A new preprint by Vincent Robert, Giovanni Li Manni and coworkers on Stochastic Difference-Dedicated Configuration Interaction for Magnetic Exchange in Large Active Spaces is now available on ChemRxiv : https://chemrxiv.org/doi/full/10.26434/chemrxiv.15001030/v1

L’article A new preprint by Vincent Robert, Giovanni Li Manni and coworkers est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

Roberto Marquardt and coworkers published a new paper, “Observation and modeling of bound–bound and bound-free transitions in Cu₂” in The Journal of Chemical Physics : https://doi.org/10.1063/5.0312177

Laser-induced transitions from the perturbed J0⁺_u , v′= 0 − 2 ∼ G 0⁺_u , v′= 62 − 68 system to the X¹Σ⁺_g (0⁺_g ) ground state of dicopper havebeen investigated experimentally and theoretically. Upon excitation of specific rotational levels, long progressions to vibrational levels are observed. Strong emissions are observed at low vibrational levels. Notably, spectra show significant line strength near and above the asymptotic atom dissociation limit. The latter feature is due to the Condon internal diffraction of bound-free transitions to the continuum region of the ground state. Based on the Rydberg–Klein–Rees potentials for the J0⁺_u , G0⁺_u , and X¹Σ⁺_g (0⁺_g ) states, eigenvalues and wave functions are obtained by solving the radial Schrödinger equation. Hence, frequencies of rovibrational transitions, Franck–Condon factors, and Einstein coefficients for spontaneous emissions are determined. The required transition dipole moment functions are obtained from high-level electronic structure calculations at the multi-reference configuration-interaction level of theory. Simulated line positions and relative intensities for transitions near and above the dissociation limit are in good agreement with the experiment. Furthermore, the feasibility of photoassociation experiments involving ultracold copper atoms is estimated by calculating the coupling rate between the colliding cold atoms and the excited G0⁺_u state.

L’article A new publication by Roberto Marquardt and coworkers est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

A new preprint by Wafa Makhlouf, Emmanuel Fromager and coworker on Generalized local potential functional embedding theory of localized orbitals is now available on arXiv: https://arxiv.org/abs/2602.15624

L’article A new preprint by Wafa Makhlouf, Emmanuel Fromager and coworker est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

A new preprint by Lucien Dupuy and Emmanuel Fromager on Charged excitations made neutral: N-centered ensemble density functional theory of Fukui functions is now available on arXiv: https://arxiv.org/abs/2601.02985

L’article A new preprint by Lucien Dupuy and Emmanuel Fromager est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

A new preprint by Lucien Dupuy, Emmanuel Fromager and coworker on Exactly factorized molecular Kohn–Sham density functional theory is now available on the arXiv: https://arxiv.org/abs/2601.03972

L’article A new preprint by Lucien Dupuy, Emmanuel Fromager and coworker est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

Vincent Robert and coworkers published a new paper, “Dynamic Electromerism: Correlated Rotational and Cross-Conjugation Dynamics in DAMN (DiAminoMaleoNitrile) and DAFN (DiAminoFumaroNitrile) Derivatives” in the Journal of the American Chemical Society : https://doi-org.scd-rproxy.u-strasbg.fr/10.1021/jacs.5c09269

Conformational dynamics play key roles in molecular reactivity and the development of functional molecular machines. In this study, we investigate the competitive correlation between internal rotations about the C–NR₂ bonds and cross-conjugation dynamics in DAMN, DAFN, and their derivatives. Using a combination of NMR spectroscopy, crystallographic analysis, and computational studies, we demonstrate that conjugation in one of the two push–pull π-systems restricts its own C–N bond rotation while suspending conjugation and facilitating rotation in the other system, leading to synchronized rotation-conjugation oscillation. Variable Temperature (VT)-NMR spectroscopy revealed that the presence of competing cross-conjugated pathways drastically lowers the C–N rotational barriers of the amino groups compared to those of reference compounds presenting a single π-system (11–14 kcal/mol at 298 K). Density functional theory (DFT) studies yielded rotational barriers as low as ∼2 kcal/mol for tetra-methylated DAMN, with a disrotatory mechanism. The introduction of steric effects increased the rotational barriers, yielding measurable NMR values of 7–9 kcal/mol at coalescence in the bulkiest DAMN derivative. Additionally, modulation of the structural desymmetrization of the coupled push–pull systems in monoimine derivatives of DAMN allowed determination of rotational barriers within the range of those of the reference compounds. These effects agreed with the presence of cross-conjugation, which was also supported by X-ray diffraction. The findings provide insight into the structural factors governing rotational barriers in cross-conjugated systems exhibiting correlated molecular motion. Thus, DAMN and DAFN present a dynamic electromerism process where oscillation between two different cross-conjugation pathways is regulated by the C–N rotation frequency.

