Article
Chemistry, Physical
Jared R. Williams, Nicolas Tancogne-Dejean, Carsten A. Ullrich
Summary: Time-dependent density-functional theory (TDDFT) is an efficient method for calculating optical spectra, providing insight into exciton dynamics by obtaining exciton wave functions and understanding the formation and dissociation of excitons in real time.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2021)
Article
Physics, Multidisciplinary
Shuai Qin, Cong-Zhang Gao, Wandong Yu, Yi-Zhi Qu
Summary: The study calculated the multi-electron capture and loss cross-sections of Ar+-Ne collisions in the few-keV/a.u. regime using an inverse collision framework, time-dependent density functional theory, and molecular dynamics. The extraction of capture and loss probabilities was based on the particle-number projection technique, with good agreement found between experimental and theoretical data. The non-negligible post-collision decay of the projectile's electrons further supported the applicability of the approach to complex many-electron collision systems.
CHINESE PHYSICS LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Cody Covington, Justin Malave, Kalman Varga
Summary: Coupled Maxwell and time-dependent orbital-free calculations are used to study the interaction of electromagnetic waves and matter, showing good agreement with time-dependent density functional calculations for various systems.
Article
Physics, Condensed Matter
John McFarland, Efstratios Manousakis
Summary: Imaginary-time time-dependent density functional theory (it-TDDFT) is proposed as an alternative method for obtaining the ground state within density functional theory, avoiding convergence difficulties encountered by the self-consistent-field iterative method. By modifying the Quantum ESPRESSO package, it-TDDFT propagation for periodic systems has been successfully implemented, demonstrating accurate results for different calculations using ultra-soft or norm-conserving pseudo potentials.
JOURNAL OF PHYSICS-CONDENSED MATTER
(2021)
Article
Engineering, Environmental
Sharma S. R. K. C. Yamijala, Ravindra Shinde, Kota Hanasaki, Zulfikhar A. Ali, Bryan M. Wong
Summary: PFASs are hazardous contaminants found in drinking water sources, and recent experimental efforts have focused on photo-induced processes to accelerate their degradation. This study provides crucial insights into the mechanism of photo-induced degradation of PFASs using RT-TDDFT calculations, showing that photo-induced excitations can be highly selective in dissociating the C-F bond.
JOURNAL OF HAZARDOUS MATERIALS
(2022)
Review
Chemistry, Physical
Neepa T. Maitra
Summary: Time-dependent density functional theory is a preferred method for calculating spectra and response properties in physics, chemistry, and biology. Its ability to scale to larger systems has made computations possible that were not previously achievable. While simple functional approximations have been successful in handling increasingly complex and interesting systems, there is a growing awareness that these approximations may fail for certain classes of problems. This review discusses the challenges and progress in describing double excitations and charge-transfer excitations, two common obstacles to the theory's application.
ANNUAL REVIEW OF PHYSICAL CHEMISTRY
(2022)
Article
Physics, Multidisciplinary
Hui-Hui Zhang, Wan-Dong Yu, Cong-Zhang Gao, Yi-Zhi Qu
Summary: We investigate the charge transfer of a Li2+ + Ar collision system using the time-dependent density functional theory non-adiabatically coupled to molecular dynamics. By employing the particle number projection method, we extract the single- and double-charge transfer cross sections at MeV energies, which are in good agreement with experimental data. The analysis of charge transfer probabilities reveals that single-charge transfer occurs over a wider range of impact parameters for energies higher than 1.0 MeV, while double-charge transfer is dominated by close collisions. Furthermore, we compute the orbital projection probabilities to determine the population of captured electrons, and find that the electrons of Ar are most likely to transfer to the 2p orbitals of Li2+, with only a small fraction captured in the s orbitals. This study demonstrates the capability of the proposed methodology in dealing with charge transfer in dressed ion collisions at MeV energies.
CHINESE PHYSICS LETTERS
(2023)
Article
Chemistry, Physical
Giulia Giannone, Szymon Smiga, Stefania D'Agostino, Eduardo Fabiano, Fabio Della Sala
Summary: In plasmonics, theoretical analysis of the coupling between metallic nanoparticles or between an emitter and metallic nanoparticles is crucial for designing new systems. Time-dependent density functional theory (TD-DFT) considers quantum and spill-out effects, but the subsystem formulation of TD-DFT allows for direct computation of plasmon couplings and analysis of charge-transfer effects. This approach can reproduce reference calculations and is useful for both gap distances greater than 6 angstrom and hybrid plasmonic systems.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Automation & Control Systems
Sobhi Barg, Kent Bertilsson
Summary: This article proposes a novel approach to understand the different kinds of core loss in the trapezoidal flux waveform. The study shows that the total loss is composed of two terms, and two models with accuracy higher than 96% are developed to predict the relaxation loss. The models are verified with experimental results.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2021)
Article
Chemistry, Multidisciplinary
Matteo De Santis, Valerie Vallet, Andre Severo Pereira Gomes
Summary: In this work, the performance of real-time time-dependent block-orthogonalized Manby-Miller embedding (rt-BOMME) approach is investigated in reproducing X-ray absorption spectra (XAS) obtained with standard real-time frozen density embedding time-dependent density functional theory (rt-TDDFT-in-DFT FDE) simulations. Model systems of solvated fluoride and chloride ions ([X@ ( H2O)(8)](-) , X = F, Cl) are considered. The results show that the BOMME approach provides significantly better agreement with supermolecular results in ground-state quantities compared to FDE for the strongly interacting fluoride system, while for chloride the two methods show similar results. For excited states, the BOMME approach provides a faithful qualitative representation of the spectra in all energy regions considered, but it induces non-negligible shifts in peak positions for the excitations from the halide to the environment due to its lower-accuracy exchange-correlation functional. The study concludes that QM/QM embedding approaches are viable alternatives for real-time simulations of X-ray absorption spectra of species in complex or confined environments.
