Article
Physics, Multidisciplinary
Xiaofan Zhang, Xiaomeng Ma
Summary: We theoretically investigate the photoelectron momentum distributions of 1s and 2p(x, y) states of hydrogen by twisted attosecond X waves carrying orbital angular momentum based on first-order perturbation theory. The photoionization spectra as a function of photoelectron energy and emission angle are analyzed respectively. The results indicate that there are interference fringes in the energy spectra and more nodes in the angular distributions. These angular nodes are attributed to both orbital structure and the temporal-spatial structure of X waves. We derive an equation that can quantitatively describe the angular nodes in the photoelectron angular distributions. Our results and analyses indicate that the angular distribution is an important observation for the investigation of the information of both orbitals and X waves.
FRONTIERS IN PHYSICS
(2023)
Article
Chemistry, Physical
Cate S. Anstoter, Jan R. R. Verlet
Summary: Photographing the pyramidal sulphite radical monoanion in the photon energy range of 3.10-4.45 eV revealed two features corresponding to the formation of the ground electronic state of the neutral and thermionic emission. Vibrational structures associated with the umbrella mode of the neutral were observed in the photoelectron spectra and angular distributions. The observed thermionic emission was attributed to the excitation of degenerate Feshbach resonances that can internally convert and statistically emit electrons.
Article
Biochemistry & Molecular Biology
Aurora Ponzi, Marin Sapunar, Nadja Doslic, Piero Decleva
Summary: The molecular frame photoelectron angular distribution (MFPAD) provides information about the electronic structure of the studied system. MFPADs are characteristic signatures of the final ionic states and are highly sensitive to the nature of the final state.
Article
Instruments & Instrumentation
Chrisy Sparling, Alice Ruget, Jonathan Leach, Dave Townsend
Summary: The inverse Abel transform is widely used in charged particle imaging, but it has limitations due to cylindrical symmetry constraints. This study shows how artificial neural networks can replace the inverse Abel transform and directly reconstruct 2D projections into 3D distributions.
REVIEW OF SCIENTIFIC INSTRUMENTS
(2022)
Article
Chemistry, Physical
Andres F. Ordonez, Olga Smirnova
Summary: In this study, we discuss how tensorial observables in photoelectron angular distributions can enable chiral discrimination without chiral light. We derive selection rules and provide explicit expressions, and find enantiosensitive non-dichroic coefficients that are independent of the relative phase between colors, which can be used for studying molecular enantiomers.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Chemistry, Physical
Ruaridh Forbes, Paul Hockett, Ivan Powis, John D. Bozek, Stephen T. Pratt, David M. P. Holland
Summary: Linearly polarized synchrotron radiation was used to record polarization dependent, non-resonant Auger electron spectra of XeF2, revealing the angular distribution characteristics and intrinsic anisotropy parameters of Auger electrons. Experimental results showed that the kinetic energy of electrons measured in resonantly excited spectra for a specific Auger transition is higher than that in directly ionized spectra.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Correction
Chemistry, Physical
Remi Dupuy, Jakob Filser, Clemens Richter, Robert Seidel, Florian Trinter, Tillmann Buttersack, Christophe Nicolas, John Bozek, Uwe Hergenhahn, Harald Oberhofer, Bernd Winter, Karsten Reuter, Hendrik Bluhm
Summary: This study corrects the view of the sensitivity of photoelectron angular distributions to the surfactant layer structure at the liquid-vapor interface proposed by Dupuy et al.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2023)
Article
Chemistry, Physical
Min Zhou, Bo-Wen Si, Jie Yu, Shu-Lin Cong
Summary: This study investigates the asymmetrical photoelectron angular distribution (PAD) in the ionization of NaK molecules using pump-probe femtosecond laser pulses. The results show that the carrier-envelope phase (CEP) of the laser pulse and the molecular orientation have a significant impact on PAD. Different molecular orientations correspond to different PADs, and a strong asymmetry is mainly caused by a larger molecular orientation in the excited state. Uni-directional photoionization can be achieved by adjusting the CEP of the laser pulse and controlling the molecular orientation in the ground state. Additionally, the duration of the laser pulse also affects the PAD.