L’article A new publication by Vincent Robert and coworkers est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

Even Chiari, Wafa Makhlouf, Lucie Pepe, Saad Yalouz and coworkers published a new paper, “Ab initio polaritonic chemistry on diverse quantum computing platforms: Ansatz circuit design for qubit, qudit, and hybrid qubit-qumode architectures” in Physical Review A : https://doi.org/10.1103/1l5j-dfh4

In the field of ab initio polaritonic chemistry, the use of quantum computers may offer, in the long term, a promising computational pathway for simulating and exploring novel cavity-induced light-matter phenomena. Addressing such problems on emerging platforms, however, already presents significant challenges that need to be considered for near-term applications. Within the framework of the variational quantum eigensolver (VQE), a key question concerns the development of quantum circuit Ansätze capable of encoding strongly correlated electron-photon states at a reasonable resource cost. Motivated by this question, in this work we develop different Ansatz strategies covering not only conventional qubit-based approaches but also higher-dimensional information units. Specifically, we introduce a set of circuits tailored to three different quantum computing architectures: (i) qubits, (ii) qudits, and (iii) hybrid qubit-qumode units of information. All circuits are designed to be both compact and physically motivated, with a central element being the development of spin-adapted electron-photon entangling fragment circuits tailored to the native capabilities of each platform. Integrating the different Ansätze within the state-averaged VQE, we numerically benchmark the three strategies on a cavity-embedded H₂ molecule using state-vector simulations. Our results show that each proposed Ansatz achieves high accuracy in encoding the ground, first, and second polaritonic eigenstates of the system, even reproducing characteristic light-matter phenomena such as light-induced avoided crossings and conical intersections. This prospective work, beyond introducing multiple computational strategies adapted to different platforms, also highlights the potential of higher-dimensional quantum architectures to address hybrid fermion-boson systems.

L’article A new publication by Even Chiari, Wafa Makhlouf, Lucie Pepe, Saad Yalouz and coworkers est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

Chantal Daniel and coworkers published a new paper, “Bright Circularly Polarized Electrochemiluminescence from Heterobinuclear Ir^III–Au^I Enantiomers” in Angewandte Chemie : https://doi.org/10.1002/anie.202510787

The development of efficient circularly polarized electrochemiluminescence (CP-ECL) probes is still at its infancy and examples are still very limited. Yet, their achievement would enable gathering a readout that carries privileged information on the probe’s chiral environment by monitoring luminescence polarization bias with high signal-to-noise ratio. Notwithstanding, this is a highly challenging task and requires judicious chemical engineering of chiral ECL-active emitters. Herein, we aim at expanding the palette of CP-ECL luminophores by presenting a novel class of enantiopure heterobinuclear Ir(III)–Au(I) complexes, which are investigated thoroughly by means of chemical, structural, and (chiro-)optical techniques. The ground and excited state properties are also elucidated by using density functional theory (DFT) approaches including spin-orbital coupling (SOC) perturbation. The chiral-at-metal complexes display luminescence with a polarization bias of the emitted light that is function of the helical arrangement of the coordination sphere around the Ir(III) center. Overall, the photo- and electro-active complexes unraveled in this work combine unparallelly high photoluminescence quantum yield in the orange region, excellent circularly polarized luminescence (CPL) brightness up to 4.5 M⁻¹ cm⁻¹ with a notable ECL activity. Finally, these features provide emitters with CP-ECL efficiency that encompass remarkably by a factor 3.5 that of the well-known benchmark tris-(2,2′-bipyridyl)ruthenium(II).

L’article A new publication by Chantal Daniel and coworkers est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

Wafa Makhlouf, Emmanuel Fromager and coworker published a new paper, “Local Potential Functional Embedding Theory of Molecular Systems: Localized Orbital-Based Embedding from an Exact Density-Functional Perspective” in Journal of Chemical Theory and Computation : https://doi.org/10.1021/acs.jctc.5c01256

Localized orbital-based quantum embedding, as originally formulated in the context of density matrix embedding theory (DMET), is revisited from the perspective of lattice density functional theory (DFT). An in-principle exact (in the sense of full configuration interaction) formulation of the theory, where the occupations of the localized orbitals play the role of the density, is derived for any (model or ab initio) electronic Hamiltonian. From this general formalism we deduce an exact relation between the local Hartree-exchange-correlation (Hxc) potential of the full-size Kohn–Sham (KS) lattice-like system and the embedding chemical potential that is adjusted on each embedded fragment, individually, such that both KS and embedding cluster systems reproduce the exact same local density. When well-identified density-functional approximations (that find their justification in the strongly correlated regime) are applied, a practical self-consistent local potential functional embedding theory (LPFET), where the local Hxc potential becomes the basic variable, naturally emerges from the theory. LPFET differs from previous density embedding approaches by its fragment-dependent embedding chemical potential expression, which is a simple functional of the Hxc potential. Numerical calculations on prototypical systems show the ability of such an ansatz to improve substantially the description of density profiles (localized orbitals occupation numbers in this context) in strongly correlated systems.

L’article A new publication by Wafa Makhlouf, Emmanuel Fromager and coworker est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.

Lucie PEPE defended her PhD on Friday 3rd October in the morning. She was supervised by Vincent ROBERT and Saad YALOUZ.

Thesis topic: Quantum Transport and Light-Matter Interaction in Complex Molecular Systems

Congratulations to her !!

L’article Congratulations to Lucie PEPE ! est apparu en premier sur Laboratoire de Chimie Quantique de Strasbourg.