We demonstrate that collective vibrational strong coupling of molecules in thermal equilibrium can give rise to significant local electronic polarizations the thermodynamic limit. do so by first showing full nonrelativistic Pauli–Fierz problem an ensemble strongly coupled dilute-gas limit reduces cavity Born–Oppenheimer approximation a cavity–Hartree equation for structure. Consequently, each individual molecule experiences self-consistent dipoles all other molecules, which amount...

We analyze how the photorelaxation dynamics of a molecule can be controlled by modifying its electromagnetic environment using nanocavity mode. In particular, we consider RNA nucleobase uracil, which is natural mechanism to prevent photodamage. our theoretical work, identify operative conditions in strong coupling with cavity mode open an efficient photoprotective channel, resulting relaxation twice as fast one. rely on state-of-the-art chemically detailed molecular model and non-Hermitian...

Experimental studies indicate that optical cavities can affect chemical reactions through either vibrational or electronic strong coupling and the quantized cavity modes. However, current understanding of interplay between molecules confined light modes is incomplete. Accurate theoretical models take into account intermolecular interactions to describe ensembles are therefore essential understand mechanisms governing polaritonic chemistry. We present an ab initio Hartree-Fock ansatz in...

The rates and outcomes of virtually all photophysical photochemical processes are determined by Conical Intersections. These regions degeneracy between electronic states on the nuclear landscape molecules where electrons nuclei evolve comparable timescales become strongly coupled, enabling radiationless relaxation channels upon optical excitation. Due to their ultrafast nature vast complexity, monitoring Intersections experimentally is an open challenge. We present a simulation study...

Recent experiments have revealed the profound effect of strong light-matter interactions in optical cavities on electronic ground state molecular systems. This phenomenon, known as vibrational coupling, can modify reaction rates and induce formation polaritons, hybrid states involving both photon modes, modes molecules. We present an ab initio methodology based cavity Born-Oppenheimer Hartree-Fock ansatz, which is specifically powerful for ensembles molecules, to calculate vibro-polaritonic...

Strong coupling of molecules with quantized electromagnetic fields can reshape their potential energy surfaces by forming dressed states. In such a scenario, it is possible to manipulate the dynamics molecule and open new photochemical reaction pathways. A theoretical approach describe coupled molecular-photon systems Cavity-Born-Oppenheimer (CBO) approximation. Similarly standard Born-Oppenheimer (BO) approximation, system partitioned electronic part treated quantum mechanically. This...

As pioneering experiments have shown, strong coupling between molecular vibrations and light modes in an optical cavity can significantly alter properties even affect chemical reactivity. However, the current theoretical description is limited far from complete. To explore origin of this exciting observation, we investigate how structure changes under light-matter using ab initio method based on Born-Oppenheimer Hartree-Fock ansatz. By optimizing H2O H2O2 resonantly coupled to modes, study...

Quantum chemical calculations reveal that excited thiophene decays <italic>via</italic> a low lying conical intersection seam. In oligothiophenes barriers inhibit this passage while deactivation pathways intersystem crossing channels open.

<italic>Ab initio</italic> on-the-fly molecular dynamics reveals that excited thiophene decays <italic>via</italic> low lying conical intersections and intersystem crossing. Open-ring structures are responsible for the observed long life times.

Strong coupling of organic molecules to the vacuum field a nanoscale cavity can be used modify their chemical and physical properties. We extend Tavis-Cummings model for molecular ensembles show that often neglected interaction terms arising from static dipole moment self-energy are essential correct description light-matter in polaritonic chemistry. On basis full quantum description, we simulate excited-state dynamics spectroscopy MgH$^+$ resonantly coupled an optical cavity. inclusion...

Benzophenone serves as a prototype chromophore for studying the photochemistry of aromatic ketones, with applications ranging from biochemistry to organic light-emitting diodes. In particular, its intersystem crossing first singlet excited state triplet states has been extensively studied, but experimental or theoretical studies on preceding internal conversion within manifold are very rare. This relaxation mechanism is particularly important because direct population transfer ground...

The ability to control chemical reactions by coupling organic molecules confined light in a cavity has recently attracted much attention. While most previous studies have focused on single-mode photonic or plasmonic cavities, here we investigate the effect of hybrid metallodielectric cavities photoisomerization reactions. Hybrid which support both and modes, offer unique opportunities that arise from interplay between these two distinct types modes. In particular, demonstrate interference...

Despite recent numerical evidence, one of the fundamental theoretical mysteries polaritonic chemistry is how and if collective strong coupling can induce local changes electronic structure to modify chemical properties. Here we present nonperturbative analytic results for a model system consisting an ensemble <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mi>N</a:mi></a:math> harmonic molecules under vibrational (VSC) that alters our understanding this question. By applying cavity...

