Victor Yarzhemsky - Academia.edu (original) (raw)
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Papers by Victor Yarzhemsky
Inorganic Materials, 2005
Optics and Spectroscopy, 2004
Relativistic calculations of the angular distribution of photoelectrons upon photoionization of 2... more Relativistic calculations of the angular distribution of photoelectrons upon photoionization of 2p and 3d shells in the range of photoelectron energies from 1 to 10 keV are carried out for unpolarized and linearly polarized radiation. An exact expression for the angular distribution of photoelectrons that takes into account nondipolar terms of the order of O[(kr)2] (k is the photon energy and r is the radius of the ionized shell) is obtained in the case of unpolarized radiation. It is shown that the contribution of the O[(kr)2] terms to the differential cross section can be considerable, reaching 24% at the maximum energy considered. Accounting for such terms in the calculation of the ratio of differential cross sections, which is experimentally measured at a certain geometry of angles in the case of linearly polarized radiation, can change this ratio twofold. The parameters of the angular distribution, which are necessary for the conduction of a quantitative x-ray photoelectron analysis, are given for the 2p 1/2 and 2p 3/2 shells of elements with 11≤Z≤29 and for the 3d 3/2 and 3d 5/2 shells of elements with 30≤Z≤54.
Journal of Physics B: Atomic, Molecular and Optical Physics, 2001
ABSTRACT
Journal of Electron Spectroscopy and Related Phenomena, 1994
Journal of Electron Spectroscopy and Related Phenomena, 2005
ABSTRACT Using the transport theory approach, equations are derived for the angular dependence of... more ABSTRACT Using the transport theory approach, equations are derived for the angular dependence of XPS intensities from semi-infinite solids taking into account elastic scattering of photoelectrons and non-dipolar transitions up the second-order corrections. The unpolarized excitation source is considered. The elastic scattering is the main term smearing the non-dipolar contribution in complete analogy with smearing of dipole contribution. Some additional terms are shown to be negligible in comparison with the main term for complete sets of emission and azimuth angles, three representative single scattering albedo values and several representative sets of the second-order non-dipolar parameters. The photoelectron angular distributions are calculated for Al 2s and Ag 3d lines using transport theory and Monte-Carlo simulation. The Monte-Carlo calculations are in agreement with transport theory approach.
Journal of Electron Spectroscopy and Related Phenomena, 2003
Journal of Electron Spectroscopy and Related Phenomena, 2003
Using the transport theory approach, equations are derived for the angular dependence of X-ray ph... more Using the transport theory approach, equations are derived for the angular dependence of X-ray photoelectron spectroscopy intensities from semi-infinite solids taking into account elastic scattering of photoelectrons and non-dipolar transitions up the second order corrections. The linearly polarized source is considered. The elastic scattering presented by the main term smeared the non-dipolar contribution in complete analogy with smearing of dipole
Journal of Electron Spectroscopy and Related Phenomena, 2002
The main photoelectron line spectroscopic factors that are currently used in photoelectron spectr... more The main photoelectron line spectroscopic factors that are currently used in photoelectron spectroscopy for quantitative analysis are calculated for a broad set of atoms. General trends of the behaviour of the spectroscopic factors of core atomic levels are discussed. The influence of the spectroscopic factors on the main line intensities and on concentrations of the elements, that are obtained using X-ray photoelectron spectra, is analysed.
International Journal of Theoretical Physics, 2006
The point subgroups of index 2 of hypercubic group and their irreducible representations are obta... more The point subgroups of index 2 of hypercubic group and their irreducible representations are obtained. The elements of the hypercubic group are represented as rotation about two axis. Possible physical meaning of hypercubic group for electron states is investigated. The reduction relations for the representations of orthogonal group O4 on hypercubic group are obtained. These relations are used for additional classification of electron states in crystals.
Doklady Physics, 2007
ABSTRACT A group theoretical method for constructing and analyzing the structure of two-electron ... more ABSTRACT A group theoretical method for constructing and analyzing the structure of two-electron states in crystals and its application to particular materials is presented. The induced-representation method or the projection-operator method can be used to construct the singlet and triplet two-electron wave functions transformed according to the irreducible representations of the symmetry group. The difference between the symmetry groups of the coordinate and spin subsystem allows to choose the symmetry of the two-electron state so that the spatial operators act only on the coordinate part, and time reversal, only on the spin part. The group theoretical method makes it possible to reveal the dependence of their structure on the symmetry group.
Doklady Physics, 2005
1. The main characteristic of unusual superconductors such as heavy-fermion superconductors and h... more 1. The main characteristic of unusual superconductors such as heavy-fermion superconductors and hightemperature superconductors (HTSCs) is that the superconducting order parameter (SOP) vanishes at points and lines of the Fermi surface [1‐3]. For spherically symmetric interaction, the SOP coincides with the wave function of a Cooper pair.
Doklady Physics, 2003
Without Abstract
Doklady Physics, 2003
Without Abstract
arXiv (Cornell University), Apr 21, 2011
Journal of Physics B: Atomic and Molecular Physics, 1985
ABSTRACT
Journal of Physics B: Atomic, Molecular and Optical Physics, 1995
ABSTRACT
Journal of Physics B: Atomic, Molecular and Optical Physics, 1993
ABSTRACT
Inorganic Materials, 2014
Experimental data on the symmetry of the superconducting state in the high T c superconductors ba... more Experimental data on the symmetry of the superconducting state in the high T c superconductors based on copper oxides and iron pnictides have been analyzed using a space group approach to the wavefunc tion of a Cooper pair. We have found the irreducible representations of the crystal symmetry groups of these materials for singlet states with zero total momentum corresponding to experimental data on the structure of their order parameter.
