English
Related papers

Related papers: A complex Gaussian approach to molecular photoioni…

200 papers

We implement a full nonlinear optimization method to fit continuum states with complex Gaussians. The application to a set of regular scattering Coulomb functions allows us to validate the numerical feasibility, to explore the range of…

Computational Physics · Physics 2020-08-28 Abdallah Ammar , Arnaud Leclerc , Lorenzo Ugo Ancarani

The ionization by photon or electron impact of the inner (2a1) and outer (1t2) valence orbitals of the CH4 molecule is investigated theoretically. In spite of a number of approximations, including a monocentric approach and a rather simple…

Chemical Physics · Physics 2024-05-15 Abdallah Ammar , Arnaud Leclerc , Lorenzo Ugo Ancarani

We present a method to compute the photoionization spectra of atoms and molecules in linear response time-dependent density functional theory. The electronic orbital variations corresponding to ionized electrons are expanded on a basis set…

Computational Physics · Physics 2023-05-24 Ivan Duchemin , Antoine Levitt

Complex Gaussian basis sets are optimized to accurately represent continuum radial wavefunctions over the whole space. First, attention is put on the technical ability of the optimization method to get more flexible series of Gaussian…

Chemical Physics · Physics 2025-11-04 Stéphanie Laure Egome Nana , Arnaud Leclerc , Lorenzo Ugo Ancarani

In this work we present a new method of approximating the continuum wavefunctions with a discrete basis set. This method aims to be at least compatible with other well known methods of the electronic structure theory to describe processes…

Chemical Physics · Physics 2019-09-18 Mateusz S. Szczygieł , Michał Lesiuk , Robert Moszynski

New approach to highly accurate calculations of the photodetachment cross-sections of the negatively charged hydrogen ions is developed. This effective, fast and numerically stable method is based on the use of the Rayleigh's formula for…

Solar and Stellar Astrophysics · Physics 2015-09-09 Alexei M. Frolov

The calculation of partial two-photon ionization cross sections in the above-threshold energy region is discussed in the framework of exterior complex scaling. It is shown that with a minor modification of the usual procedure, which is…

Atomic Physics · Physics 2018-08-17 Andrej Mihelič

We present a theoretical method for calculating multiphoton ionization amplitudes and cross sections of few-electron atoms. The present approach is based on an extraction of partial wave amplitudes from a scattering wave function, which is…

Atomic Physics · Physics 2021-04-21 Andrej Mihelic , Martin Horvat

A precise understanding of mechanisms governing the dynamics of electrons in atoms and molecules subjected to intense laser fields has a key importance for the description of attosecond processes such as the high-harmonic generation and…

Multicentric integrals that involve a continuum state cannot be evaluated with the usual quantum chemistry tools and require a special treatment. We consider an initial molecular bound state described by multicenter spherical or cartesian…

Quantum Physics · Physics 2021-11-17 Abdallah Ammar , Arnaud Leclerc , Lorenzo Ugo Ancarani

We outline a non-perturbative procedure for calculating the total photoionization cross-section of two-electron atomic systems. The procedure is based on the Floquet-Fourie representation of the solution of the time-dependent Schrodinger…

Atomic Physics · Physics 2007-05-23 I. A. Ivanov , A. S. Kheifets

We calculate the photo-ionization cross-section from the ground state of the helium atom, using the complex rotation method and diagonalization of sparse matrices. This produces directly the positions and widths of the doubly excited 1Po…

chao-dyn · Physics 2009-10-31 Benoit Gremaud , Dominique Delande

Photoionization cross sections and rate coefficients have been calculated for all bound vibrational levels of the 1s$\sigma_{\mathrm{g}}$ state of H$_{2}^{+}$, HD$^{+}$, and D$_{2}^{+}$. The Born-Oppenheimer approximation is employed in our…

Atomic Physics · Physics 2023-11-03 Adam Singor , Liam H. Scarlett , Mark C. Zammit , Igor Bray , Dmitry V. Fursa

We describe a method for the calculation of photoionization cross-sections using square-integrable amplitudes obtained from the diagonalization of finite-basis set representations of the electronic Hamiltonian. Three examples are…

Atomic Physics · Physics 2017-02-01 Alex Kozlov , Saumitra Saha , Harry Quiney

A methodology is developed to compute photoionization cross-sections beyond the electric dipole (BED) approximation from response theory, using Gaussian type orbitals and plane waves for the initial and final states, respectively. The…

Atomic Physics · Physics 2019-02-20 Iulia Emilia Brumboiu , Olle Eriksson , Patrick Norman

The development of attosecond technology has enabled the real-time observation of coherent electron motion in atoms, molecules and condensed phases. Experimentally, it is now possible to generate laser pulses of durations of only a few tens…

Chemical Physics · Physics 2017-05-18 David Ayuso

We propose a continuous variable quantum state tomography protocol of electrons which result from the ionization of atoms or molecules by the absorption of extreme ultraviolet light pulses. Our protocol is benchmarked against a direct…

We develop semiclassical approximations for calculating photoabsorption cross sections beyond the continuum threshold in quantum many-body systems. These approximations use the fully quantum-mechanical Wigner function of the ground state…

Atomic Physics · Physics 2023-05-24 Julien Toulouse

A numerical integration method for guiding-center orbits of charged particles in toroidal fusion devices with three-dimensional field geometry is described. Here, high order interpolation of electromagnetic fields in space is replaced by a…

Plasma Physics · Physics 2020-12-11 M. Eder , C. G. Albert , L. M. P. Bauer , S. V. Kasilov , W. Kernbichler

A novel approach for calibrating quantum-chemical properties determined as part of a high-throughput virtual screen to experimental analogs is presented. Information on the molecular graph is extracted through the use of extended…

Chemical Physics · Physics 2015-10-05 Edward O. Pyzer-Knapp , Gregor N. Simm , Alan Aspuru-Guzik
‹ Prev 1 2 3 10 Next ›