Inelastic Scattering of High Energy Electrons by Helium

1973 ◽  
Vol 51 (3) ◽  
pp. 311-315 ◽  
Author(s):  
S. P. Ojha ◽  
P. Tiwari ◽  
D. K. Rai
Keyword(s):  
Ground State ◽  
High Energy ◽  
Wave Functions ◽  
Oscillator Strengths ◽  
Final States ◽  
Interaction Type ◽  
Hartree Fock ◽  
High Energy Electrons ◽  
Approximate Wave ◽  
Accurate Wave

Generalized oscillator strengths and the cross section for excitation of helium by electron impact have been calculated in the Born approximation. Transitions from the ground state to the n1P (n = 2 and 3) states have been considered. Highly accurate wave functions of the Hartree–Fock and "configuration–interaction" type have been used to represent the ground state. Approximate wave functions due to Messmer have been employed for the final states. The results are compared with other calculations and with experiment.

Born Cross Sections for the Excitation of Helium by Fast Protons

1972 ◽  
Vol 50 (19) ◽  
pp. 2253-2256 ◽  
Author(s):  
S. P. Ojha ◽  
P. Tiwari ◽  
D. K. Rai
Keyword(s):  
Cross Sections ◽  
Ground State ◽  
Born Approximation ◽  
Wave Functions ◽  
Final States ◽  
Interaction Type ◽  
Hartree Fock ◽  
Approximate Wave ◽  
Fast Protons ◽  
Accurate Wave

Cross sections for excitation of helium by proton impact have been calculated in the Born approximation. Transitions from the ground state to the n1P(n = 2 and 3) states have been considered. Highly accurate wave functions of the Hartree–Fock and configuration-interaction type have been used to represent the ground state. Approximate wave functions due to Messmer have been employed for the final states. The results are compared with other calculations and with experiments.

Approximate Wave Functions for High Energy Electrons in Coulomb Fields

1934 ◽  
Vol 46 (5) ◽  
pp. 391-396 ◽  
Author(s):  
W. H. Furry
Keyword(s):  
High Energy ◽  
Wave Functions ◽  
High Energy Electrons ◽  
Approximate Wave

Towards accurate wave functions and oscillator strengths

2000 ◽  
Author(s):  
Alan Hibbert
Keyword(s):  
Wave Functions ◽  
Oscillator Strengths ◽  
Accurate Wave

Hartree–Fock calculation for the electronic structure of H+3 using numerically optimized orbitals

2001 ◽  
Vol 79 (2-3) ◽  
pp. 673-679
Author(s):  
J D Talman
Keyword(s):  
Electronic Structure ◽  
Ground State ◽  
Equilateral Triangle ◽  
Wave Functions ◽  
Equilibrium Geometry ◽  
Molecular Ion ◽  
Interatomic Spacing ◽  
Hartree Fock ◽  
Gaussian Orbitals

The Hartree–Fock wave functions for the ground state of the H2 molecule and the H+3 molecular ion are computed using radial orbitals that are numerically optimized. It is shown that these orbitals yield results comparable in accuracy to those obtained using much larger bases of Gaussian orbitals. As in previous calculations, the equilibrium geometry for H+3 is found to be that of an equilateral triangle, with an interatomic spacing of 1.64a0. PACS No.: 13.15+q

Electric Quadrupole Transitions in Na I, Mg II and Al III

1972 ◽  
Vol 50 (11) ◽  
pp. 1169-1174 ◽  
Author(s):  
C. E. Tull ◽  
M. Jackson ◽  
R. P. McEachran ◽  
M. Cohen
Keyword(s):  
Electric Quadrupole ◽  
Wave Functions ◽  
Oscillator Strengths ◽  
Hartree Fock ◽  
Good Agreement

Theoretical multiplet strengths for electric quadrupole transitions between 2S, 2P0, 2D, and 2F0 levels of Na I, Mg II, and Al III have been calculated using Hartree–Fock wave functions of frozen-core type. The resulting 2S–2D oscillator strengths for Na I are in good agreement with calculations by Bogaard and Orr, Boyle and Murray, and Warner; however, for Mg II there is a discrepancy of a factor of 2 between our results and those of Warner.

