Symmetry Breaking in the Lowest-Lying Excited-State of CCl: Valence Shell Spectroscopy in the 5.0-10.8 eV Photon Energy Range.

We report absolute high-resolution vacuum ultraviolet (VUV) photoabsorption cross-sections of carbon tetrachloride (CCl) in the photon energy range 5.0-10.8 eV (248-115 nm).

Low-Energy Positron Scattering by Pyridine and Aniline.

Calculated differential and integral cross sections for elastic scattering of low-energy positrons by pyridine and aniline are presented here. The cross sections were obtained using the Schwinger multichannel method in the static-plus polarization approximation, and the Born closure procedure was employed to account for the long-range potential due to the permanent dipole moment of the molecule. The elastic integral cross sections are compared with available theoretical and experimental data for the same molecules finding an overall good agreement.

A Complete Cross Section Data Set for Electron Scattering by Pyridine: Modelling Electron Transport in the Energy Range 0-100 eV.

Electron scattering cross sections for pyridine in the energy range 0-100 eV, which we previously measured or calculated, have been critically compiled and complemented here with new measurements of electron energy loss spectra and double differential ionization cross sections. Experimental techniques employed in this study include a linear transmission apparatus and a reaction microscope system. To fulfill the transport model requirements, theoretical data have been recalculated within our independent atom model with screening corrected additivity rule and interference effects (IAM-SCAR) method for energies above 10 eV.

Elastic collisions of low-energy positrons with tetrahydrofuran.

We report a study on the scattering of low-energy positrons by the biological relevant molecule tetrahydrofuran. The present calculated integral and differential cross sections were obtained with the Schwinger multichannel method in the static plus polarization approximation. The Born closure procedure was employed to account for the long range potential due to the permanent dipole moment of the molecule.

Low-energy electron collisions with proline and pyrrolidine: A comparative study.

We present a comparative study on the calculated cross sections obtained for the elastic collisions of low-energy electrons with the amino acid proline (CHNO) and its building block pyrrolidine (CHN). We employed the Schwinger multichannel method implemented with pseudopotentials to compute integral, differential, and momentum transfer cross sections in the static-exchange plus polarization approximation, for energies up to 15 eV. We report three shape resonances for proline at around 1.

Shape resonances, virtual state, and Ramsauer-Townsend minimum in the low-energy electron collisions with benzene.

In this work, we revisit the low-energy electron scattering by benzene. We employed the Schwinger multichannel method implemented with pseudopotentials to carry out systematic cross section calculations with different schemes of polarization for the resonant and the totally symmetric irreducible representations within the D symmetry group. We present integral and differential cross sections for incident electron energies up to 12 eV and discuss the shape resonances and the presence of a Ramsauer-Townsend minimum and a virtual state in the former.

Theoretical and experimental study on electron interactions with chlorobenzene: Shape resonances and differential cross sections.

In this work, we report theoretical and experimental cross sections for elastic scattering of electrons by chlorobenzene (ClB). The theoretical integral and differential cross sections (DCSs) were obtained with the Schwinger multichannel method implemented with pseudopotentials (SMCPP) and the independent atom method with screening corrected additivity rule (IAM-SCAR). The calculations with the SMCPP method were done in the static-exchange (SE) approximation, for energies above 12 eV, and in the static-exchange plus polarization approximation, for energies up to 12 eV.

Low-energy positron scattering by pyrimidine.

This work reports elastic integral and differential cross sections for positron collisions with pyrimidine, for energies up to 20 eV. The cross sections were computed with the Schwinger multichannel method in the static plus polarization approximation. We also employed the Born closure procedure to account for the long range potential due to the permanent dipole moment of the molecule.

Collisions of low-energy electrons with cyclohexane.

We report calculated cross sections for elastic scattering of low-energy electrons by cyclohexane (c-C6H12). We employed the Schwinger multichannel method implemented with norm-conserving pseudopotentials in the static-exchange and static-exchange plus polarization approximations, for impact energies up to 30 eV. We compare our calculated integral cross section with experimental total cross sections available in the literature.

Elastic scattering of low-energy electrons by 1,4-dioxane.

We report calculated cross sections for elastic collisions of low-energy-electrons with 1,4-dioxane. Our calculations employed the Schwinger multichannel method with pseudopotentials and were carried out in the static-exchange and static-exchange plus polarization approximations for energies up to 30 eV. Our results show the presence of three shape resonances belonging to the Bu, Au, and Bg symmetries and located at 7.

Shape resonances in low-energy-electron collisions with halopyrimidines.

We report calculated cross sections for elastic collisions of low-energy electrons with halopyrimidines, namely, 2-chloro, 2-bromo, and 5-bromopyrimidine. We employed the Schwinger multichannel method with pseudopotentials to compute the cross sections in the static-exchange and static-exchange plus polarization levels of approximation for energies up to 10 eV. We found four shape resonances for each molecule: three of π* nature localized on the ring and one of σ* nature localized along the carbon-halogen bond.