FRONTIERS IN CHEMISTRY
(2022)
Article
Physics, Multidisciplinary
Jiuyu Sun, Cheng-Wei Lee, Alina Kononov, Andre Schleife, Carsten A. Ullrich
Summary: Linear-response time-dependent density-functional theory (TDDFT) can accurately describe excitonic features in the optical spectra of insulators and semiconductors. By utilizing real-time TDDFT, it is possible to model excitons and study femtosecond exciton dynamics following short-pulse excitations, with potential extensions into the nonlinear regime.
PHYSICAL REVIEW LETTERS
(2021)
Article
Materials Science, Multidisciplinary
Tetsuro Habe, Koichi Nakamura
Summary: The research reveals the presence of excitons in the monolayer crystal and evaluates its optical property using numerical methods. Additionally, it confirms the consistency of the optical property of the bulk crystal with previous experimental results, independent of the number of layers.
Article
Biochemistry & Molecular Biology
Austin Biaggne, William B. Knowlton, Bernard Yurke, Jeunghoon Lee, Lan Li
Summary: The properties of dye monomers greatly influence their aggregation ability and exciton dynamics. By engineering dyes with specific substituents, optimal key properties like hydrophobicity and dipole moments can be achieved. This study found that electron withdrawing substituents significantly affect the solvation energy of the dye, while various pairs of substituents can enhance the static dipole difference.
Article
Chemistry, Multidisciplinary
Marco Medves, Giovanna Fronzoni, Mauro Stener
Summary: This article presents a new set of auxiliary basis functions suitable for fitting the induced electron density. The set has been optimized to accurately calculate absorption spectra using the complex polarizability algorithm of time-dependent density functional theory (TDDFT). An automatic procedure has been developed to evaluate the resemblance of the calculated spectra to a reference, allowing for the reduction of the basis set size while maximizing accuracy. This new set of basis functions has already been included in the latest release of the AMS suite of programs, and will greatly improve the applicability range of the polTDDFT method with higher accuracy and less computational effort.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2022)
Article
Chemistry, Physical
Woojin Park, Marc Alias-Rodriguez, Daeheum Cho, Seunghoon Lee, Miquel Huix-Rotllant, Cheol Ho Choi
Summary: It is demonstrated that the mixed-reference spin-flip-time-dependent density functional theory (MRSF-TDDFT) can readily achieve the challenging core-hole particle orbital relaxation for core electron spectra, providing high accuracy and practicality.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Correction
Chemistry, Physical
Alejandro Rivero Santamaria, Maite Alducin, Ricardo Diez Muino, J. Inaki Juaristi
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Chemistry, Multidisciplinary
Antton Babaze, Ruben Esteban, Andrei G. Borisov, Javier Aizpurua
Summary: The optical response of a system composed of a quantum emitter and a plasmonic gap nanoantenna was theoretically studied using classical electrodynamics and TDDFT. It was found that the hybridization between electronic states strongly modifies the optical resonances of the coupled system, emphasizing the importance of correctly addressing electronic coupling processes.
Article
Chemistry, Physical
M. J. Ambrosio, E. Plesiat, P. Decleva, P. M. Echenique, R. Diez Muino, F. Martin
Summary: In this study, we examine the photoemission cross sections and Wigner time delays from MoS2 core-level orbitals. We analyze the scattering effects by neighboring atoms using a cluster approach and progressively larger model clusters. The results show that the Wigner-time-delay scale increases with larger clusters, indicating the presence of high order scattering processes and interference. Furthermore, internal propagation pathways start taking shape for the largest clusters.
Article
Chemistry, Physical
Francois Aguillon, Dana Codruta Marinica, Andrei G. Borisov
Summary: The study reveals that even a defect fraction as low as 10(-3) of the total number of carbon atoms in ideal graphene nanoflakes leads to significant broadening of the plasmon resonance in the optical absorption spectrum. In addition to effects from defect-induced scattering and modification of graphene's electronic structure, the study also observes and explains vacancy and impurity-induced shifts of the plasmon energy.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Physics, Multidisciplinary
Anna Roslawska, Tomas Neuman, Benjamin Doppagne, Andrei G. Borisov, Michelangelo Romeo, Fabrice Scheurer, Javier Aizpurua, Guillaume Schull
Summary: Experimental and theoretical investigation of the interactions between excited states of a single chromophore and static and dynamic electric fields varying at the atomic scale. The fluorescence maps of the chromophore with intramolecular resolution reveal the static charge redistribution and dynamic charge oscillation associated with the molecular exciton.
