Related papers: Coulomb Pairing and Double Photoionization in Arom…
Recently reported anomalies in the double-photonionization spectra of aromatic molecules such as benzene, naphthalene, anthracene and coronene are attributed to Coulomb-pair resonances of pi electrons.
We present an analysis of the pairing resonances observed in photo-double-ionization studies of CnHm aromatic molecules with multiple benzene-like rings. The analysis, which is based on the Coulomb pairing model, is applied to naphthalene,…
It is shown that the M$^{2+}$ ion yield in the double photoionization of the aromatic hydrocarbons, pyrene and coronene, can be expressed as a superposition of a contribution from a resonance involving carbon atoms on the perimeter and…
The low energy resonance in the double photoionization of the aromatic hydrocarbons pyrene (C$_{16}$H$_{10}$) and coronene (C$_{24}$H$_{12}$) is investigated theoretically using an approach based on the one-dimension Hubbard model for…
We investigate the linear behavior in the 2+ ion concentration observed in the double photoionization of a variety of aromatic molecules. We show it arises when the photoelectrons are emitted simultaneously. Neglecting the momentum of the…
We present numerical studies of one- and two-photon excited states ordering in a number of polycyclic aromatic hydrocarbon molecules: coronene, hexa-peri-hexabenzocoronene and circumcoronene, all possessing $D_{6h}$ point group symmetry…
Strong electron correlation effects in the photophysics of quasi-one-dimensional $\pi$-conjugated organic systems such as polyenes, polyacetylenes, polydiacetylenes, etc., have been extensively studied. Far less is known on correlation…
The role of the nucleon resonances in the double polarization observables of pion photoproduction is investigated by using the resonance parameters predicted by Capstick and Roberts. As an example, we show that the not-well-determined…
A well-known property of aromatic molecules is their highly anisotropic response to the presence of an external magnetic field: the component of their magnetic susceptibility parallel to the field is generally much larger than the remaining…
Thermoelectric properties of a two-level molecule attached to the metallic electrodes are analyzed using the equation of motion technique within the Green function formalism. Results show that the electrical conductance is strongly…
The coupling between a two-level system and its environment leads to decoherence. Within the context of coherent manipulation of electronic or quasiparticle states in nanostructures, it is crucial to understand the sources of decoherence.…
The electronic and optical properties of various polycyclic aromatic hydrocarbons (PAHs) with lower symmetry, namely, benzo[ghi]perylene (C$_{22}$H$_{12}$), benzo[a]coronene (C$_{28}$H$_{14}$), naphtho[2,3a]coronene (C$_{32}$H$_{16}$),…
The so-called aromatic infrared bands are attributed to emission of polycyclic aromatic hydrocarbons. The observed variations toward different regions in space are believed to be caused by contributions of different classes of PAH…
We show that the second-order, two-time correlation functions for phonons and photons emitted from a vibronic molecule in a thermal bath result in bunching and anti-bunching (a purely quantum effect), respectively. Signatures relating to…
We calculate the pi-/pi+ ratio for Pb+Pb at CERN/SPS energies and for Au+Au at BNL/AGS energies using a (3+1) dimensional hydrodynamical model. Without consideration of Coulomb effect an enhancement of this ratio at low mt is found…
The electronic and optical properties of polycyclic aromatic hydrocarbons (PAHs) present a strong dependence on their size and geometry. We tackle this issue by analyzing the spectral features of two prototypical classes of PAHs, belonging…
Resonant two-photon ionization in a system consisting of two spatially well-separated atoms is studied. Due to two-center electron-electron correlations, the ionization may also proceed through photo-excitation of both atoms with subsequent…
The angular and polarization properties of the photon pair emitted in the two--photon decay of $2s$ hyperfine states in hydrogenlike ions are investigated within the relativistic Dirac framework and second order perturbation theory. The…
The resonant spectra of hydrogen and anti-hydrogen atoms in the presence of an external electric field are compared theoretically. It is shown that nonresonant corrections to the transition frequency contain terms linear in the electric…
We investigate the interaction between the electrons of a two-dimensional metal and the acoustic phonons of an underlying piezoelectric substrate. Fundamental inequalities can be obtained from general energy arguments. As a result, phonon…