Theory of electron detachment in collisions of negative ions with atoms II. Survival probability, differential elastic cross section, and total detachment cross section for the H - –He system

1982 ◽  
Vol 379 (1776) ◽  
pp. 209-216 ◽  
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Preceding Paper ◽  
Negative Ions ◽  
Elastic Cross Section ◽  
Negative Ion ◽  
Total Probability ◽  
Electron Detachment ◽  
Close Coupling ◽  
Probability Of Survival

The close-coupling theory of electron detachment, developed in the preceding paper I, is used to calculate the probability of survival of the negative ion, and the total probability of electron detachment. Neglect of a term reduces the formulas to more familiar ones, which are then used to calculate differential elastic cross sections and total detachment cross sections for the H - –He and D - –He systems. Good agreement with experi­mental results is obtained.

Detachment cross sections for sulphur negative ion – rare gas collisions

1987 ◽  
Vol 65 (7) ◽  
pp. 735-738 ◽  
Author(s):  
B. Hird ◽  
M. Bruyère ◽  
S. Fafard
Keyword(s):  
Cross Sections ◽  
Negative Ions ◽  
Negative Ion ◽  
Rare Gas ◽  
Electron Detachment ◽  
Double Electron

The atomic cross sections for single and double electron detachment from sulphur negative ions in single collisions with He, Ne, Ar, Kr, and Xe are determined at collision energies between 12.5 and 110 keV.

Single-electron detachment cross sections of Co− and Ir− in collision with Ar and an empirical formula for single-electron detachment cross sections of negative ions in collision with Ar

2013 ◽  
Vol 91 (2) ◽  
pp. 175-179 ◽  
Author(s):  
Zhixian Geng ◽  
Xue Bai ◽  
Baoren Wei ◽  
Xuemei Zhang
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Electron Affinity ◽  
Least Squares Method ◽  
Negative Ions ◽  
Single Electron ◽  
Clear Correlation ◽  
Physical Parameters ◽  
Electron Detachment ◽  
Empirical Formulas

The single-electron detachment (SED) cross sections for Co− and Ir− in collision with Ar in the energy region of 10–30 keV are obtained in our laboratory. As our previous paper reported, the SED cross sections have velocity and electron affinity dependency. Using the least-squares method, we analyze the available experimental data of SED cross sections for different negative ions in collision with Ar, and get empirical formulas for different sets of anionic projectiles. For most anionic projectiles, there is a clear correlation between increasing electron affinity and decreasing SED cross sections. Co and Ir, however, are an exception, and we discuss how other physical parameters can be taken into account in the search for general scaling rules for SED cross sections. As the incident velocity increases, the cross section dependence of the anion's electron affinity becomes weaker, and the relation between the SED cross sections and νp is supposed to be [Formula: see text].

scholarly journals Fullerene Negative Ions: Formation and Catalysis

2020 ◽  
Author(s):  
Zineb Felfli ◽  
Kelvin Suggs ◽  
Nantambu Nicholas ◽  
Alfred Z. Msezane
Keyword(s):  
Transition State ◽  
Cross Sections ◽  
Water Oxidation ◽  
Regge Pole ◽  
Negative Ions ◽  
Negative Ion ◽  
Total Cross Sections ◽  
Hydrogen Bond Strength ◽  
Low Energy Electron ◽  
Fundamental Mechanism

We first explore negative-ion formation in fullerenes C44, C60, C70, C98, C112, C120, C132 and C136 through low-energy electron elastic scattering total cross sections calculations using our Regge-pole methodology. Water oxidation to peroxide and water synthesis from H2 and O2 are then investigated using the anionic catalysts C44ˉ to C136ˉ. The fundamental mechanism underlying negative-ion catalysis involves hydrogen bond strength-weakening in the transition state. DFT transition state calculations found C60ˉ numerically stable for both water and peroxide synthesis, C100ˉ increases the energy barrier the most and C136ˉ the most effective catalyst in both water synthesis and oxidation to H2O2.

scholarly journals Quantitative Ausmessung des Brom-Affinitätskontinuums und Bestimmung der Detachment-und Attachment-Querschnitte

1970 ◽  
Vol 25 (11) ◽  
pp. 1617-1626 ◽  
Author(s):  
H. Frank ◽  
M. Neiger ◽  
H.-P. Popp
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Electron Affinity ◽  
Elastic Cross Section ◽  
Electron Atom ◽  
Intensity Measurements ◽  
Long Wave ◽  
The Mean ◽  
Intense Electron

Abstract A wall stabilized low-current cylindric arc was used to produce the radiation of the negative Bromine-ions. The radiation consists of an affinity-continuum with a long-wave threshold of 3682 Å, yielding an electron affinity for Bromine of 3.366 eV, and of an intense electron-atom Bremsstrahlung in the visible. Intensity measurements of the continua allow the determination of the photo-detachment-and attachment-cross-sections of Bromine and also the determination of the mean elastic cross-section of electrons against Bromine atoms.

