On singularities of electronic state density in liquid metals and disordered metallic alloys

1990 ◽  
Vol 80 (1) ◽  
pp. 63-71 ◽  
Author(s):  
M. I. Katsnelson ◽  
A. V. Trefilov
Keyword(s):  
Electronic State ◽  
Liquid Metals ◽  
State Density ◽  
Metallic Alloys ◽  
Electronic State Density

scholarly journals X-ray spectroscopy study of ThO2 and ThF4

2010 ◽  
Vol 25 (1) ◽  
pp. 8-12
Author(s):  
Anton Teterin ◽  
Mikhail Ryzhkov ◽  
Yury Teterin ◽  
Ernst Kurmaev ◽  
Konstantin Maslakov ◽  
...  
Keyword(s):  
Binding Energy ◽  
Energy Range ◽  
Density Distribution ◽  
Electronic State ◽  
Electronic States ◽  
State Density ◽  
Molecular Orbitals ◽  
Spectral Structure ◽  
X Ray ◽  
Electronic State Density

The structure of the X-ray photoelectron, X-ray O(F)Ka-emission spectra from ThO2 and ThF4 as well as the Auger OKLL spectra from ThO2 was studied. The spectral structure was analyzed by using fully relativistic cluster discrete variational calculations of the electronic structure of the ThO8 D4h) and ThF8 (C2) clusters reflecting thorium close environment in solid ThO2 and ThF4. As a result it was theoretically found and experimentally confirmed that during the chemical bond formation the filled O(F)2p electronic states are distributed mainly in the binding energy range of the outer valence molecular orbitals from 0-13 eV, while the filled O(F)2s electronic states - in the binding energy range of the inner valence molecular orbitals from 13-35 eV. It was shown that the Auger OKLL spectral structure from ThO2 characterizes not only the O2p electronic state density distribution, but also the O2s electronic state density distribution. It agrees with the suggestion that O2s electrons participate in formation of the inner valence molecular orbitals, in the binding energy range of 13-35 eV. The relative Auger OKL2-3L2-3 peak intensity was shown to reflect quantitatively the O2p electronic state density of the oxygen ion in ThO2.

Electronic state density of highly conducting polyacetylene

1991 ◽  
Vol 41 (1-2) ◽  
pp. 117-120 ◽  
Author(s):  
Y. Nogami ◽  
H. Kaneko ◽  
T. Ishiguro ◽  
N. Hosoito ◽  
J. Tsukamoto ◽  
...  
Keyword(s):  
Electronic State ◽  
State Density ◽  
Electronic State Density

scholarly journals Valence electronic state density in thorium dioxide

2008 ◽  
Vol 23 (2) ◽  
pp. 34-42 ◽  
Author(s):  
Anton Teterin ◽  
Mikhail Ryzhkov ◽  
Yury Teterin ◽  
Labud Vukcevic ◽  
Vladimir Terekhov ◽  
...  
Keyword(s):  
Electronic State ◽  
State Density ◽  
Molecular Orbitals ◽  
Photoelectron Spectra ◽  
Spectral Structure ◽  
Discrete Variation ◽  
Thorium Dioxide ◽  
X Ray ◽  
Electronic State Density ◽  
First Time

This work analyses the fine low energy (0-40 eV) X-ray photoelectron spectra of ThO2, taking into account relativistic X?-discrete variation electronic structure calculations for the ThO8 (D4h) cluster reflecting thorium's close environment in ThO2. As a result, it was theoretically shown and experimentally confirmed that Th5f electrons in ThO2 can participate directly (~0.6 Th5f electrons) in chemical bond formation.Th6p electrons were shown to be a significant part (~0.44 Th6p electrons) not only of inner valence molecular orbitals, but to play a significant role in outer valence molecular orbitals formation, as well. Inner valence molecular orbitals composition and sequent order were established to belong to the binding energy range of 13 eV to 40 eV. The valence electronic state density in the range of 0-40 eV in ThO2 was also calculated. For the first time, these data allowed an interpretation of the fine X-ray photoelectron spectra (0-40 eV) and high resolution O4,5(Th) X-ray emition spectral structure (~60 - ~85 eV) of ThO2.

scholarly journals Особенности электронной структуры интерметаллических соединений CeNi-=SUB=-4-=/SUB=-M (M=Fe, Co, Ni, Cu)

2018 ◽  
Vol 60 (3) ◽  
pp. 461
Author(s):  
А.В. Лукоянов ◽  
А.А. Широков
Keyword(s):  
Electronic Structure ◽  
Fermi Level ◽  
Total Energy ◽  
Electronic State ◽  
Magnetic Moments ◽  
State Density ◽  
Total Density ◽  
Substitutional Impurity ◽  
Self Consistent ◽  
Electronic State Density

AbstractThe evolution of the electronic structure of CeNi_4M (M = Fe, Co, Ni, Cu) intermetallics depending on the type of nickel substitutional impurity is explored. We have calculated band structures of these compounds and considered options of substituting one atom in nickel 3 d sublattice in both types of crystallographic positions: 2 c and 3 g . The analysis of total energy self-consistent calculations has shown that positions of 2 c type are more energetically advantageous for single iron and cobalt impurities, whereas a position of 3 g type is better for a copper impurity. The Cu substitutional impurity does not change either the nonmagnetic state of ions or the total density at the Fermi level states. Fe and Co impurities, on the contrary, due to their considerable magnetic moments, induce magnetization of 3 d states of nickel and cause significant changes in the electronic state density at the Fermi level.

