Article
Chemistry, Multidisciplinary
Oksana Travnikova, Tomislav Pitesa, Aurora Ponzi, Marin Sapunar, Richard James Squibb, Robert Richter, Paola Finetti, Michele Di Fraia, Alberto De Fanis, Nicola Mahne, Michele Manfredda, Vitali Zhaunerchyk, Tatiana Marchenko, Renaud Guillemin, Loic Journel, Kevin Charles Prince, Carlo Callegari, Marc Simon, Raimund Feifel, Piero Decleva, Nada Doslic, Maria Novella Piancastelli
Summary: This article investigates the photochemically induced ring-opening isomerization reaction of 1,3-cyclohexadiene to 1,3,5-hexatriene, revealing a more complex evolution of the excitation-deexcitation process than previously described.
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
(2022)
Article
Physics, Multidisciplinary
Alexander Poshakinskiy, Alexander N. Poddubny
Summary: In this study, we investigate subradiant states in an array of atoms coupled to photons propagating in a one-dimensional waveguide, focusing on the strongly interacting many-body regime with large excitation fill factor f. By introducing a generalized many-body entropy of entanglement and using exact numerical diagonalization followed by high-order singular value decomposition, we are able to visualize and understand the structure of a many-body quantum state. Our findings reveal the breakdown of fermionized subradiant states with the increase of f, the emergence of short-ranged dimerized antiferromagnetic correlations at the critical point f = 1/2, and the complete disappearance of subradiant states at f > 1/2.
PHYSICAL REVIEW LETTERS
(2021)
Article
Chemistry, Applied
Levon S. Atabekyan, Alexandra Ya Freidzon, Alexander K. Chibisov, Sergey P. Gromov, Sergey Z. Vatsadze, Vyacheslav N. Nuriev, Alexey Medvedko
Summary: This study focused on the photoprocesses of bis(18-crown-6)-1,3-distyrylbenzene (DSB) and its complexes with barium and lead perchlorates in a MeCN-CH2Cl2 mixture. Triplet DSB complexes were found to play a role in radiationless deactivation and fluorescence processes, with the most effective intersystem crossing observed in the lead perchlorate complex. Quantum chemistry was used to calculate geometric structures and absorption spectra, providing explanations for the observed results.
Article
Chemistry, Multidisciplinary
Maarten Stam, Indy du Fosse, Ivan Infante, Arjan J. Houtepen
Summary: This study provides theoretical insight into the effect of electron charging on InP QDs and proposes a method to avoid trap state formation during the charging process.
Article
Chemistry, Physical
Minita Ojha, Mandala Anitha, Raj K. Bansal
Summary: The reaction of 3-benzylbenzothiazolium bromide with triethylamine initially produces two products, but only one compound is obtained after purification, which is consistent with a previous report. Theoretical investigation reveals two possible reaction pathways, with the second step being the rate-determining step and the obtained product having lower activation free energy barriers. Additionally, the two isomers are found to be atropisomers separated by a small activation free energy barrier.
JOURNAL OF MOLECULAR STRUCTURE
(2021)
Article
Physics, Multidisciplinary
J. S. Ochs, D. K. J. Boness, G. Rastelli, M. Seitner, W. Belzig, M. I. Dykman, E. M. Weig
Summary: Phononic frequency combs have been attracting increasing attention as a new type of nonlinear phenomenon and their potential applications. This study demonstrates the generation of a frequency comb by a single nanomechanical mode driven by a resonant monochromatic drive. The observed comb emerges at weak drive conditions, suggesting the presence of a negative nonlinear friction induced by the resonant drive. These findings go beyond the field of nanomechanics and present a new approach to generate tunable frequency combs in single-mode vibrational systems.
Article
Chemistry, Physical
Weitao Yang, Jiachen Li, Dorothea Golze
Summary: In this study, the renormalized singles (RS) Green's function is applied in the Bethe-Salpeter equation (BSE)/GW approach to accurately predict neutral excitation energies of molecular systems. The BSE/GRSWRS method significantly outperforms other approaches in terms of accuracy and eliminates the dependence on the choice of density functional approximation.
