AI Article Synopsis
Article Abstract
Neutralization probabilities are presented for hyperthermal energy Na+ ions scattered from a Cu(001) crystal as a function of surface temperature and scattered velocity. A large enhancement in neutralization is observed as the temperature is increased. Velocity-dependent charge transfer regimes are probed by varying the incident energy, with the most prominent surface temperature effects occurring at the lowest energies. The data agree well with results obtained from a model based on the Newns-Anderson Hamiltonian, where the effects of both temperature and velocity are incorporated.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1103/PhysRevLett.90.013201 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
A Preliminary Investigation of Thermally Stable Schiff Base Metal Complexes for Hyperthermia: Synthesis and Biological Evaluation.
Antioxidants (Basel)
December 2024
Dhanvanthri Laboratory, Department of Chemistry, Amrita School of Physical Sciences, Amrita Vishwa Vidyapeetham, Coimbatore 641112, India.
A novel Schiff base ligand (L), bearing NO donor sites, was derived from the condensation of 5-chloromethylisophthaldehyde and phenylpropanolamine (PPA). Mononuclear Co(II), Cu(II), and Zn(II) complexes were synthesized and were characterized by FTIR, UV-Vis, H NMR, ESI-mass spectroscopy, molar conductance, and thermal and electrochemical studies. The thermal investigation revealed that the complexes were stable up to 150-250 °C and began to degrade in stages, resulting in the development of respective metal oxides.
View Article and Find Full Text PDFRoom Temperature Hydrogen Atom Scattering Experiments Are Not a Sufficient Benchmark to Validate Electronic Friction Theory.
J Phys Chem Lett
December 2024
Department of Chemistry, University of Warwick, Gibbet Hill Road, CV4 7AL Coventry, U.K.
In the dynamics of atoms and molecules at metal surfaces, electron-hole pair excitations can play a crucial role. In the case of hyperthermal hydrogen atom scattering, they lead to nonadiabatic energy loss and highly inelastic scattering. Molecular dynamics with electronic friction simulation results, based on an isotropic homogeneous electron gas approximation, have previously aligned well with measured kinetic energy loss distributions, indicating that this level of theoretical description is sufficient to describe nonadiabatic effects during scattering.
View Article and Find Full Text PDFMechanistic Insights into Nonadiabatic Interband Transitions on a Semiconductor Surface Induced by Hydrogen Atom Collisions.
JACS Au
November 2024
Key Laboratory of Precision and Intelligent Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
To understand the recently observed enigmatic nonadiabatic energy transfer for hyperthermal H atom scattering from a semiconductor surface, Ge(111)(2 × 8), we present a mixed quantum-classical nonadiabatic molecular dynamics model based on the time-dependent evolution of Kohn-Sham orbitals and a classical path approximation. Our results suggest that facile nonadiabatic electronic transitions from the valence band to the conduction band occur selectively at the rest atom site, where surface states are doubly occupied, but not at the adatom site, where empty surface states are localized. This drastic site specificity can be attributed to the changes of the local band structure upon energetic H collisions at different surface sites, leading to transient near degeneracies and significant couplings between occupied and unoccupied orbitals at the rest atom but not at the adatom.
View Article and Find Full Text PDFMethanol Formation in Hyperthermal Oxygen Collisions with Methane Clathrate Ice.
J Phys Chem A
November 2024
Materials and Process Simulation Center, California Institute of Technology, Pasadena, California 91125, United States.
Article Synopsis
- - The study investigates how hyperthermal reactive ions, specifically water group molecules, affect the organic chemistry of icy bodies, which could be important for understanding prebiotic conditions.
- - Molecular dynamics simulations reveal that irradiating carbon-bearing ice with atomic oxygen primarily produces methanol, suggesting a unique hot-atom reaction mechanism, especially at lower doses.
- - At higher irradiation doses, the chemical composition shifts towards more oxidized carbon compounds, with formaldehyde becoming more prevalent than methanol, indicating varying effects of different impactors and guest species on the ice chemistry.
Theoretical Investigation of Rate Coefficients and Dynamical Mechanisms for N + N + N Three-Body Recombination Based on Full-Dimensional Potential Energy Surfaces.
Molecules
October 2024
Institute of Theoretical and Computational Chemistry, Key Laboratory of Mesoscopic Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Three-body recombination reactions, in which two particles form a bound state while a third one bounces off after the collision, play significant roles in many fields, such as cold and ultracold chemistry, astrochemistry, atmospheric physics, and plasma physics. In this work, the dynamics of the recombination reaction for the N system over a wide temperature range (5000-20,000 K) are investigated in detail using the quasi-classical trajectory (QCT) method based on recently developed full-dimensional potential energy surfaces. The recombination products are N() + N() in the 1″ state, N() + N() in the 2″ state, and N() + N() in both the 1″ and 2″ states.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!