Hartree–Fock Ionization Potentials of Atoms

1973 ◽  
Vol 51 (19) ◽  
pp. 2063-2074 ◽  
Author(s):  
S. Fraga ◽  
K. M. S. Saxena ◽  
J. Karwowski
Keyword(s):  
Experimental Data ◽  
Ionization Potentials ◽  
Hartree Fock ◽  
Relativistic Corrections

Values of the first four ionization potentials have been calculated from Hartree–Fock energies, with and/or without the relativistic corrections, for the elements lithium to nobelium. The merit of the Hartree–Fock approximation, regarding the prediction of ionization potentials, is discussed by comparison to existing experimental data.

Atomic Ionization Potentials Derived from Theoretical Calculations

1975 ◽  
Vol 53 (21) ◽  
pp. 2415-2420 ◽  
Author(s):  
Serafin Fraga ◽  
K. M. S. Saxena ◽  
Jacek Karwowski ◽  
Brian Bray
Keyword(s):  
Experimental Data ◽  
Predictive Value ◽  
Theoretical Calculations ◽  
Ground States ◽  
Theoretical Method ◽  
Ionization Potentials ◽  
Hartree Fock ◽  
Atomic Ionization ◽  
Total Energies ◽  
Theoretical Results

A table of all the ionization potentials of the elements lithium through krypton is presented.These values have been derived from the theoretical results obtained, within the Hartree–Fock method and including all the relativistic corrections, for the total energies of the ground states. The characteristics of the theoretical method are briefly outlined.Comparison with available experimental data establishes the excellent predictive value of the theoretical results.

EELS white line intensities calculated for the 3d and 4d metals

1989 ◽  
Vol 47 ◽  
pp. 388-389
Author(s):  
C. C. Ahn ◽  
D. H. Pearson ◽  
P. Rez ◽  
B. Fultz
Keyword(s):  
Experimental Data ◽  
Line Intensity ◽  
Transition Probabilities ◽  
Initial Increase ◽  
White Line ◽  
Hartree Fock ◽  
Line Intensities ◽  
Integrated Intensity ◽  
X Ray Absorption ◽  
The Continuum

Previous experimental measurements of the total white line intensities from L2,3 energy loss spectra of 3d transition metals reported a linear dependence of the white line intensity on 3d occupancy. These results are inconsistent, however, with behavior inferred from relativistic one electron Dirac-Fock calculations, which show an initial increase followed by a decrease of total white line intensity across the 3d series. This inconsistency with experimental data is especially puzzling in light of work by Thole, et al., which successfully calculates x-ray absorption spectra of the lanthanide M4,5 white lines by employing a less rigorous Hartree-Fock calculation with relativistic corrections based on the work of Cowan. When restricted to transitions allowed by dipole selection rules, the calculated spectra of the lanthanide M4,5 white lines show a decreasing intensity as a function of Z that was consistent with the available experimental data.Here we report the results of Dirac-Fock calculations of the L2,3 white lines of the 3d and 4d elements, and compare the results to the experimental work of Pearson et al. In a previous study, similar calculations helped to account for the non-statistical behavior of L3/L2 ratios of the 3d metals. We assumed that all metals had a single 4s electron. Because these calculations provide absolute transition probabilities, to compare the calculated white line intensities to the experimental data, we normalized the calculated intensities to the intensity of the continuum above the L3 edges. The continuum intensity was obtained by Hartree-Slater calculations, and the normalization factor for the white line intensities was the integrated intensity in an energy window of fixed width and position above the L3 edge of each element.

scholarly journals THE METHOD OF INCREMENTS — A WAVEFUNCTION-BASED AB-INITIO CORRELATION METHOD FOR SOLIDS

2007 ◽  
Vol 21 (13n14) ◽  
pp. 2204-2214 ◽  
Author(s):  
BEATE PAULUS
Keyword(s):  
Experimental Data ◽  
Ab Initio ◽  
Ground State ◽  
Infinite System ◽  
Correlation Energy ◽  
Correlation Method ◽  
Many Body ◽  
Hartree Fock ◽  
The Many ◽  
Good Agreement

The method of increments is a wavefunction-based ab initio correlation method for solids, which explicitly calculates the many-body wavefunction of the system. After a Hartree-Fock treatment of the infinite system the correlation energy of the solid is expanded in terms of localised orbitals or of a group of localised orbitals. The method of increments has been applied to a great variety of materials with a band gap, but in this paper the extension to metals is described. The application to solid mercury is presented, where we achieve very good agreement of the calculated ground-state properties with the experimental data.

scholarly journals Differential and integral cross sections for electron elastic scattering by ammonia for incident energies ranging from 10 eV to 20 keV

2018 ◽  
Vol 64 (5) ◽  
pp. 498
Author(s):  
Hocine Aouchiche
Keyword(s):  
Experimental Data ◽  
Elastic Scattering ◽  
Cross Sections ◽  
Optical Potential ◽  
Large Set ◽  
Quantum Calculation ◽  
Hartree Fock ◽  
Spherical Complex ◽  
Static Part ◽  
Model Point

Differential and integral cross sections for elastic scattering of electron by NH3 molecule are investigated for the energy ranging from 10 eV to 20 keV.  The calculations are carried out in the framework of partial wave formalism describing the target molecule by means of one center molecular Hartree-Fock functions.  A spherical complex optical potential used includes a static part – obtained here numerically from quantum calculation – and fine effects like correlation, polarization and exchange potentials. The results obtained in this model point out clearly the role played by the exchange and the correlation-polarization contributions in particular at lower scattering angles and lower incident energies. Both differential and integral cross sections obtained are compared with a large set of experimental data available in the literature and well agreement is found throughout the scattering angles and whole energy range investigated here.