Bulk Glass-Forming Metallic Alloys: Science and Technology

MRS Bulletin ◽  
1999 ◽  
Vol 24 (10) ◽  
pp. 42-56 ◽  
Author(s):  
William L. Johnson
Keyword(s):  
Metallic Glasses ◽  
Liquid Metals ◽  
Rapid Quenching ◽  
Metallic Alloys ◽  
Bulk Glass ◽  
Related Field ◽  
Glass Forming ◽  
Metallic Liquids ◽  
Potential Applications ◽  
Liquid Metal Alloy

The following article is based on the MRS Medal talk presented by William L. Johnson at the 1998 MRS Fall Meeting on December 2, 1998. The MRS Medal is awarded for a specific outstanding recent discovery or advancement that has a major impact on the progress of a materials-related field. Johnson received the honor for his development of bulk metallic glass-forming alloys, the fundamental understanding of the thermodynamics and kinetics that control glass formation and crystallization of glass-forming liquids, and the application of these materials in engineering.The development of bulk glass-forming metallic alloys has led to interesting advances in the science of liquid metals. This article begins with brief remarks about the history and background of the field, then follows with a discussion of multicomponent glass-forming alloys and deep eutectics, the chemical constitution of these new alloys, and how they differ from metallic glasses of a decade ago or earlier. Recent studies of deeply undercooled liquid alloys and the insights made possible by their exceptional stability with respect to crystallization will then be discussed. Advances in this area will be illustrated by several examples. The article then describes some of the physical and specific mechanical properties of bulk metallic glasses (BMGs), and concludes with some interesting potential applications.The first liquid-metal alloy vitrified by cooling from the molten state to the glass transition was Au-Si, as reported by Duwez at Caltech in 1960. Duwez made this discovery as a result of developing rapid quenching techniques for chilling metallic liquids at very high rates of 105–106 K/s.

Thermal conductivity of liquid metals and metallic alloys

1999 ◽  
Vol 250-252 ◽  
pp. 377-383 ◽  
Author(s):  
B. Giordanengo ◽  
N. Benazzi ◽  
J. Vinckel ◽  
J.G. Gasser ◽  
L. Roubi
Keyword(s):  
Thermal Conductivity ◽  
Liquid Metals ◽  
Metallic Alloys

scholarly journals Influence of structural changes on electrical and magnetic properties of the Co84Fe5,3Si8,5B2,2 amorphous alloy

2005 ◽  
Vol 37 (3) ◽  
pp. 231-235 ◽  
Author(s):  
S.R. Djukic ◽  
Radojko Simeunovic ◽  
Aleksa Maricic
Keyword(s):  
Activation Energy ◽  
Amorphous Alloy ◽  
Relaxation Process ◽  
Structural Changes ◽  
Crystallization Process ◽  
State Density ◽  
Annealing Process ◽  
Scanning Calorimetry ◽  
Electrical And Magnetic Properties ◽  
Electronic State Density

The crystallization process of the Co84Fe5.3Si8.5B2.2 amorphous alloy examined by differential scanning calorimetry (DSC) exhibits three exothermal steps at Tcr1=649K, Tcr2=800K, and Tcr3=838K. The rate constants of the first relaxation process (determined at 598K and 623K) are k1=5*10-4 s and k2=8*10-4 s and the corresponding activation energy Ea1=26.23 kJ/mol. The data for the relaxation process before the second crystallization step (determined at 683K and 713K) are k3=14.5*10-4 s and k4=17.5*10-4 s and the corresponding activation energy Ea2=60.0 kJ/mol. The process of structural relaxation in non-isothermal and isothermal conditions was studied by analysis of the results of measurements of the thermo electromotive force (TEMF). From the change of the temperature coefficient of TEMF that follows each annealing process, the relative electronic state density changes at the Fermi level were determined: ?N21/N2=5,45%, ?N22/N2=5,76%, ?N23/N2=7,57% and ?N24/N2=9,85%.

TEM study of amorphization of Cu and Ti foils by cold-rolling

1990 ◽  
Vol 48 (4) ◽  
pp. 146-147
Author(s):  
W. A. Chiou ◽  
N. L. Jeon ◽  
Genbao Xu ◽  
M. Meshii
Keyword(s):  
Solid State ◽  
Cold Rolling ◽  
High Energy ◽  
Rapid Quenching ◽  
Vapor Condensation ◽  
Metallic Alloys ◽  
Solid State Reactions ◽  
High Energy Particle ◽  
Amorphous Metallic Alloys ◽  
Thin Foils

For many years amorphous metallic alloys have been prepared by rapid quenching techniques such as vapor condensation or melt quenching. Recently, solid-state reactions have shown to be an alternative for synthesizing amorphous metallic alloys. While solid-state amorphization by ball milling and high energy particle irradiation have been investigated extensively, the growth of amorphous phase by cold-rolling has been limited. This paper presents a morphological and structural study of amorphization of Cu and Ti foils by rolling.Samples of high purity Cu (99.999%) and Ti (99.99%) foils with a thickness of 0.025 mm were used as starting materials. These thin foils were cut to 5 cm (w) × 10 cm (1), and the surface was cleaned with acetone. A total of twenty alternatively stacked Cu and Ti foils were then rolled. Composite layers following each rolling pass were cleaned with acetone, cut into half and stacked together, and then rolled again.

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