366 citations · 504 across the 19 of their papers we have counts for
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A Comparison of Relativistic Coupled Cluster and Equation of Motion Coupled Cluster Quadratic Response Theory
Xiang Yuan, Loïc Halbert, Lucas Visscher +1
We present the implementation of relativistic coupled cluster quadratic response theory (QR-CC), following our development of relativistic equation of motion coupled cluster quadra…
Relativistic Embedded Equation-of-Motion Coupled-Cluster Approach to the Core-Ionized States of Actinides: A Case Study of Uranyl(VI) in CsUOCl
Wilken Aldair Misael, Andre Severo Pereira Gomes
We investigate the core-level ionization energies of the bare uranyl ion (UO) and its interaction with X-rays when it is hosted in the CsUOCl crystalline envir…
Frequency-Dependent Quadratic Response Properties and Two-photon Absorption from Relativistic Equation-of-Motion Coupled Cluster Theory
Xiang Yuan, Loic Halbert, Lucas Visscher +1
We present the implementation of quadratic response theory based upon the relativistic equation-of-motion coupled cluster method. We showcase our implementation, whose generality a…
The performance of approximate equation of motion coupled cluster for valence and core states of heavy element systems
Loïc Halbert, Andre Severo Pereira Gomes
The equation of motion coupled cluster singles and doubles model (EOM-CCSD) is an accurate, black-box correlated electronic structure approach to investigate electronically excited…
Formulation and Implementation of Frequency-Dependent Linear Response Properties with Relativistic Coupled Cluster Theory for GPU-accelerated Computer Architectures
Xiang Yuan, Loic Halbert, Johann Pototschnig +4
We present the development and implementation of the relativistic coupled cluster linear response theory (CC-LR) which allows the determination of molecular properties arising from…
Core excitations of uranyl in CsUOCl from relativistic embedded damped-response time-dependent density functional theory calculations
Wilken Aldair Misael, André Severo Pereira Gomes
X-ray spectroscopies, by their high selectivity and sensitivity to the chemical environment around the atoms probed, provide significant insight into the electronic structure of mo…
Simulating core electron binding energies of halogenated species adsorbed on ice surfaces and in solution with relativistic quantum embedding calculations
Richard A. Opoku, Céline Toubin, André Severo Pereira Gomes
In this work we investigate the effects of the environment on the X-ray photoelectron spectra of hydrogen chloride and the chloride ions adsorbed on ice surfaces, as well as of chl…
Frozen-Density Embedding for including environmental effects in the Dirac-Kohn-Sham theory: an implementation based on density fitting and prototyping techniques
Matteo De Santis, Diego Sorbelli, Valerie Vallet +3
The Frozen Density Embedding scheme represents an embedding method in which environmental effects onto a given subsystem are included by representing the other subsystems making up…
Reassessing the potential of TlCl for laser cooling experiments via four-component correlated electronic structure calculations
Xiang Yuan, André Severo Pereira Gomes
The TlCl molecule has previously been investigated theoretically and proposed as promising candidates for laser cooling searches [X. Yuan et. al. J. Chem. Phys., 149, 094306, 2018]…
Assessing MP2 frozen natural orbitals in relativistic correlated electronic structure calculations
Xiang Yuan, Lucas Visscher, Andre Severo Pereira Gomes
The high computational scaling with the number of correlated electrons and the size of the basis set is a bottleneck which limits applications of coupled cluster (CC) algorithms. T…
Environment effects on X-ray absorption spectra with quantum embedded real-time Time-dependent density functional theory approaches
Matteo De Santis, Valérie Vallet, André Severo Pereira Gomes
In this work we implement the real-time time-dependent block-orthogonalized Manby-Miller embedding (rt-BOMME) approach alongside our previously developed real-time frozen density e…
Predictive simulations of core electron binding energies of halogenated species adsorbed on ice surfaces from relativistic quantum embedding calculations
Richard Asamoah Opoku, Céline Toubin, André Severo Pereira Gomes
We report an investigation of the suitability of quantum embedding for modeling the effects of the environment on the X-ray photoelectron spectra of hydrogen chloride and the chlor…
Electronic Spectra of Ytterbium Fluoride from Relativistic Electronic Structure Calculations
Johann V. Pototschnig, Kenneth G. Dyall, Lucas Visscher +1
We report an investigation of the low-lying excited states of the YbF molecule--a candidate molecule for experimental measurements of the electron electric dipole moment--with 2-co…
The DIRAC code for relativistic molecular calculations
Trond Saue, Radovan Bast, Andre Severo Pereira Gomes +24
DIRAC is a freely distributed general-purpose program system for 1-, 2- and 4-component relativistic molecular calculations at the level of Hartree--Fock, Kohn--Sham (including ran…
Investigating solvent effects on the magnetic properties of molybdate ions (MoO) with relativistic embedding
Loïc Halbert, Małgorzata Olejniczak, Valérie Vallet +1
We investigate the ability of mechanical and electronic density functional theory (DFT)-based embedding approaches to describe the solvent effects on nuclear magnetic resonance (NM…
On the Multi-Reference Nature of Plutonium Oxides: PuO, PuO, PuO and PuO(OH)
Katharina Boguslawski, Florent Réal, Paweł Tecmer +5
Actinide-containing complexes present formidable challenges for electronic structure methods due to the large number of degenerate or quasi-degenerate electronic states arising fro…