Article
Optics
Y. Boran, N. Hart, N. Kaya, J. Zhou, A. A. Kolomenskii, H. A. Schuessler
Summary: The study showed that sodium atoms undergo multi-step ionization through various intermediate levels when photo-ionized with intense short laser pulses, resulting in different energy spectra of photoelectrons. Photoelectron angular distributions (PADs) exhibited distinct features for different ATI orders, with main lobes around 60 degrees from the laser polarization and additional lobes becoming more pronounced with increasing ATI peak number. By fitting experimental PADs with Legendre polynomials, the contributions of ionization channels to observed ATI orders were evaluated, showing good agreement with the experimental data.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Optics
Margaret Gregory, Paul Hockett, Albert Stolow, Varun Makhija
Summary: A theory and method for matrix-based reconstruction of molecular frame photoelectron angular distributions from laboratory frame measurements is developed and applied to nonlinear polyatomic molecules. This new technique does not require determination of photoionization matrix elements and allows successful reconstruction of MF photoelectron angular distributions.
JOURNAL OF PHYSICS B-ATOMIC MOLECULAR AND OPTICAL PHYSICS
(2021)
Article
Physics, Multidisciplinary
S. Fritzsche, J. Hofbrucker
Summary: The biharmonic photoionization of atomic inner-shell electrons is an important tool for studying nonlinear light-atom interactions. By controlling the frequency and polarization of the biharmonic beams, the photoelectron angular distribution can be shaped and the resolution of ionization measurements can be enhanced. The angular distribution of the photoelectrons is sensitive to the intensity, phase difference, and temporal structure of the incoming beams. Tuning the properties of the biharmonic field allows for unprecedented control over the angular distribution and elliptical dichroism. These investigations have potential applications in extracting photoionization amplitudes or phase differences of incoming beams.
NEW JOURNAL OF PHYSICS
(2022)
Article
Multidisciplinary Sciences
Joshua Vogwell, Laura Rego, Olga Smirnova, David Ayuso
Summary: We present an ultrafast all-optical approach for efficient chiral recognition based on the interference between sum-frequency generation and third-harmonic generation. Our method encodes the handedness of the medium in the intensity of the emitted harmonic signal, enabling full control over the enantiosensitive response. By manipulating the sub-optical-cycle oscillations of the driving laser field, we achieve high efficiency in chiral sensitivity via low-order nonlinear light-matter interactions, paving the way for ultrafast and highly efficient imaging and control of chiral molecules.
Article
Optics
Rong-Rong Wang, Mao-Yun Ma, Jun-Ping Wang, Zhong Guan, Zhi-Hong Jiao, Wei Li, Guo-Li Wang, Jian-Hong Chen, Song-Feng Zhao
Summary: In this theoretical study, the orbital-resolved photoelectron momentum distributions (PMDs) of neon atoms in time-delayed bichromatic elliptically polarized attosecond pulses were analyzed. The interference patterns in the PMDs were found to be sensitive to various parameters of the attosecond pulses, offering possibilities for controlling interference in atoms by shaping the pulses.
EUROPEAN PHYSICAL JOURNAL D
(2022)
Article
Physics, Multidisciplinary
Si-Qi Zhang, Qi Zhen, Zhi-Jie Yang, Jun Zhang, Ai-Hua Liu, Kai-Jun Yuan, Xue-Shen Liu, Jing Guo
Summary: The ultrafast photoionization dynamics of N-2 molecules by x-ray/XUV laser pulses was investigated, showing the appearance and disappearance of molecular photoionization diffraction at different laser wavelengths, as well as changes in the molecular frame photoelectron momentum distributions and angular distributions.
Article
Chemistry, Physical
Christopher C. Blackstone, Adam A. Wallace, Andrei Sanov
Summary: In this study, photoelectron imaging was used to investigate the angular distributions in HO(2)(-)photodetachment and analyze the transitions and model behaviors of parent anion molecular orbitals. Comparisons with NO(-) and O-2(-) were made to understand the effects of molecular symmetry and chemical bonding structures on photoelectron angular distributions.
