDFT (Chiba et al., Chem Phys Lett 2006, 420, 391). The dual-level SS-TDDFT algorithm was applied to excitation energy calculations of typical small molecules, the Q bands of the chlorophyll A molecule, the charge-transfer energy of the zincbacteriochlorin-bacteriochlorin model system, and the lowest-lying excitation of the circumcoronene molecule. As a result, it was found that the dual-level SS-TDDFT gave correct excitation energies with errors of 0.2-0.3 eV from the standard TDDFT approach, with much lower CPU times for various types of excitation energies of large-scale molecules.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/jcc.20871 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Excited state properties from the Bethe-Salpeter equation: State-to-state transitions and spin-orbit coupling.
J Chem Phys
December 2024
Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, Kaiserstraße 12, 76131 Karlsruhe, Germany.
The formalism to calculate excited state properties from the GW-Bethe-Salpeter equation (BSE) method is introduced, providing convenient access to excited state absorption, excited state circular dichroism, and excited state optical rotation in the framework of the GW-BSE method. This is achieved using the second-order transition density, which can be obtained by solving a set of auxiliary equations similar to time-dependent density functional theory (TD-DFT). The proposed formulation therefore leads to no increase in the formal computational complexity when compared to the corresponding ground state properties.
View Article and Find Full Text PDFICT-based fluorescent nanoparticles for selective cyanide ion detection and quantification in apple seeds.
Analyst
December 2024
Department of Chemistry, Khalifa University of Science and Technology, Abu Dhabi, P.O. Box 127788, United Arab Emirates.
In this report, we successfully engineered a novel probe based on an acceptor-donor-acceptor (A-D-A) architecture featuring dicyanovinyl-substituted thieno[3,2-]thiophene, termed DCVTT. The designed probe self-assembles into luminous nanoparticles (DCVTT NPs) upon introducing mixed aqueous solutions. These fluorescent nanostructures served as a ratiometric probe for detecting cyanide (CN) ions in aqueous-based environments, owing to the robust Intramolecular Charge Transfer (ICT) characteristics of DCVTT.
View Article and Find Full Text PDFA TDDFT exploration on the excited-state intramolecular proton transfer in 2-(2'-hydroxyphenyl)-benzimidazole derivatives.
Spectrochim Acta A Mol Biomol Spectrosc
December 2024
Zhejiang Sci-Tech University, Hangzhou 310018, China. Electronic address:
Excited-state intramolecular proton transfer (ESIPT) reactions are one of the fundamental energy transformation reactions in catalysis and biological process. The combining ESIPT with the twisted intramolecular charge transfer (TICT) brings the richness of optical, photoelectronic performances to certain functional compounds. Delineating the mechanism of ESIPT + TICT reactions and further understanding why a specific functional group dominates are fundamentally crucial for the design and application of the functionally photoelectric materials.
View Article and Find Full Text PDFSynthesis and Excited State Proton Transfer (ESPT) Studies of 2-(6-Substitutedbenzo[d]Thiazol-2-Yl)Naphthalen-1-Ol Derivatives.
J Fluoresc
December 2024
Department of Chemistry, Sant Longowal Institute of Engineering & Technology, Longowal (Sangrur), Punjab, 148106, India.
This study reports the rapid intramolecular proton transfer studies upon photo excitation of 2-(benzo[d]thiazol-2-yl)naphthalene-1-ol derivatives, yielding tautomer emission with large Stokes shift. Employing photophysical studies, density functional theory (DFT) and, time-dependent density functional theory (TD-DFT) methods, we scrutinize excited state intramolecular proton transfer (ESIPT) modulation over varying solvent polarities. Analysis of UV-Visible and fluorescence spectra, alongside exploration of hydrogen bond dynamics, reveals solvation effects on the excited state proton transfer process.
View Article and Find Full Text PDFGlobin ferryl species: what is the nature of the protonation event at pH < 5?
J Biol Inorg Chem
December 2024
Department of Chemistry, Babes-Bolyai University, 11 Arany Janos Str., 400028, Cluj-Napoca, Romania.
The ferryl state in globins has previously been reported to undergo a protonation event below pH 5, as assessed using pH jump experiments with stopped-flow UV-Vis spectroscopy. This protonation entails hypsochromic shifts in the α and β bands (~ 20 to 40 nm) and an ~ 10 nm reduction in the energy difference between these two bands. We now report that in Mb this event is also characterized by a hypsochromic shift in the Soret band (~ 5 nm).
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!