scholarly journals Alternative relativistic formulation of linear spectrum of hydrogen-like systems

2020 ◽  
pp. 171-181
Author(s):  
Ilya E. Eremin ◽  
Vitaliy V. Neshtimenko ◽  
Dmitry S. Shcherban ◽  
Denis V. Fomin
Keyword(s):  
Electronic Structure ◽  
Computational Complexity ◽  
Maximum Degree ◽  
Chemical Elements ◽  
Energy Levels ◽  
Quantum Processes ◽  
Degree Of Ionization ◽  
Atomic Systems ◽  
Relativistic Formulation ◽  
Linear Spectrum

The article describes the possibility of describing the electronic structure of the simplest atomic systems within corpuscular physics theory. The proposed method allows to derive the Rydberg frequency constant without using quantum Bohr postulates. Adequate results of the same type of calculation of the energy levels of the first five chemical elements that are in the maximum degree of ionization are presented. The results of the paper can increase the accuracy and reduce the computational complexity of models of quantum processes and phenomena. This, in turn, may allow one to develop more efficient models and algorithms for controlling such systems.

scholarly journals On the study of D. I. Mendeleev Periodical Law and the modern periodical system of chemical elements in the school chemistry course

2020 ◽  
pp. 51-58
Author(s):  
Sergey F. Zhiltsov ◽  
Olga N. Druzhkova ◽  
Svetlana A. Oparina
Keyword(s):  
Electronic Structure ◽  
Chemical Elements ◽  
Energy Levels ◽  
Atomic Mass ◽  
150Th Anniversary ◽  
Electronic Theory ◽  
Periodic Law ◽  
Further Development ◽  
Structure Of Matter

The article is dedicated to the 150th anniversary of D. I. Mendeleev’s periodical law, which establishes the dependence of changes in the properties of simple and complex substances on the atomic mass of elements. The main aspects of the study of this topic in the school course of chemistry on the basis of historical facts and information, as well as its further development in the light of electronic theory of the structure of matter are considered. Modern Periodical system of chemical elements on the basis of principles used by scientists and existing ideas about electronic structure of atoms is modeled for pupils. The periodic law is a reflection of the frequency with which electrons fill the energy levels of currently known 118 chemical elements.

scholarly journals Semiclassical calculations of the quadruple excited four-electron systems

2007 ◽  
pp. 33-44
Author(s):  
N. Simonovic ◽  
M. Predojevic ◽  
V. Pankovic ◽  
P. Grujic
Keyword(s):  
Energy Levels ◽  
Point Of View ◽  
Interstellar Space ◽  
Vibrational Modes ◽  
Electron Systems ◽  
Atomic Systems ◽  
Excited Atoms ◽  
Relative Contribution ◽  
Quantum Numbers ◽  
Semiclassical States

Highly excited atoms acquire very large dimensions and can be present only in a very rarified gas medium, such as the interstellar space. Multiply excited beryllium-like systems, when excited to large principal quantum numbers, have a radius of r ? 10 ?. We examine the semiclassical spectrum of quadruple highly excited four-electron atomic systems for the plane model of equivalent electrons. The energy of the system consists of rotational and vibrational modes within the almost circular orbit approximation, as used in a previous calculation for the triply excited three-electron systems. Here we present numerical results for the beryllium atom. The lifetimes of the semiclassical states are estimated via the corresponding Lyapunov exponents. The vibrational modes relative contribution to the energy levels rises with the degree of the Coulombic excitation. The relevance of the results is discussed both from the observational and heuristic point of view.

Quantograms as a New Visualization Technique of Electronic Structure of Atomic Systems

2021 ◽  
Vol 57 (2) ◽  
pp. 177-184
Author(s):  
O. I. Meshkov ◽  
V. V. Kazakov ◽  
V. G. Kazakov ◽  
A. A. Potekhin ◽  
E. A. Temnikova ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Visualization Technique ◽  
Atomic Systems

Electronic structure of dipeptides in the gas-phase and as an adsorbed monolayer

2018 ◽  
Vol 20 (10) ◽  
pp. 6860-6867 ◽  
Author(s):  
Cunlan Guo ◽  
Soumyajit Sarkar ◽  
Sivan Refaely-Abramson ◽  
David A. Egger ◽  
Tatyana Bendikov ◽  
...  
Keyword(s):  
Electronic Structure ◽  
Gas Phase ◽  
Energy Levels ◽  
Peptide Binding ◽  
Molecular Orbitals ◽  
Gold Substrate ◽  
Adsorbed Monolayer

UPS and DFT reveal how frontier energy levels and molecular orbitals of peptides are modified upon peptide binding to a gold substrate.