Article
Chemistry, Physical
Luca Sementa, Marta Monti, Daniele Toffoli, Alvaro Posada-Amarillas, Mauro Stener, Alessandro Fortunelli
Summary: This study computationally analyzes the optical absorption and photodecay processes of two subnanometer metal complexes on an oxide support. It reveals that complexes with bicarbonate and fluorocarbonate groups are sensitive to optical adsorption, often leading to ligand detachment and/or cluster disaggregation, possibly explaining previous experimental observations. Additionally, the study provides methodological tools to explore this novel field using time-dependent density-functional theory.
JOURNAL OF PHYSICAL CHEMISTRY C
(2021)
Article
Nanoscience & Nanotechnology
Hao Yang, Fabio Ribeiro Negreiros, Qintao Sun, Miao Xie, Luca Sementa, Mauro Stener, Yifan Ye, Alessandro Fortunelli, William A. Goddard, Tao Cheng
Summary: This study provides a method to validate the reactive intermediates in the CO2 electroreduction reaction by predicting the core-level shifts and carefully considering solvation effects and applied voltage. The results could guide future experiments to verify and interpret the reaction mechanism of CO2RR.
ACS APPLIED MATERIALS & INTERFACES
(2021)
Article
Chemistry, Physical
D. Catone, N. Zema, T. Prosperi, M. Stener, P. Decleva, P. Nitti, S. Turchini
Summary: This work addresses the influence of a conformational population in the modeling of photoelectron circular dichroism (PECD) spectroscopy. PECD has revealed a rich and complex phenomenology in molecular processes, especially in molecular geometry sensitivity. The study focuses on the effect of rotations by comparing experimental and theoretical PECD data for norcamphor, a single-conformer molecule.
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
(2022)
Article
Biochemistry & Molecular Biology
Piero Decleva, Mauro Stener, Daniele Toffoli
Summary: This article provides a detailed description of a multicenter (LCAO) B-spline basis and its capabilities in providing convergent solutions for electronic continuum states and wavepacket propagation. The basis forms the core of the Tiresia code, which accurately and computationally efficiently describes the photoionization properties of complex systems.
Article
Chemistry, Multidisciplinary
Marta Monti, Mauro Stener, Massimiliano Aschi
Summary: The present study introduces a novel computational protocol for modeling the UV-circular dichroism spectra of solvated species. It utilizes quantum-chemical calculations to account for the conformational motion and solvent effects, and has been proven to provide reliable results. Temperature effects are also properly considered, and the method is validated through comparison with experimental data.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2022)
Article
Chemistry, Multidisciplinary
Marco Medves, Giovanna Fronzoni, Mauro Stener
Summary: This article presents a new set of auxiliary basis functions suitable for fitting the induced electron density. The set has been optimized to accurately calculate absorption spectra using the complex polarizability algorithm of time-dependent density functional theory (TDDFT). An automatic procedure has been developed to evaluate the resemblance of the calculated spectra to a reference, allowing for the reduction of the basis set size while maximizing accuracy. This new set of basis functions has already been included in the latest release of the AMS suite of programs, and will greatly improve the applicability range of the polTDDFT method with higher accuracy and less computational effort.
JOURNAL OF COMPUTATIONAL CHEMISTRY
(2022)
Article
Chemistry, Physical
Valeria Lanzilotto, Daniele Toffoli, Elisa Bernes, Mauro Stener, Elisa Viola, Albano Cossaro, Roberto Costantini, Cesare Grazioli, Roberta Totani, Giovanna Fronzoni
Summary: The electronic characterization of cyanuric acid in gas phase and on Au(111) surface with H-bonding has been investigated using XPS and NEXAFS spectroscopy. The combination of experimental and theoretical methods reveals the effect of H-bond formation on the spectra.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Physical
Daniele Toffoli, Matteo Quarin, Giovanna Fronzoni, Mauro Stener
Summary: This benchmark study investigates the vertical excitation energies and oscillator strengths of 17 boron-dipyrromethene (BODIPY) structures with different ring sizes and substituents. The results obtained from time-dependent density functional theory (TDDFT) and delta-self-consistent-field (Delta SCF) methods, using various exchange correlation kernels, are compared with experimental excitation energies. The study shows that the time-independent Delta SCF DFT method, particularly when combined with hybrid PBE0 and B3LYP functionals, outperforms TDDFT and rivals more computationally expensive wave function based methods in terms of accuracy.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Physical
Marco Medves, Daniele Toffoli, Mauro Stener, Luca Sementa, Alessandro Fortunelli
Summary: The study reveals that BODIPY dye can interact with a plasmonic system in a selective way based on the orientation of the fragments, affecting the plasmon resonance. Analysis of induced density shapes and Individual Component Map of the Oscillator Strength provides insight into the coupling mechanism and design of hybrid systems.
