Effect of molecular constitution and conformation on positron binding and annihilation in alkanes.
@article{Swann2020EffectOM, title={Effect of molecular constitution and conformation on positron binding and annihilation in alkanes.}, author={A R Swann and Gleb Gribakin}, journal={The Journal of chemical physics}, year={2020}, volume={153 18}, pages={ 184311 } }
The model-potential approach previously developed by the authors to study positron interactions with molecules is used to calculate the positron binding energy for n-alkanes (CnH2n+2) and the corresponding cycloalkanes (CnH2n). For n-alkanes, the dependence of the binding energy on the conformation of the molecule is investigated, with more compact structures showing greater binding energies. As a result, thermally averaged binding energies for larger alkanes (n ≳ 9) show a strong temperature…
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References
SHOWING 1-10 OF 58 REFERENCES
Dependence of positron–molecule binding energies on molecular properties
- Chemistry, Physics
- 2009
Positron annihilation on many molecular species occurs via capture into vibrational Feshbach resonances. The study of the downshifts in the energy of these resonances from the vibrational modes in…
Interplay between permanent dipole moments and polarizability in positron-molecule binding
- Physics, Chemistry
- 2012
Energy-resolved studies of positron-molecule collisions exhibit vibrational Feshbach resonances in annihilation, thus providing evidence that positrons can bind to these species. The downshifts of…
Calculations of positron binding and annihilation in polyatomic molecules.
- Physics, ChemistryThe Journal of chemical physics
- 2018
A model-potential approach to calculating positron-molecule binding energies and annihilation rates is developed and can be applied to both strongly polar and weakly polar or nonpolar systems.
Positron Binding and Annihilation in Alkane Molecules.
- Physics, ChemistryPhysical review letters
- 2019
A model-potential approach has been developed to study positron interactions with molecules, including rings and isomers, and the calculated binding energies and annihilation rates are in good agreement with experimental data.
Positron binding to hydrocarbon molecules: calculation using the positron–electron correlation polarization potential
- Physics, ChemistryThe European Physical Journal D
- 2019
Abstract
Positron binding energies of naphthalene and alkanes (CnH2n+2 with n = 3 − 16) are calculated using the correlation polarization potential approach, where the short-range positron–electron…
Effect of positron–atom interactions on the annihilation gamma spectra of molecules
- Physics, Chemistry
- 2012
Calculations of γ-spectra for positron annihilation on a selection of molecules, including methane and its fluoro-substitutes, ethane, propane, butane and benzene are presented. The annihilation…
Feshbach-resonance-mediated annihilation in positron interactions with large molecules
- Physics, Chemistry
- 2008
Measurements of positron-on-molecule annihilation have established that positrons attach to a variety of molecules via vibrational Feshbach resonances VFRs. These resonances, in turn, result in…
Role of binding energy in Feshbach-resonant positron-molecule annihilation.
- Physics, ChemistryPhysical review letters
- 2007
Measurements of positron-on-molecule annihilation have established that positrons bind to a variety of molecules via vibrational Feshbach resonances, and annihilation rates for a broad class of molecules lie on a universal curve as a function of the number of molecular vibrational degrees of freedom.
Positron-molecule interactions: Resonant attachment, annihilation, and bound states
- Physics, Chemistry
- 2010
This article presents an overview of current understanding of the interaction of low-energy positrons with molecules with emphasis on resonances, positron attachment, and annihilation. Measurements…
Feshbach-resonance-mediated positron annihilation in small molecules
- Physics
- 2008
Large positron annihilation cross sections have been observed for a variety of molecules at various energies below the threshold for positronium formation. These large values are due to vibrational…