Article
Chemistry, Multidisciplinary
J. Patrick Zobel, Anna M. Wernbacher, Leticia Gonzalez
Summary: The mechanism of reverse intersystem crossing (rISC) in metal-based TADF emitters is still not clear, as the small singlet/triplet energy gaps necessary for thermal rISC in donor-acceptor systems with charge-transfer excited states have spin-orbit couplings that are too small for effective rISC. In this study, the first nonadiabatic dynamics simulation of rISC process in a carbene-copper(I)-carbazolyl TADF emitter is reported. Efficient rISC on a picosecond time scale is demonstrated, involving an intermediate higher-lying triplet state of metal-to-ligand charge transfer character ((MLCT)-M-3) that enables large spin-orbit couplings with the lowest singlet charge transfer state. The mechanism is completed in the S-1 state where the complex can return to a co-planar coordination geometry with high fluorescence efficiency.
ANGEWANDTE CHEMIE-INTERNATIONAL EDITION
(2023)
Article
Chemistry, Physical
Pablo Roseiro, Nadia Ben Amor, Vincent Robert
Summary: The spin states of a Co(II) oxoverdazyl compound are investigated in this study. The results show a mixture of low-spin and high-spin states, which is influenced by the structure of the coordination sphere. This finding has significant implications for molecular magnetism.
Article
Chemistry, Applied
Thibault Pariat, Pauline M. Verite, Denis Jacquemin, Julien Massue, Gilles Ulrich
Summary: A dual-emissive fluorophore, HBBODipic, with an Excited-State Intramolecular Proton Transfer (ESIPT) process has been described. It has been used for generating panchromatic white-emission and ratiometric detection of substrates.
Article
Chemistry, Multidisciplinary
Rodolphe Pollet, Wutharath Chin
Summary: The photochemistry of oxocarboxylic acids plays a significant role in atmospheric chemistry. Pyruvic acid, when in the presence of sodium cation or its conjugate base, shows altered hydration equilibrium and photosensitivity to UV-visible light. Through ab initio metadynamics simulation, we reveal the reversible hydration reaction mechanism between the keto and diol forms of pyruvic acid, influenced by sodium, and provide insights into the photoactivity of these forms in the actinic region through calculations of electronic transition energies.
CHEMISTRY-A EUROPEAN JOURNAL
(2023)
Article
Biochemistry & Molecular Biology
Michal F. Rode, Daniela Nedeltcheva-Antonova, Liudmil Antonov
Summary: This study investigates in depth the ground state proton transfer and isomerization properties of two tautomeric Schiff bases, as well as calculates the excited state energy profiles. The obtained results are discussed in light of existing experimental data.
Article
Chemistry, Multidisciplinary
Thibault Pariat, Maxime Munch, Martyna Durko-Maciag, Jaroslaw Mysliwiec, Pascal Retailleau, Pauline M. Verite, Denis Jacquemin, Julien Massue, Gilles Ulrich
Summary: HBX fluorophores are well-known for their synthetic versatility, photostability, and strong solid-state fluorescence. However, their performance is heavily quenched in solution due to efficient non-radiative pathways. In this study, a simple structural modification of the heteroring in HBX dyes led to significant changes in emission color, dual emission engineering, and fluorescent quantum yield, showing promising abilities as bright dual-state emitters in both solution and solid state.
CHEMISTRY-A EUROPEAN JOURNAL
(2021)
Article
Materials Science, Multidisciplinary
Luke J. Wirth, Christopher Woodward, Amir A. Farajian
Summary: Advances in first principles methods are used to study the atom-vacancy exchanges near a screw dislocation in fcc Ni, revealing direction-dependent free energy profiles and temperature-dependent correlation effects. The dynamic approach shows intra-cell energy profile asymmetry related to dynamic geometry rearrangements. Despite absolute values of rate constants being similar, the HTST method generally underestimates rates by a factor of 2-5, partially explaining discrepancies between theoretical works and experiments in pipe diffusion diffusivities.