Inorganic Materials, 2005
Optics and Spectroscopy, 2004
Relativistic calculations of the angular distribution of photoelectrons upon photoionization of 2... more Relativistic calculations of the angular distribution of photoelectrons upon photoionization of 2p and 3d shells in the range of photoelectron energies from 1 to 10 keV are carried out for unpolarized and linearly polarized radiation. An exact expression for the angular distribution of photoelectrons that takes into account nondipolar terms of the order of O[(kr)2] (k is the photon energy and r is the radius of the ionized shell) is obtained in the case of unpolarized radiation. It is shown that the contribution of the O[(kr)2] terms to the differential cross section can be considerable, reaching 24% at the maximum energy considered. Accounting for such terms in the calculation of the ratio of differential cross sections, which is experimentally measured at a certain geometry of angles in the case of linearly polarized radiation, can change this ratio twofold. The parameters of the angular distribution, which are necessary for the conduction of a quantitative x-ray photoelectron analysis, are given for the 2p 1/2 and 2p 3/2 shells of elements with 11≤Z≤29 and for the 3d 3/2 and 3d 5/2 shells of elements with 30≤Z≤54.
Journal of Physics B: Atomic, Molecular and Optical Physics, 2001
ABSTRACT
Journal of Electron Spectroscopy and Related Phenomena, 1994
Journal of Electron Spectroscopy and Related Phenomena, 2005
ABSTRACT Using the transport theory approach, equations are derived for the angular dependence of... more ABSTRACT Using the transport theory approach, equations are derived for the angular dependence of XPS intensities from semi-infinite solids taking into account elastic scattering of photoelectrons and non-dipolar transitions up the second-order corrections. The unpolarized excitation source is considered. The elastic scattering is the main term smearing the non-dipolar contribution in complete analogy with smearing of dipole contribution. Some additional terms are shown to be negligible in comparison with the main term for complete sets of emission and azimuth angles, three representative single scattering albedo values and several representative sets of the second-order non-dipolar parameters. The photoelectron angular distributions are calculated for Al 2s and Ag 3d lines using transport theory and Monte-Carlo simulation. The Monte-Carlo calculations are in agreement with transport theory approach.
Journal of Electron Spectroscopy and Related Phenomena, 2003
Journal of Electron Spectroscopy and Related Phenomena, 2003
Using the transport theory approach, equations are derived for the angular dependence of X-ray ph... more Using the transport theory approach, equations are derived for the angular dependence of X-ray photoelectron spectroscopy intensities from semi-infinite solids taking into account elastic scattering of photoelectrons and non-dipolar transitions up the second order corrections. The linearly polarized source is considered. The elastic scattering presented by the main term smeared the non-dipolar contribution in complete analogy with smearing of dipole
Journal of Electron Spectroscopy and Related Phenomena, 2002
The main photoelectron line spectroscopic factors that are currently used in photoelectron spectr... more The main photoelectron line spectroscopic factors that are currently used in photoelectron spectroscopy for quantitative analysis are calculated for a broad set of atoms. General trends of the behaviour of the spectroscopic factors of core atomic levels are discussed. The influence of the spectroscopic factors on the main line intensities and on concentrations of the elements, that are obtained using X-ray photoelectron spectra, is analysed.
International Journal of Theoretical Physics, 2006
The point subgroups of index 2 of hypercubic group and their irreducible representations are obta... more The point subgroups of index 2 of hypercubic group and their irreducible representations are obtained. The elements of the hypercubic group are represented as rotation about two axis. Possible physical meaning of hypercubic group for electron states is investigated. The reduction relations for the representations of orthogonal group O4 on hypercubic group are obtained. These relations are used for additional classification of electron states in crystals.
Doklady Physics, 2007
ABSTRACT A group theoretical method for constructing and analyzing the structure of two-electron ... more ABSTRACT A group theoretical method for constructing and analyzing the structure of two-electron states in crystals and its application to particular materials is presented. The induced-representation method or the projection-operator method can be used to construct the singlet and triplet two-electron wave functions transformed according to the irreducible representations of the symmetry group. The difference between the symmetry groups of the coordinate and spin subsystem allows to choose the symmetry of the two-electron state so that the spatial operators act only on the coordinate part, and time reversal, only on the spin part. The group theoretical method makes it possible to reveal the dependence of their structure on the symmetry group.
Doklady Physics, 2005
1. The main characteristic of unusual superconductors such as heavy-fermion superconductors and h... more 1. The main characteristic of unusual superconductors such as heavy-fermion superconductors and hightemperature superconductors (HTSCs) is that the superconducting order parameter (SOP) vanishes at points and lines of the Fermi surface [1‐3]. For spherically symmetric interaction, the SOP coincides with the wave function of a Cooper pair.
Doklady Physics, 2003
Without Abstract
Doklady Physics, 2003
Without Abstract
arXiv (Cornell University), Apr 21, 2011
Journal of Physics B: Atomic and Molecular Physics, 1985
ABSTRACT
Journal of Physics B: Atomic, Molecular and Optical Physics, 1995
ABSTRACT
Journal of Physics B: Atomic, Molecular and Optical Physics, 1993
ABSTRACT
Inorganic Materials, 2014
Experimental data on the symmetry of the superconducting state in the high T c superconductors ba... more Experimental data on the symmetry of the superconducting state in the high T c superconductors based on copper oxides and iron pnictides have been analyzed using a space group approach to the wavefunc tion of a Cooper pair. We have found the irreducible representations of the crystal symmetry groups of these materials for singlet states with zero total momentum corresponding to experimental data on the structure of their order parameter.