Intermolecular Potentials from Differential Cross Sections: Ar + Ar

The angular distribution of Ar + Ar scattering at E = 9.16 × 10−14 erg was measured out to the rainbow pattern (supernumerary rainbow and part of the rainbow peak) by the crossed molecular beam technique, with mass spectrometric detection. This distribution was compared to calculated differential cross sections. Total cross sections, and spectroscopic constants for Ar2 were also calculated. The trial potentials were L.J.-12,6, LJ.-20,6, a modified Lennard–Jones potential (L.J.-14,12,8,6) and the Bobetic–Barker potential. The Bobetic–Barker potential is the one most consistent with cross section and spectroscopic experiments.

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Intermolecular potentials by the inversion of molecular beam scattering data. IV. Differential cross sections and potential for LiHg

The Journal of Chemical Physics ◽

10.1063/1.1681004 ◽

1974 ◽

Vol 60 (12) ◽

pp. 4925-4929 ◽

Cited By ~ 32

Author(s):

U. Buck ◽

H. O. Hoppe ◽

F. Huisken ◽

H. Pauly

Keyword(s):

Cross Sections ◽

Differential Cross ◽

Molecular Beam ◽

Scattering Data ◽

Differential Cross Sections ◽

Intermolecular Potentials ◽

Molecular Beam Scattering ◽

Beam Scattering

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Streuung von Ionen I. Regenbogeneffekt bei der elastischen Streuung von Protonen an Argon

Zeitschrift für Naturforschung A ◽

10.1515/zna-1971-0703 ◽

1971 ◽

Vol 26 (7) ◽

pp. 1112-1121

Author(s):

H.-U. Mittmann ◽

H.-P. Weise ◽

A. Ding ◽

A. Henglein

Keyword(s):

Fine Structure ◽

Cross Sections ◽

Differential Cross ◽

Scattering Data ◽

Equilibrium Distance ◽

Jones Potential ◽

Lennard Jones ◽

Fitting Procedure ◽

Potential Depth ◽

Good Agreement

A crossed beam apparatus for scattering experiments with ions on atoms or molecules is described. The results for the elastic scattering of H+ on Ar are reported. Both the structure of the secondary rainbows and the superimposed fine structure were resolved. In order to fit the experimental curves, differential cross sections were calculated in WKB approximation using the following reduced potentials: n, m, g1, g2 , g3 , L, G1 and G2 are form parameters for adjusting the width of the potential well. The fitting procedure and the influence of the chosen potentials on the resulting potential depth E and the equilibrium distance rm are described. Further, the information which can generally be obtained from the observed rainbows and the superimposed fine structure are discussed. No combination of n, m, rm and ε yielded a differential cross section in agreement with the experiments, if the Lennard-Jones potential ULJ or the modifications of Mason and Vanderslice or Schlier and coworkers are used, but excellent agreement can be obtained with the above expressions for U1 and U2 using suitable parameters. For the system H+-Ar we obtain ε = (4.04+0.1) eV, rm = (1.31±0.07) Å. These values are in good agreement with recent ab-initio calculations of Roach and Kuntz. They are considerably different from those obtained by Champion et al. 8, who did not observe the fine structure and used a too narrow potential in the evaluation of the scattering data.

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The Cl + O3 reaction: a detailed QCT simulation of molecular beam experiments

Physical Chemistry Chemical Physics ◽

10.1039/c5cp04323a ◽

2015 ◽

Vol 17 (38) ◽

pp. 25471-25482 ◽

Cited By ~ 3

Author(s):

M. Menéndez ◽

J. F. Castillo ◽

B. Martínez-Haya ◽

F. J. Aoiz

Keyword(s):

Cross Sections ◽

Differential Cross ◽

Molecular Beam ◽

Differential Cross Sections

QCT calculations have been carried out to determine angle–velocity differential cross-sections to simulate the results of molecular beam experiments.

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Deconvolution of Overlapping Features in Electron Energy-loss Spectra: Determination of Absolute Differential Cross Sections for Electron-impact Excitation of Electronic States of Molecules

Australian Journal of Physics ◽

10.1071/p96060 ◽

1997 ◽

Vol 50 (3) ◽

pp. 525 ◽

Cited By ~ 23

Author(s):

L. Campbell ◽

P. J. O. Teubner ◽

M. J. Brunger ◽

B. Mojarrabi ◽

D. C. Cartwright

Keyword(s):

Energy Loss ◽

Electron Energy ◽

Cross Sections ◽

Differential Cross ◽

Electronic States ◽

Impact Excitation ◽

Spectroscopic Constants ◽

Differential Cross Sections ◽

Electron Energy Loss ◽

Electron Energy Loss Spectra

A set of three computer programs is reported which allow for the deconvolution of overlapping molecular electronic state structure in electron energy-loss spectra, even in highly perturbed systems. This procedure enables extraction of absolute differential cross sections for electron-impact excitation of electronic states of diatomic molecules from electron energy-loss spectra. The first code in the sequence uses the Rydberg–Klein–Rees procedure to generate potential energy curves from spectroscopic constants, and the second calculates Franck–Condon factors by numerical solution of the Schrödinger equation, given the potential energy curves. The third, given these Franck–Condon factors, the previously calculated relevant energies for the vibrational levels of the respective electronic states (relative to the v″ = 0 level of the ground electronic state) and the experimental energy-loss spectra, extracts the differential cross sections for each state. Each program can be run independently, or the three can run in sequence to determine these cross sections from the spectroscopic constants and the experimental energy-loss spectra. The application of these programs to the specific case of electron scattering from nitric oxide (NO) is demonstrated.

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