Article
Chemistry, Physical
Juan J. J. Aucar, Alejandro F. F. Maldonado, Juan I. I. Melo
Summary: In this work, relativistic corrections to the electric field gradient (EFG) are presented, including spin-dependent corrections for the first time. The results show that these new corrections significantly improve the performance of the existing method and are in close agreement with calculations at the four-component Dirac-Hartree-Fock (4c-DHF) level. The accuracy of the EFG values obtained with this new method allows for the analysis of the electronic origin of relativistic effects using well-known nonrelativistic operators.
JOURNAL OF CHEMICAL PHYSICS
(2022)
Article
Biochemistry & Molecular Biology
Beata Vranovicova, Roman Boca
Summary: Ten amino acids were studied using quantum chemical calculations, evaluating various properties and correlations through statistical multivariate methods. Thermochemical properties were also assessed at 300 K.
JOURNAL OF MOLECULAR MODELING
(2021)
Article
Chemistry, Physical
Henrik H. Kristoffersen
Summary: An explicit charging approach is introduced in atomic level electrochemistry modeling to account for constant potential. This method allows for calculating electrochemical reaction barriers and reproducing results from the computation hydrogen electrode (CHE) approach under constant potential conditions. The approach is used to obtain activation and adsorption free energies for proton adsorption from a static water bilayer to the Cu(111) surface.
Article
Biochemistry & Molecular Biology
Natalia Grytsyk, Ludovic Richert, Pascal Didier, Dmytro Dziuba, Stefano Ciaco, Viola Mazzoleni, Thiebault Lequeu, Mattia Mori, Yitzhak Tor, Lara Martinez-Fernandez, Roberto Improta, Yves Mely
Summary: Time-resolved fluorescence anisotropy (TRFA) technique provides important information on the dynamics of biomolecules and their interaction with ligands. This study shows that thienoguanosine ((th)G), a fluorescent analogue of guanosine, overcomes the limitations of non-fluorescent natural nucleosides and serves as a unique reporter for investigating the rotational dynamics of dsDNA and protein/dsDNA complexes.
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
(2022)
Article
Chemistry, Organic
Timothee Stoerkler, Denis Frath, Denis Jacquemin, Julien Massue, Gilles Ulrich
Summary: The optical properties of synthesized salicylaldehyde derivatives were investigated, showing significant fluorescence effects in both solution and solid-state, with Excited-State Intramolecular Proton Transfer (ESIPT) fluorescence. Modifying the spacer triggered major differences in terms of maximum emission wavelength and fluorescence quantum yields in various media.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2021)
Article
Chemistry, Organic
Timothee Stoerkler, Thibault Pariat, Adele D. Laurent, Denis Jacquemin, Gilles Ulrich, Julien Massue
Summary: This article describes various synthetic pathways to introduce sterically hindered substituents to the proton donor side of ESIPT-capable fluorophores. It also investigates the influence of solvent properties on the optical properties of the dyes. The study confirms that ESIPT fluorophores do not undergo pi-stacking in the solid-state.
EUROPEAN JOURNAL OF ORGANIC CHEMISTRY
(2022)
Article
Chemistry, Physical
Jing Shang, Congxin Xia, Chun Tang, Chun Li, Yandong Ma, Yuantong Gu, Liangzhi Kou
Summary: The bending deformation of AgBiP2Se6 monolayers can manipulate the polarization direction and domain size, significantly improving the ferroelectric stability. This mechano-ferroelectric coupling represents a new mechanism for stabilization and polarization flip in 2D ferroelectrics, with potential applications in next-generation non-volatile storage devices.
NANOSCALE HORIZONS
(2021)
Article
Spectroscopy
O. Palumbo, A. Paolone, M. Campetella, F. Ramondo, F. Cappelluti, L. Gontrani
Summary: A detailed study on the conformational landscape of chloromethyl-oxirane and chloromethyl-thiirane was conducted using a combination of experimental and theoretical methods. The study successfully interpreted high-quality infrared spectroscopy measurements, with ab initio Molecular Dynamics simulations, anharmonic frequencies, and free energy calculations. The modulation of conformational equilibrium upon the addition of solvents was computationally evaluated, confirming results in experimental measurements.
SPECTROCHIMICA ACTA PART A-MOLECULAR AND BIOMOLECULAR SPECTROSCOPY
(2021)