99 citations · 308 across the 18 of their papers we have counts for
18 papers
Double-pair Coulomb and Breit photon correction to the correlated relativistic energy
Péter Jeszenszki, Edit Mátyus
The simplest, algebraic quantum-electrodynamical corrections, due to the double-negative energy subspace and instantaneous interactions, are computed to the no-pair energy of two-s…
High-Precision Quantum Dynamics of He over the b -c Electronic Subspace by including Non-adiabatic, Relativistic and QED Corrections and Couplings
Balázs Rácsai, Péter Jeszenszki, Ádám Margócsy +1
Relativistic, quantum electrodynamics, as well as non-adiabatic corrections and couplings, are computed for the b and c electronic states of the…
Spin-dependent terms of the Breit-Pauli Hamiltonian evaluated with an explicitly correlated Gaussian basis set for molecular computations
Péter Jeszenszki, Péter Hollósy, Ádám Margócsy +1
This work collects the spin-dependent leading-order relativistic and quantum-electrodynamical corrections for the electronic structure of atoms and molecules within the non-relativ…
Rovibrational computations for the He a state including non-adiabatic, relativistic, and QED corrections
Ádám Margócsy, Balázs Rácsai, Péter Jeszenszki +1
A potential energy curve (PEC) accurate to a fraction of 1 ppm () is computed for the state of He endowed with relativistic and QED corrections. The…
One-particle operator representation over two-particle basis sets for relativistic QED computations
Péter Hollósy, Péter Jeszenszki, Edit Mátyus
This work is concerned with two-spin-1/2-fermion relativistic quantum mechanics, and it is about the construction of one-particle projectors using an inherently two(many)-particle,…
Lower bounds on par with upper bounds for few-electron atomic energies
Miklos Ronto, Peter Jeszenszki, Edit Mátyus +1
The development of computational resources has made it possible to determine upper bounds for atomic and molecular energies with high precision. Yet, error bounds to the computed e…
Relativistic two-electron atomic and molecular energies using coupling and double groups: role of the triplet contributions to singlet states
Péter Jeszenszki, Edit Mátyus
The triplet contribution is computed to the 1 and 2 states of the He atom, to the state of the Li and Be ions, and to the $X\ ^1Σ_…
The Bethe-Salpeter QED wave equation for bound-state computations of atoms and molecules
Edit Mátyus, Dávid Ferenc, Péter Jeszenszki +1
Interactions in atomic and molecular systems are dominated by electromagnetic forces and the theoretical framework must be in the quantum regime. The physical theory for the combin…
Variational versus perturbative relativistic energies for small and light atomic and molecular systems
Dávid Ferenc, Péter Jeszenszki, Edit Mátyus
Variational and perturbative relativistic energies are computed and compared for two-electron atoms and molecules with low nuclear charge numbers. In general, good agreement of the…
On the Breit interaction in an explicitly correlated variational Dirac-Coulomb framework
Dávid Ferenc, Péter Jeszenszki, Edit Mátyus
The Breit interaction is implemented in the no-pair variational Dirac-Coulomb (DC) framework using an explicitly correlated Gaussian basis reported in the previous paper [Paper I:…
Variational Dirac-Coulomb explicitly correlated computations for atoms and molecules
Péter Jeszenszki, Dávid Ferenc, Edit Mátyus
The Dirac-Coulomb equation with positive-energy projection is solved using explicitly correlated Gaussian functions. The algorithm and computational procedure aims for a parts-per-…
On the inclusion of cusp effects in expectation values with explicitly correlated Gaussians
Péter Jeszenszki, Robbie T. Ireland, Dávid Ferenc +1
This paper elaborates the integral transformation technique of [K. Pachucki, W. Cencek, and J. Komasa, J. Chem. Phys. 122, 184101 (2005)] and uses it for the case of the non-relati…
All-order relativistic computations for atoms and molecules using an explicitly correlated Gaussian basis
Péter Jeszenszki, Dávid Ferenc, Edit Mátyus
A variational solution procedure is reported for the many-particle no-pair Dirac-Coulomb-Breit Hamiltonian aiming at a parts-per-billion (ppb) convergence of the atomic and molecul…
NECI: N-Electron Configuration Interaction with emphasis on state-of-the-art stochastic methods
Kai Guther, Robert J. Anderson, Nick S. Blunt +22
We present NECI, a state-of-the-art implementation of the Full Configuration Interaction Quantum Monte Carlo algorithm, a method based on a stochastic application of the Hamiltonia…
Eliminating the wave function singularity for ultracold atoms by similarity transformation
Péter Jeszenszki, Ulrich Ebling, Hongjun Luo +2
A hyperbolic singularity in the wave-function of -wave interacting atoms is the root problem for any accurate numerical simulation. Here we apply the transcorrelated method, whe…
Are smooth pseudopotentials a good choice for representing short-range interactions?
Péter Jeszenszki, Ali Alavi, Joachim Brand
When seeking a numerical representation of a quantum-mechanical multiparticle problem it is tempting to replace a singular short-range interaction by a smooth finite-range pseudopo…
Accelerating the convergence of exact diagonalization with the transcorrelated method: Quantum gas in one dimension with contact interactions
Péter Jeszenszki, Hongjun Luo, Ali Alavi +1
Exact diagonalization expansions of Bose or Fermi gases with contact interactions converge very slowly due to a non-analytic cusp in the wave function. Here we develop a transcorre…
The -wave scattering length of a Gaussian potential
Peter Jeszenszki, Alexander Yu. Cherny, Joachim Brand
We provide accurate expressions for the -wave scattering length for a Gaussian potential well in one, two and three spatial dimensions. The Gaussian potential is widely used as…