English
Related papers

Related papers: Time-Dependent Relativistic Two-Component Equation…

200 papers

Motivated by the very low diffusivity recently found in ab initio simulations of liquid water, we have studied its dependence with temperature, system size, and duration of the simulations. We use ab initio molecular dynamics (AIMD),…

Soft Condensed Matter · Physics 2009-11-10 M. V. Fernandez-Serra , Emilio Artacho

An appropriate model Hamiltonian based formalism is proposed for a random adsorbate layer with arbitrary coverage and the ensuing two-dimensional band formation by metallic adsorbates in the monolayer regime. The coherent potential…

Chemical Physics · Physics 2007-05-23 A. K. Mishra

We develop methods to learn the correlation potential for a time-dependent Kohn-Sham (TDKS) system in one spatial dimension. We start from a low-dimensional two-electron system for which we can numerically solve the time-dependent…

Machine Learning · Statistics 2022-12-08 Harish S. Bhat , Kevin Collins , Prachi Gupta , Christine M. Isborn

We investigate the numerical accuracy of the extended Koopmans's theorem (EKT) in reproducing the full configuration interaction (FCI) and complete active-space configuration interaction (CAS-CI) ionization energies (IEs) of atomic and…

Chemical Physics · Physics 2024-06-28 Reza Hemmati , Mohammad Mostafanejad , J. V. Ortiz

During the last two decades density functional based linear response approaches have become the de facto standard for the calculation of optical properties of small and medium-sized molecules. At the heart of these methods is the solution…

Chemical Physics · Physics 2015-01-23 Robert Rüger , Erik van Lenthe , You Lu , Johannes Frenzel , Thomas Heine , Lucas Visscher

The electronic structure of atomic quantum systems and their dynamical interaction with light is reflected in transition dipole matrix elements coupling the system's energy eigenstates. In this work, we measure phase shifts of the…

The time-dependent optical properties of molecular systems are investigated by step-scan Fourier-transform spectroscopy in order to explore the dynamics at phase transitions and molecular orientation in the milli- and microsecond range. The…

Materials Science · Physics 2016-07-20 Tobias Peterseim , Martin Dressel

We consider the calculations of photoionization spectra and core resonances of open-shell systems using range-separated time-dependent density-functional theory. Specifically, we use the time-dependent range-separated hybrid (TDRSH) scheme,…

Chemical Physics · Physics 2023-01-11 Julien Toulouse , Karno Schwinn , Felipe Zapata , Antoine Levitt , Eric Cancès , Eleonora Luppi

We investigate the process of photon absorption by atoms or molecules shortly interacting with a laser beam in the dipole approximation. Assuming that the interaction time $\tau$ is much smaller than the lifetime of the corresponding…

We present accurate optical spectra of semiconductors and insulators within a pure Kohn-Sham time-dependent density-functional approach. In particular, we show that the onset of the absorption is well reproduced when comparing to…

Materials Science · Physics 2020-03-18 Sarah Cavo , J. A. Berger , Pina Romaniello

The problem of orbital relaxation in computational core-hole spectroscopies, including x-ray absorption and x-ray photoionization, has long plagued linear response approaches, including equation-of-motion coupled cluster with singles and…

Chemical Physics · Physics 2025-03-26 Megan E. Simons , Devin A. Matthews

Favorably scaling numerical time-dependent many-electron techniques such as time-dependent density functional theory (TDDFT) with adiabatic exchange-correlation potentials typically fail in capturing highly correlated electron dynamics. We…

Atomic Physics · Physics 2013-11-25 M. Brics , D. Bauer

Recent advances in laser technology enable to follow electronic motion at its natural time-scale with ultrafast pulses, leading the way towards atto- and femtosecond spectroscopic experiments of unprecedented resolution. Understanding of…

Chemical Physics · Physics 2023-07-12 Marius Kadek , Lukas Konecny , Michal Repisky

The electron attachment variant of equation-of-motion coupled-cluster theory (EOM-EA-CC) is generalized to the case of strong light-matter coupling within the framework of cavity quantum electrodynamics (QED). The resulting EOM-EA-QED-CC…

Chemical Physics · Physics 2022-02-23 Marcus D. Liebenthal , Nam Vu , A. Eugene DePrince

Time-dependent quantum chemical methods coupled to Gaussian basis sets are gaining popularity in modeling the electron dynamics of atoms and molecules interacting with intense laser fields. Two approaches most widely used for this purpose,…

Chemical Physics · Physics 2023-01-18 Aleksander P. Woźniak , Maciej Lewenstein , Robert Moszyński

We present three schemes to go beyond the electric-dipole approximation in X-ray absorption spectroscopy calculations within a four-component relativistic framework. The first is based on the full semi-classical light-matter interaction…

Chemical Physics · Physics 2021-07-02 Nanna Holmgaard List , Timothé Romain Léo Melin , Martin van Horn , Trond Saue

In this first of three articles on the optical absorption of electrons in half-filled Peierls-distorted chains we present analytical results for non-interacting tight-binding electrons. We carefully derive explicit expressions for the…

Condensed Matter · Physics 2015-06-25 F. Gebhard , K. Bott , M. Scheidler , P. Thomas , S. W. Koch

Spectral properties of the Hamiltonian function which characterizes a trapped ion are investigated. In order to study semiclassical dynamics of trapped ions, coherent state orbits are introduced as sub-manifolds of the quantum state space,…

Quantum Physics · Physics 2023-02-28 Bogdan M. Mihalcea

Real-time simulations of laser-driven electron dynamics contain information about molecular optical properties through all orders in response theory. These properties can be extracted by assuming convergence of the power series expansion of…

We introduce real-time density matrix embedding theory (DMET), a dynamical quantum embedding theory for computing non-equilibrium electron dynamics in strongly correlated systems. As in the previously developed static DMET, real-time DMET…

Chemical Physics · Physics 2017-11-03 Joshua S. Kretchmer , Garnet Kin-Lic Chan