JOURNAL OF PHYSICAL CHEMISTRY A
(2022)
Article
Chemistry, Physical
M. Monti, M. Stener, E. Coccia
Summary: In this paper, the authors propose a method for computing the electronic circular dichroism (ECD) spectra of chiral molecules using real-time propagation of the time-dependent Schrodinger equation (TDSE). By coupling TDSE with a given treatment of the electronic structure of the target, the time-dependent induced magnetic moment is used to compute the ECD spectrum from an explicit electric perturbation. The results show that the time-domain ECD spectra accurately reproduce the frequency-domain ones obtained from linear-response theory and agree quantitatively with available experimental data.
JOURNAL OF CHEMICAL PHYSICS
(2023)
Article
Chemistry, Multidisciplinary
Marta Monti, Maria Francisca Matus, Sami Malola, Alessandro Fortunelli, Massimiliano Aschi, Mauro Stener, Hannu Hakkinen
Summary: The water-soluble glutathione-protected [Au-25(GSH)(18)](-1) nanocluster was investigated using molecular dynamics simulations, essential dynamics analysis, and time-dependent density functional theory calculations. Conformational changes, weak interactions, and solvent effects, particularly hydrogen bonds, were found to significantly influence the optical response of the system. The analysis demonstrated the sensitive nature of the electronic circular dichroism to the presence of solvent and the active role of the solvent in forming a chiral solvation shell around the cluster. This work presents a successful strategy for studying chiral interfaces between metal nanoclusters and their environments, with potential applications in chiral electronic interactions with biomolecules.
Article
Chemistry, Physical
M. Monti, G. Brancolini, E. Coccia, D. Toffoli, A. Fortunelli, S. Corni, M. Stener, M. Aschi
Summary: The effects of the conformational dynamics of 2-PET protective ligands on the electronic circular dichroism (ECD) of chiral Au-38(SC2H4Ph)(24) clusters are investigated. ECD spectra are calculated using the first principle polTDDFT approach on a series of conformations extracted from MD simulations, and weighted to predict the final spectrum. The results show the importance of considering conformational effects in ECD modeling of chiral nanoclusters.
JOURNAL OF PHYSICAL CHEMISTRY LETTERS
(2023)
Article
Chemistry, Physical
Pierpaolo D'Antoni, Marco Medves, Daniele Toffoli, Alessandro Fortunelli, Mauro Stener, Lucas Visscher
Summary: The use of the Resolution of Identity technique in TDDFT simulations has shown promising results in accurately and efficiently predicting the photoabsorption spectra of complex species.
JOURNAL OF PHYSICAL CHEMISTRY A
(2023)
Article
Biochemistry & Molecular Biology
Nicola Domenis, Pablo Grobas Illobre, Margherita Marsili, Mauro Stener, Daniele Toffoli, Emanuele Coccia
Summary: In this study, recently developed real-time descriptors are applied to investigate the time evolution of plasmonic features of pentagonal Ag clusters. The method involves the propagation of the time-dependent Schrodinger equation using a singly excited TDDFT ansatz. Transition contribution maps (TCMs) and induced density are used to characterize the optical response of the clusters when interacting with resonant pulses at different energy levels. The results demonstrate a plasmonic response when a longitudinal pulse is applied and a molecular transition when a transverse pulse is employed, which are confirmed by the induced charge distributions.
Article
Chemistry, Multidisciplinary
M. Monti, E. Scarel, A. Hassanali, M. Stener, S. Marchesan
Summary: This study uncovers the conformational differences that drive self-assembly of dipeptides into distinct outcomes. Through in silico and experimental data, the electronic circular dichroism (ECD) spectra of self-assembling dipeptides were analyzed, revealing the importance of folded or extended conformers in the self-assembly process.
CHEMICAL COMMUNICATIONS
(2023)