Tyrosinase model systems pinpoint pathways to translating Nature's synthetic abilities for useful catalysts. Mostly, they use N-donor ligands which mimic the histidine residues coordinating two copper centres. Copper complexes with bis(pyrazolyl)methanes pyridinyl or imidazolyl moieties are already reported as excellent tyrosinase models. Substitution of donor results in new ligand HC(3-tBuPz)2 (4-CO2 MePy) stabilises a room-temperature stable μ-η2 :η2 -peroxide dicopper(II) species upon...

We demonstrate that collective vibrational strong coupling of molecules in thermal equilibrium can give rise to significant local electronic polarizations the thermodynamic limit. do so by first showing full non-relativistic Pauli-Fierz problem an ensemble strongly-coupled dilute-gas limit reduces cavity Born-Oppenheimer approximation a cavity-Hartree equation for structure. Consequently, each individual molecule experiences self-consistent dipoles all other molecules, which amount...

Protons in low-barrier superstrong hydrogen bonds are typically delocalized between two electronegative atoms. Conventional methods to characterize such vibrational spectroscopy and diffraction techniques. We introduce soft X-ray uncover the electronic fingerprints for proton sharing protonated imidazole dimer, a prototypical building block enabling effective transport biology high-temperature fuel cells. Using nitrogen core excitations as sensitive probe protonation status, we identify...

Strong coupling of organic molecules to the vacuum field a nanoscale cavity can be used modify their chemical and physical properties. We extend Tavis–Cummings model for molecular ensembles show that often neglected interaction terms arising from static dipole moment self-energy are essential correct description light–matter in polaritonic chemistry. On basis full quantum description, we simulate excited-state dynamics spectroscopy MgH+ resonantly coupled an optical cavity. inclusion moments...

We present a nonadiabatic dynamics study concerning the subpicosecond relaxation of excited states in dimeric and trimeric thiophene chains. The influence triplet overall process is, for first time, taken into account by explicitly including spin–orbit couplings hence allowing intersystem crossing phenomena. observe fundamental role state manifold driving full process. In particular we evidence effect both, inter-ring rotation ring-opening, process, as compared to monomer, where ring-opening...

Conical intersections are ubiquitous in chemical systems but, nevertheless, extraordinary points on the molecular potential energy landscape. They provide ultra-fast radiationless relaxation channels, their topography influences product branching, and they equalize timescales of electron nuclear dynamics. These properties reveal optical control possibilities few femtosecond regime. In this theoretical study, we aim to explore options that rely carrier envelope phase a few-cycle IR pulse. The...

Attosecond extreme ultraviolet (XUV) and soft x-ray sources provide powerful new tools for studying ultrafast molecular dynamics with atomic, state, charge specificity. In this report, we employ attosecond transient absorption spectroscopy (ATAS) to follow strong-field-initiated in vinyl bromide. Probing the Br M edge allows one assess competing processes neutral ionized species. Using ab initio non-adiabatic dynamics, simulate cationic resulting from interaction of molecule strong field....

We have investigated nuclear dynamics in bound and dissociating acetylene molecular ions a time-resolved reaction microscopy experiment with pair of few-cycle pulses. Vibrating cations or dications are produced by the first pulse. The second pulse probes ionization to higher charge states Coulomb explosion molecule. For cations, we observed vibrations (HCCH) its isomer vinylidene (CCHH) along CC-bond periodicity around 26 fs. dication molecules, clear indication enhanced is found occur CH-...

Photo-initiated processes in molecules often involve complex situations where the induced dynamics is characterized by interplay of nuclear and electronic degrees freedom. The interaction molecule with an ultrashort laser pulse or coupling at a conical intersection (CoIn) induces coherent electron which subsequently modified motion. typically leads to fast decoherence but also, depending on system, enables reappearance dynamics. We study this situation for photo-induced nucleobase uracil....

Ultrafast optical techniques allow us to study ultrafast molecular dynamics involving both nuclear and electronic motion. To support interpretation, theoretical approaches are needed that can describe the electron dynamics. Hence, we revisit expand our ansatz for coupled description of in systems (NEMol). In this purely quantum mechanical ansatz, quantum-dynamical motion is combined with calculation eigenfunction basis. The NEMol applied simulate molecule NO2 vicinity a conical intersection...

As pioneering experiments have shown, strong vibrational coupling between molecular vibrations and light modes in an optical cavity can significantly alter properties even affect chemical reactivity. However, the current theoretical description is limited far from complete. To explore origin of this exciting observation, we investigate how structure changes under light-matter using ab-initio method based on Born-Oppenheimer Hartree-Fock ansatz. By optimizing H$_2$O H$_2$O$_2$ resonantly...