The ground and excited state nonvalence correlation-bound (NVCB) anion states of the hexagonal polycylic aromatic hydrocarbons and of hexagonal graphene nanoflakes are characterized using a one-electron model Hamiltonian which incorporates atomic electrostatic moments up to the quadrupole, coupled inducible charges and dipoles, and atom-centered Gaussians to describe the short-range repulsive interactions. Extrapolation of the calculated electron binding energies of the lowest energy symmetric and antisymmetric (with respect to the molecular plane) NVCB anions of both the polycylic aromatic hydrocarbons and the carbon nanoflakes to the → ∞ limit yields binding energies that are in good agreement with those of the most stable symmetric and antisymmetric image potential states of freestanding graphene as determined from two-photon photoemission spectroscopy (2PPE) experiments.
Download full-text PDF |
Source |
|---|---|
| http://www.ncbi.nlm.nih.gov/pmc/articles/PMC11194819 | PMC |
| http://dx.doi.org/10.1021/acs.jpclett.4c01308 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Demonstrating the Connection between the Nonvalence Correlation-Bound Anions of Polyaromatic Hydrocarbons and the Image Potential States of Graphene Using a One-Electron Model Hamiltonian.
J Phys Chem Lett
June 2024
Department of Chemistry, University of Pittsburgh, 219 Parkman Avenue, Pittsburgh, Pennsylvania 15260, United States.
The ground and excited state nonvalence correlation-bound (NVCB) anion states of the hexagonal polycylic aromatic hydrocarbons and of hexagonal graphene nanoflakes are characterized using a one-electron model Hamiltonian which incorporates atomic electrostatic moments up to the quadrupole, coupled inducible charges and dipoles, and atom-centered Gaussians to describe the short-range repulsive interactions. Extrapolation of the calculated electron binding energies of the lowest energy symmetric and antisymmetric (with respect to the molecular plane) NVCB anions of both the polycylic aromatic hydrocarbons and the carbon nanoflakes to the → ∞ limit yields binding energies that are in good agreement with those of the most stable symmetric and antisymmetric image potential states of freestanding graphene as determined from two-photon photoemission spectroscopy (2PPE) experiments.
View Article and Find Full Text PDFOn the performance of second-order approximate coupled-cluster singles and doubles methods for non-valence anions.
Phys Chem Chem Phys
January 2024
Department of Chemistry, KU Leuven, Celestijnenlaan 200F, B-3001 Leuven, Belgium.
We investigate the capability of several variants of the second-order approximate coupled-cluster singles and doubles (CC2) method to describe dipole-bound, quadrupole-bound, and correlation-bound molecular anions. The binding energy of anions formed by electron attachment to closed-shell molecules is computed using the electron attachment variant of CC2 (EA-CC2), whereas anions with a closed-shell ground state are treated with the standard CC2 method that preserves the number of particles. We find that EA-CC2 captures the binding energies of dipole-bound radical anions quite well, whereas results for other types of non-valence anions are less reliable.
View Article and Find Full Text PDFState-Specific Chemical Dynamics of the Nonvalence Bound State of the Molecular Anions.
Acc Chem Res
October 2022
Department of Chemistry, KAIST, Daejeon34141, Republic of Korea.
Article Synopsis
- Nonvalence bound states (NBS) are loosely connected anionic states where an excess electron weakly interacts with a neutral core, differing from typical valence orbitals that directly impact molecular structure and reactivity.
- NBS can be categorized into three types (dipole-bound, quadruple-bound, and correlation-bound states) based on how the electron interacts with the neutral particle, and they play significant roles in various chemical contexts, such as atmospheric and biological chemistry.
- Recent studies utilized advanced spectroscopy techniques to explore NBS dynamics, revealing details like how the autodetachment rate varies based on specific vibrational states and the need for more complex theoretical models for better understanding.
Non-Valence Anions of Pyridine and the Diazines.
J Phys Chem A
August 2022
Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15218, United States.
The dipole-bound anions of pyridine, pyridazine, and pyrimidine are characterized using equation of motion coupled cluster singles and doubles calculations. These calculations predict that the anions of pyridine, pyrimidine and pyridazine are bound in the Born-Oppenheimer approximation by 0.05, 0.
View Article and Find Full Text PDFThe role of high-order electron correlation effects in a model system for non-valence correlation-bound anions.
J Chem Phys
December 2020
Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania 15260, USA.
The diffusion Monte Carlo (DMC), auxiliary field quantum Monte Carlo (AFQMC), and equation-of-motion coupled cluster (EOM-CC) methods are used to calculate the electron binding energy (EBE) of the non-valence anion state of a model (HO) cluster. Two geometries are considered, one at which the anion is unbound and the other at which it is bound in the Hartree-Fock (HF) approximation. It is demonstrated that DMC calculations can recover from the use of a HF trial wave function that has collapsed onto a discretized continuum solution, although larger EBEs are obtained when using a trial wave function for the anion that provides a more realistic description of the charge distribution and, hence, of the nodal surface.
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!