A measurement of the cross section for production of He + (2 S ) ions by electron impact excitation of ground state helium ions

1966 ◽  
Vol 290 (1420) ◽  
pp. 74-93 ◽  
Keyword(s):  
Plane Wave ◽  
Cross Section ◽  
Cross Sections ◽  
Absolute Magnitude ◽  
Impact Excitation ◽  
Electron Impact Excitation ◽  
Close Coupling ◽  
Born Cross Section ◽  
The Absolute ◽  
The Cross

A crossed beams method has been used to measure the cross section for the production of He + (2 S ) by electrons incident upon He + (1 S ) in the energy range from threshold to 750 eV. The cross section was measured in arbitrary units with an accuracy of ± 5 % and at the higher energies its energy dependence is in close agreement with that calculated by means of the plane-wave Born approximation. Consequently the cross section has been normalized to the plane-wave Born cross section at energies between 435 and 750 eV to obtain the absolute magnitude. An independent estimate of the absolute magnitude was made to with in ± 30 % using only the experimental parameters, and the absolute cross sections given by the two methods agree within the experimental uncertainties. The normalized cross section is compared with cross sections given by the close-coupling approximation and various Coulomb-Born approximations. At the lower energies the normalized cross section is considerably smaller than any of the theoretical values, but the measurements are consistent with the existence of a finite cross section at threshold if the energy spread of the electron beam is taken in to account.

scholarly journals Role of Negative Ion Resonances in Electron Scattering from Atoms and Molecules

1999 ◽  
Vol 52 (3) ◽  
pp. 473 ◽  
Author(s):  
S. J. Buckman ◽  
D. T. Alle ◽  
M. J. Brennan ◽  
P. D. Burrow ◽  
J. C. Gibson ◽  
...  
Keyword(s):  
Electron Scattering ◽  
Cross Sections ◽  
Negative Ions ◽  
Negative Ion ◽  
Electron Correlations ◽  
Molecular Systems ◽  
Atoms And Molecules ◽  
Wide Range ◽  
Scattering Cross Sections

Transient negative ions (resonances) formed during the collision of an electron with an atom or molecule have been extensively studied for over thirty years. The continued interest in these states, both experimentally and theoretically, stems from the profound effects that they can have on electron scattering cross sections and the role that electron–electron correlations play in their formation and quasi-stability. A selective discussion of examples of such resonances, involving one, two and three excited electrons is given for a wide range of atomic and molecular systems.

Single-Electron Detachment Cross Sections for Transition-Element Negative Ions Ti   , Cr   , Cu   in Collision with N 2

2004 ◽  
Vol 21 (8) ◽  
pp. 1512-1514 ◽  
Author(s):  
Huang Yong-Yi ◽  
Zhang Xue-Mei ◽  
Wu Shi-Min ◽  
Li Guang-Wu ◽  
Lu Fu-Quan
Keyword(s):  
Cross Sections ◽  
Transition Element ◽  
Negative Ions ◽  
Single Electron ◽  
Electron Detachment

Positive ion production in single collisions of Cl− with rare gas atoms

1984 ◽  
Vol 62 (6) ◽  
pp. 544-547 ◽  
Author(s):  
B. Hird ◽  
F. Rahman
Keyword(s):  
Cross Section ◽  
Cross Sections ◽  
Rare Gas ◽  
Electron Detachment ◽  
Centre Of Mass ◽  
Target Mass ◽  
Double Electron ◽  
Ion Production ◽  
Rare Gas Atoms ◽  
Positive Ion

The cross section σ−+ for double electron detachment from Cl− in a single collision with a rare gas atom has been measured between 12.5 and 122.5 keV. The magnitude of these cross sections shows that there is a good probability that a second electron will be emitted in collisions that detach one electron, particularly with light targets. The centre-of-mass cross section decreases with increasing target mass, but the variation is less than that for F− and O− double electron detachment cross sections.

Sign in / Sign up

Export Citation Format

Share Document