Cancellation in the transition integrals for some dipole transitions: He isoelectronic series

1980 ◽  
Vol 58 (4) ◽  
pp. 546-548 ◽  
Author(s):  
Swadesh Kumar Ghoshal ◽  
Sankar Sengupta
Keyword(s):  
Confidence Level ◽  
Wave Functions ◽  
Oscillator Strengths ◽  
Isoelectronic Sequence ◽  
Hartree Fock ◽  
Isoelectronic Series

The amount of cancellation in the transition integrals for some np–n′d and nd–n′f singlet and triplet transitions for some members of helium isoelectronic sequence is estimated with Hartree–Fock wave functions. The results may act as a measure of the confidence level that can be attributed to the values of oscillator strengths of the respective cases.

Relativistic oscillator strengths for np2 → np(n + 1)s transition array of SnI and PbI spectra in jj and intermediate coupling

1979 ◽  
Vol 57 (2) ◽  
pp. 147-151 ◽  
Author(s):  
J. Migdałek
Keyword(s):  
Transition Probabilities ◽  
Theoretical Data ◽  
Wave Functions ◽  
Oscillator Strengths ◽  
Intermediate Coupling ◽  
Hartree Fock ◽  
Semiempirical Approach ◽  
Exchange Effects ◽  
Relativistic Oscillator ◽  
Transition Array

The relativistic oscillator strengths for the np2 → np(n + 1)s transition array as well as the lifetimes of levels of the np(n + 1)s configuration in SnI and PbI spectra were calculated in jj and intermediate coupling. The relativistic radial integrals were computed employing the wave functions obtained by a semiempirical approach which allowed for exchange effects. The results obtained are compared with existing experimental and theoretical data. The significance of intermediate coupling for oscillator strengths computations is discussed. The agreement with experiment is for the present semiempirical results generally better (particularly for the PbI spectrum) than for oscillator strength deduced from 'Optimized Hartree–Fock–Slater' transition probabilities, which were published previously.

Electronic wave functions II. A calculation for the ground state of the beryllium atom

1950 ◽  
Vol 201 (1064) ◽  
pp. 125-137 ◽  
Keyword(s):  
Wave Function ◽  
Variational Method ◽  
Ground State ◽  
Accurate Result ◽  
Energy Criterion ◽  
Wave Functions ◽  
Exponential Functions ◽  
Approximate Wave Function ◽  
Electronic Wave Functions ◽  
Approximate Wave

An approximate wave function expressed in terms of exponential functions, spherical harmonics, etc., with numerical coefficients has been calculated for the ground state of the beryllium atom . Judged by the energy criterion this gives a more accurate result than the Hartree result which was the best previously known. This has been calculated as a trial of a fresh method of calculating atomic wave functions. A linear combination of Slater determinants is treated by the variational method. The results suggest that this will provide a more powerful and convenient method than has previously been available for atoms with more than two electrons.

Coherent X-ray Scattering Factors for Various Configurations of Lanthanides and Their Positive Ions

1975 ◽  
Vol 53 (1) ◽  
pp. 93-96 ◽  
Author(s):  
Robert Benesch ◽  
K. M. S. Saxena
Keyword(s):  
Ground State ◽  
Wave Functions ◽  
X Ray ◽  
Hartree Fock ◽  
Positive Ions ◽  
X Ray Scattering ◽  
Scattering Factor ◽  
Ray Scattering

Coherent X-ray scattering factors have been computed from numerical Hartree–Fock wave functions for the neutral lanthanides and for their single-, double-, and triple-positive ions having the most commonly occurring 6sm4fn ground state configurations. For small scattering angles, the scattering factors for the ions vary among the various configurations. At large scattering angles all configurations for a given ion yield similar values for the scattering factor.

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