JOURNAL OF CHEMICAL THEORY AND COMPUTATION
(2022)
Article
Chemistry, Physical
Nadia Ben Amor, Eric Michoulier, Aude Simon
Summary: This study focuses on the theoretical investigation of the influence of water clusters' organization and size on the electronic spectrum of an interacting benzene molecule using TD-DFT and CASPT2 methods. The results show that electronic transitions are dependent on the cluster structure, particularly in small systems. Low energy transitions from a benzene pi orbital to a virtual orbital of Rydberg character were found to play a role in the photochemistry of aromatic species when interacting with water clusters or ice.
THEORETICAL CHEMISTRY ACCOUNTS
(2021)
Article
Physics, Atomic, Molecular & Chemical
A. H. Davtyan, Z. O. Manukyan, S. D. Arsentev, L. A. Tavadyan, V. S. Arutyunov
Summary: Quantum chemical calculations using the B3LYP method and the CBS-QB3 method were carried out to study the potential energy surfaces (PESs) of systems containing ethylene, hydrogen, and oxygen atoms. The enthalpy diagram shows that the addition of a hydrogen atom to ethylene occurs through the formation of a van der Waals complex. The enthalpy diagrams of decomposition and isomerization of the ethoxyl radical are presented, and the probabilities of their occurrence are analyzed. The global PES minimum of the system is the hydroxyethyl radical, and possible pathways for further transformation are discussed.
RUSSIAN JOURNAL OF PHYSICAL CHEMISTRY B
(2023)
Article
Optics
Peng Xu, Qingli Jing, Peng Zhao, Yang Yu
Summary: In this study, we analyze a high-fidelity two-qutrit gate using microwave pulses on fixed-frequency superconducting transmon qutrits and show that a high-fidelity iSWAP-like gate can be achieved. We employ perturbation theory to derive an effective interaction Hamiltonian and estimate the gate time for the two-qutrit system. By employing a microwave-activation scheme, we can realize a high-fidelity iSWAP-like gate on different excited states of the two qutrits.
Article
Physics, Multidisciplinary
Jurg Frohlich, Zhou Gang
Summary: This paper reviews the ideas and results in quantum experiments. It first recalls an example of an indirect measurement experiment and its theoretical interpretations. The von Neumann and Luders measurement postulates in the Copenhagen interpretation of quantum mechanics are then discussed. A model proposed by Gisin is described and used to provide a theoretical description of the experiment. Technical issues in the analysis of Gisin's model are elaborated upon, and a general principle for the stochastic time evolution of individual physical systems is given to solve the measurement problem in quantum mechanics.
ANNALES HENRI POINCARE
(2023)
Article
Chemistry, Physical
Siby Thomas, Sruthi Thulaseedasan, Mohsen Asle Zaeem
Summary: The effects of surface terminal groups on the structural, mechanical, and electronic properties, as well as the quantum capacitance of Ca2CT2 MXenes were investigated using first-principles electronic structure computations. The results showed that the surface terminations greatly influenced the work function, electron density of states, and quantum capacitance of the MXenes. Ca2CCl2 exhibited the highest quantum capacitance among the studied cases.
Article
Chemistry, Physical
Sergey Doronin, Yury A. Budkov, Daniil M. Itkis
Summary: Based on the quantum-mechanical theory of electron transfer, a parameter was proposed to describe the electrochemical activity of doped graphenes, calculated using density of states and local density of state values obtained from density functional theory calculations, as well as reorganization energies of the redox system. The study showed that the proposed activity parameter correlates well with calculated ET rate constants, and the influence of doped elements on graphene activity follows a certain order in the oxygen reduction reaction.
Article
Chemistry, Physical
Alvaro Perez-Barcia, Angeles Pena-Gallego, Marcos Mandado
Summary: This study reveals the transition of [1,3] sigmatropic rearrangement mechanisms from high-barrier pericyclic to barrierless pseudopericyclic through multicenter electron delocalization analysis. A good correlation between barrier and four-center electron delocalization at the transition state is found, with the barrier independent of bond strength. Insights into the effects of atom substitution and group functionalization are extracted from the analysis.
JOURNAL OF PHYSICAL CHEMISTRY A
(2021)
Article
Chemistry, Multidisciplinary
Wojciech Piotr Oziminski, Igor Wisniewski
Summary: The tautomeric equilibrium of sildenafil molecule was studied using density functional theory methods, revealing that the B tautomer is dominant in both gas phase and water environment, with the C tautomer being energetically unfavorable. The A tautomer is present in small amounts in water solution.
STRUCTURAL CHEMISTRY
(2021)