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Showing 1 to 20 of 46 for “"time-dependent density functional theory"”.
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Orbital Functionals in Time-Dependent Density-Functional Theory
The subject of this work are orbital functionals in density-functional theory (DFT). After a short introduction the basic ideas of static and time-dependent DFT are presented in Chap. 2. In this chapter the advantages and disadvantages of common approximations for the exchange-correlation (xc) …
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Correlated electron dynamics and memory in time-dependent density functional theory
Korrelierte Elektronendynamik ist für nichtlineare und lineare Prozesse in Atomen und Molekülen von großer Bedeutung. Dies betrifft insbesondere die Wechselwirkung mit starken Feldern und die Photoabsorptionsspektren. Die theoretische Beschreibung der Korrelationen gestaltet sich jedoch im …
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Charge and excitation-energy transfer in time-dependent density functional theory
… is of practical relevance. In principle, density functional theory (DFT) and time-dependent density functional theory (TDDFT) appear as natural choices to study the relevant sizable molecules on a first-principles scale at bearable computational cost. However, the application of standard …
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Exchange-Correlation Kernels Within Time-Dependent Density Functional Theory For Ground-State and Excited-State Properties
The exact exchange-correlation kernel is a functional derivative of the exact time-dependent exchange-correlation (XC) potential with respect to the time-dependent density, evaluated at the ground-state density. As the XC potential is not known, the exact kernel is also unavailable. Therefore, it …
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Excited State Dynamics of Trans-Cis Photoisomerization in Photoactive Yellow Protein Chromophores
… and condensed phase applications, pseudospectral time-dependent density functional theory (PS-TDDFT) is presented, which alleviates the O(N4) scaling problem in two-electron integral calculations. For the test cases in this work, PS-TDDFT is up to 10 times faster than the conventional TDDFT with …
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A Time-Resolved Fluorescence Study of Silicon Nanoparticles: Testing the Dimer Stretching Model
… to a fully reconstructed structure using time dependent density functional theory. Despite the inclusion of a fully reconstructed structure and improved computational techniques, their simple stretching model produces an energy barrier inconsistent with the observed temperature-lifetime …
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Quantum Plasmonics: A first-principles investigation of metallic nanostructures and their optical properties
… first principles. An efficient implementation of time-dependent density functional theory allows a fully quantum mechanical description of systems large enough to display collective electron oscillations and surface plasmon modes. The results are compared with traditional classical …
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The Electronic Excited States of Green Fluorescent Protein Chromophore Models
… complete active space SCF (CASSCF) methods, time dependent density functional theory (TDDFT), equation-of motion coupled cluster (EOM-CCSD) and multireference perturbation theory (MRPT). Amongst the low-lying states we identify the optically bright pipi* state of the molecules and examine its …
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Tuning the photophysical properties of amidophosphine complexes of copper
… properties is reported. Luminescence lifetimes up to 150 [mu]s are observed in benzene solution at ambient temperature, which are comparable to the lifetimes of the longest-lived previously reported copper luminophores. These complexes also exhibit quantum yields up to 0 = 0.70 at 298 K. …
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Charge transport, configuration interaction and Rydberg states under density functional theory
Density functional theory (DFT) is a computationally efficient formalism for studying electronic structure and dynamics. In this work, we develop DFT-based excited-state methods to study electron transport, Rydberg excited states and to characterize diabatic electronic configurations and couplings. …
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Synthesis, structure and spectroscopic investigations of luminescent heterobimetallic gold(I)-Rhodium(I) species
… emission spectra, and phosphorescence lifetimes of glass-solution and solid state samples at 77 K are reported for 2-5 and interpreted in context of crystallographic structure, electronic structure, and time-dependent density functional theory (TD-DFT) calculations. 2-5 are intensely …
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Probing the dynamical response of organic molecules to intense laser pulses
… in which the electrons are described using time dependent density functional theory while the ions move classically. We begin by laying out the theory behind the work including an explanation of the calculations. Then we look at the interaction of benzene with both circularly- and …
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Synthesis and Computational Studies of a New Class of Lanthanide Niobate Cluster : [Ln<sub>4</sub>(H<sub>2</sub>O)<sub>8</sub>(SO<sub>4</sub>)<sub>5</sub>(NbO<sub>3</sub>)<sub>2</sub>]+3H<sub>2</sub>O; Ln= Dy, Tb
… were determined by crystallography and time-dependent density functional theory (TD-DFT) was used to provide insight into photo-induced electronic transitions. Supporting computational methods that are currently being developed for modeling these emerging cluster systems are …
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Composition, thermodynamics, and morphology: A multi-scale computational approach for the design of self-assembling peptides
… morphology and free energy of oligomerization, time dependent density functional theory to predict photophysical properties as a function of aggregate morphology, and data-driven quantitative structure property models to perform high-throughput virtual screening of chemical space to identify …
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Tddft Derivative Couplings And Other Topics In Quantum Chemistry
… interaction using the electronic structure theory. Two approaches are developed calculating the derivative couplings between the excited states within the time-dependent density functional theory. The behavior of the derivative couplings around a conical intersection is analyzed for two real …
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Ab-initio molecular dynamics studies of laser- and collision-induced processes in multielectron diatomics, organic molecules and fullerenes
… be treated classically and the electrons with time-dependent density functional theory (TD-DFT) in basis expansion. Depending on the actual system and physical process, well suited basis sets for the Kohn-Sham orbitals has to be chosen. For the ionization process a novel absorber acting in the …
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Real time density functional simulations of quantum scale conductance
… by subjecting a molecular junction to a time dependent potential and propagating the electronic state in real time using time-dependent density functional theory (TDDFT). This is in contrast with the more common steady-state nonequilibrium Green's function (NEGF) method. We start by …
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Structure, electronic levels, and ionic interactions of 1 nanometer silicon particles
… the excited state potential energy surface using time dependent density functional theory, which show radiative traps accessible via direct excitation at the band edge of the ground state geometry. The self-trapped excitons proposed by Lannoo et al. [1, 2] are found to be unstable for the Si29H24 …
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Development of non-born-Oppenheimer methods for ground and excited state molecular properties
… states, the linear response multicomponent time-dependent density functional theory (TDDFT) is derived and implemented within the NEO framework. The results for nuclear vibrational excitations of interest corresponding to single or multiple protons calculated with NEO-TDDFT are accurate when …
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Computational study on controlling the optical properties of solar thermal fuels
… thermal fuel material that exhibits high energy density, high energy conversion efficiency, long energy storage lifetime, and can be produced at low cost. A recent proposal is a nanotemplate-photoisomer hybrid system, e.g. functionalized azobenzene, a well-known photoisomer molecule, attached to …
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