IONIZATION POTENTIALS OF ALKYL FREE RADICALS AND n-ALKANES THROUGH C17H36 BY ENERGY-CALIBRATED MOLECULAR ORBITAL METHODS

1966 ◽  
Vol 44 (12) ◽  
pp. 1455-1462 ◽  
Author(s):  
Charles E. Melton ◽  
Hubert W. Joy
Keyword(s):  
Experimental Data ◽  
Free Radicals ◽  
Molecular Orbital ◽  
Ionization Potentials ◽  
Recent Experimental Data ◽  
Normal Alkanes ◽  
Atomic Orbitals ◽  
Large Molecules ◽  
Good Agreement ◽  
Expansion Scheme

Ionization potentials are calculated by simple energy-calibrated molecular orbital techniques for the normal alkanes through C17H36 and for some normal and branched alkyl free radicals. A model is formulated which allows the computations to be extended to extremely large molecules by using "radical" orbitals as well as atomic orbitals in the expansion scheme. Auto-ionization levels as well as ionization potentials are calculated for the radicals. Computed and observed values are in good agreement where recent experimental data are available.

CRITICAL TEMPERATURE OF TRAPPED INTERACTING BOSE GASES

2009 ◽  
Vol 23 (12) ◽  
pp. 1499-1507
Author(s):  
CUILING ZHANG ◽  
LEI TAN ◽  
KUNYAN ZHU
Keyword(s):  
Experimental Data ◽  
Transition Temperature ◽  
Critical Temperature ◽  
Recent Experiment ◽  
Mutual Interaction ◽  
Condensate Fraction ◽  
Thermal Component ◽  
Bose Gases ◽  
New Model ◽  
Hartree Fock

A new model is proposed to study the effect of mutual interaction revealed in a recent experiment.1 Unlike conventional Hartree–Fock theory, which only studies onset interactions between indistinguishable interacting bosons, our model further includes the mutual interaction between the condensate component and the thermal component. The derived condensate fraction and transition temperature explain the experimental data in a reliable manner.

scholarly journals Radiative decays of scalar mesons σ(600), f 0(980) and a 0(980) in the local Nambu-Jona-Lasinio model

Open Physics ◽  
2010 ◽  
Vol 8 (4) ◽  
Author(s):  
Mikhail Volkov ◽  
Eduard Kuraev ◽  
Yury Bystritskiy
Keyword(s):  
Experimental Data ◽  
Dominant Role ◽  
Radiative Decays ◽  
Loop Contribution ◽  
Hartree Fock ◽  
Scalar Mesons ◽  
Two Photon ◽  
Photon Decay ◽  
Decay Widths ◽  
Order Of Magnitude

AbstractThe two-photon decay widths of scalar mesons σ(600), f 0(980) and a 0(980) as well a 0 → ju(ω)γ and f 0 → ju(ω)γ are calculated in the framework of the local Nambu-Jona-Lasinio model. The contributions of the quark loops (Hartree-Fock approximation) and the meson loops (next 1/N c-approximation where N c is the number of colors) are taken into account. The values of these contributions, as we show, are of the same order of magnitude. For the f 0 decay the K-loop contribution plays the dominant role. The results for two-gamma decays are in satisfactory agreement with modern experimental data. The predictions for a 0 → ju(ω)γ and f 0 → ju(ω)γ widths are given.

scholarly journals An analytical formula for proton momentum distribution in nuclei with A>4

2019 ◽  
Vol 10 ◽  
pp. 248
Author(s):  
G. S. Anagnostatos ◽  
A. N. Antonov ◽  
J. Giapitzakis ◽  
P. Ginis ◽  
S. E. Massen ◽  
...  
Keyword(s):  
Experimental Data ◽  
Shell Model ◽  
Momentum Distribution ◽  
Analytical Formula ◽  
Nucleon Nucleon ◽  
Exotic Nuclei ◽  
Wave Functions ◽  
Proton Momentum ◽  
Correlation Effects ◽  
Hartree Fock

A successful analytical formula for the proton momentum distribution in all nuclei with A>4 accounting for nucleon-nucleon correlation effects, is presented. In this formula the Isomorphic Shell Model wave functions are employed, which are readily available for all nuclei all the way up to 2 0 8Pb. However, other wave functions (e.g., shell model or Hartree-Fock) could be used with almost equivalent results. Available experimental data for 4He, 1 2C and 5 6Fe and predictions of other theories, e.g., for 4 0Ca, are used for comparison of the predictions of the present formula. A reservation is kept concerning the validity of this formula for the momentum distribution of exotic nuclei.

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