Article
Nanoscience & Nanotechnology
Fernando Aguilar-Galindo, Mario Zapata-Herrera, Sergio Diaz-Tendero, Javier Aizpurua, Andrei G. Borisov
Summary: This theoretical work explores the role of a NaCl ionic crystal spacer layer in decoupling an adsorbate from the substrate and changing the interplay between decay channels of an excited molecule. Quantitative assessment of decay rates helps establish the minimum thickness of the spacer required for observing molecular luminescence.
Article
Optics
Antton Babaze, Eduardo Ogando, P. Elli Stamatopoulou, Christos Tserkezis, N. Asger Mortensen, Javier Aizpurua, Andrei G. Borisov, Ruben Esteban
Summary: In this study, time-dependent density functional theory (TDDFT) was used to investigate the impact of quantum-mechanical effects on the self-interaction Green's function, which governs the electromagnetic interaction between quantum emitters and plasmonic metallic nanoantennas. The results reveal that quantum effects, such as surface-enabled Landau damping and the spill out of induced charges, strongly influence the nanoantenna-emitter interaction, leading to a redshift and broadening of plasmonic resonances. These effects are not considered in classical theories that assume a local dielectric response of the metals.
Correction
Nanoscience & Nanotechnology
Antton Babaze, Ruben Esteban, Javier Aizpurua, Andrei G. Borisov
Article
Chemistry, Physical
A. Rodriguez-Fernandez, L. Bonnet, P. Larregaray, R. Diez Muino
Summary: Hydrogen dissociation on clean W(110) surfaces is inhibited by the precoverage of oxygen on the tungsten surface. Density functional theory and ab initio molecular dynamics are used to explain the influence of adsorbed O atoms on the H2 dissociation process at the atomic scale. The adsorbed O atoms act as repulsive centers, closing dissociation pathways and preventing the further approach and dissociation of H2 molecules.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Francois Aguillon, Andrei G. Borisov
Summary: In this work, the impact of atomic scale lattice imperfections on the nonlinear response of graphene nanoflakes enhanced by resonance between electromagnetic fields and localized plasmon is investigated theoretically. Using the many-body time-dependent density matrix approach, it is found that a single defect in nanoflakes with thousands of carbon atoms can significantly affect the nonlinear hyperpolarizability and override symmetry constraints. This effect cannot be captured by the relaxation time approximation in quantum or classical frameworks. The results of this study have important implications for the design of nonlinear graphene devices.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Nanoscience & Nanotechnology
Antton Babaze, Tomas Neuman, Ruben Esteban, Javier Aizpurua, Andrei G. Borisov
Summary: The surface-response formalism (SRF) incorporates quantum surface-response corrections into classical electromagnetic theory via Feibelman parameters, providing a way to study quantum effects in the optical response of metallic nanostructures. However, the current method neglects the nonlocality of the optical response parallel to the metal-dielectric interface, which limits its applicability to systems with extreme field confinement. To address this limitation, a dispersive SRF based on a generalized Feibelman parameter is introduced, which correctly describes the plasmonic response of planar and nonplanar systems with extreme field confinement. This work significantly extends the applicability range of the SRF and contributes to the development of computationally efficient semiclassical descriptions of light-matter interaction that capture quantum effects.
Article
Chemistry, Physical
Natalia E. Koval, Daniel Sanchez-Portal, Andrei G. Borisov, Ricardo Diez Muino
Summary: In this work, the electronic friction problem of a negative point charge colliding with spherical jellium metal clusters is studied using real-time time-dependent density functional theory. The non-adiabatic, parameter-free results obtained serve as a benchmark for the widely used LDFA approximation and facilitate the discussion of various processes relevant to the electronic response of the system in the presence of the projectile.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Materials Science, Multidisciplinary
M. J. Ambrosio, E. Plesiat, P. Decleva, P. M. Echenique, R. Diez Muino, F. Martin
Summary: Methods of attosecond science, initially developed for gas phase systems, are now being adapted to study the temporal dynamics of electron in condensed-matter systems. Recent streaking measurements on the WSe2 dichalcogenide have provided information on photoemission time delays. In this work, an atomistic description of the photoemission process in WSe2 is presented and angularly resolved photoemission cross sections and time delays from various core states are provided. The results highlight the importance of scattering effects for accurate descriptions of the photoemission process.
Article
Materials Science, Multidisciplinary
Francois Aguillon, Dana Codruta Marinica, Andrei G. Borisov
Summary: This study addresses the possibility of atomic-scale control of the plasmon modes in graphene nanostructures, showing that carbon atom vacancies can switch or change the frequency of the longitudinal plasmon modes. These findings provide a platform for optical response engineering or sensing in 2D materials.