Small is different

2021 ◽  
pp. 81-93
Author(s):  
Adrian P Sutton
Keyword(s):  
Crystal Structure ◽  
Electronic Structure ◽  
Catalytic Activity ◽  
Giant Magnetoresistance ◽  
Energy Levels ◽  
Exclusion Principle ◽  
Thermodynamic Quantities ◽  
Discrete Energy ◽  
Size Dependent ◽  
The World

As the size of a material decreases to the nanoscale its properties become size-dependent. This is the world of nanoscience and nanotechnology. At the nanoscale the crystal structure may change and thermodynamic quantities such as the melting point also change. Changes in the catalytic activity and colour of nanoparticles suspended in a liquid indicate changes to the electronic structure. Quantum dots have discrete energy levels that can be modelled with the particle-in-a-box model. Excitons may be created in them using optical illumination, and their decay leads to fluorescence with distinct colours. The classical and quantum origins of magnetism are discussed. The origin of magnetoresistance in a ferromagnet is described and related to the exclusion principle. The origin of the giant magnetoresistance effect and its exploitation in nanotechnology is outlined.

Quantum processes in 8-Oxo-Guanine-Ru(bipyridine)32+ photosynthetic systems of artificial minimal cells

Open Physics ◽  
2011 ◽  
Vol 9 (3) ◽  
Author(s):  
Arvydas Tamulis ◽  
Mantas Grigalavicius ◽  
Sarunas Krisciukaitis ◽  
Giedrius Medzevicius
Keyword(s):  
Fatty Acid ◽  
Molecular Orbital ◽  
Electron Correlation ◽  
Self Assembly ◽  
Density Functional ◽  
Energy Levels ◽  
Critical Role ◽  
Quantum Processes ◽  
Photoexcited Electron ◽  
Minimal Cells

AbstractDensity functional theory methods were used to investigate various self-assembled photoactive bioorganic systems of interest for artificial minimal cells. The cell systems studied are based on nucleotides or their compounds and consisted of up to 123 atoms (not including the associated water or methanol solvent shells) and are up to 2.5 nm in diameter. The electron correlation interactions responsible for the weak hydrogen and Van derWaals chemical bonds increase due to the addition of a polar solvent (water or methanol). The precursor fatty acid molecules of the system also play a critical role in the quantum mechanical interaction based self-assembly of the photosynthetic center and the functioning of the photosynthetic processes of the artificial minimal cells. The distances between the separated sensitizer, fatty acid precursor, and methanol molecules are comparable to Van derWaals and hydrogen bonding radii. As a result the associated electron correlation interactions compress the overall system, resulting in an even smaller gap between the highest occupied molecular orbital (HOMO), and lowest unoccupied molecular orbital (LUMO) electron energy levels and photoexcited electron tunnelling occurs from the sensitizer (either Ru(bpy)32+ or [Ru(bpy)2(4-Bu-4’-Me-2,2’-bpy)]2++ derivatives) to the precursor fatty acid molecules (notation used: Me = methyl; Bu = butyl; bpy = bipyridine). The shift of the absorption spectrum to the red for the artificial protocell photosynthetic centers might be considered as the measure of the complexity of these systems.

Electronic Structure for a Distorted Chain

1972 ◽  
Vol 50 (11) ◽  
pp. 1078-1081
Author(s):  
T. C. Wong ◽  
B. Y. Tong
Keyword(s):  
Electronic Structure ◽  
Band Gap ◽  
Density Of States ◽  
Energy Levels ◽  
Linear Chain ◽  
Integrated Density Of States ◽  
Counting Method ◽  
Model Liquid ◽  
Impurity Atoms ◽  
Specific Manner

A linear chain with impurities randomly distributed along it is studied by means of the node counting method. The host atoms as well as the impurity atoms are represented by negative δ-function potentials with different strengths. The solvent atoms are distorted in a specific manner about each impurity atom. The integrated density of states are calculated near a band gap for different impurity concentrations and for various degrees of distortion. It was found that without distortion the gap remains practically structureless, whereas with distortion the energy levels diffuse into the gap. The results are qualitatively similar to that of a model liquid.

Analysis of electronic structure and optical properties of N-doped SiO2 based on DFT calculations

2015 ◽  
Vol 29 (19) ◽  
pp. 1550100 ◽  
Author(s):  
Sui-Shuan Zhang ◽  
Zong-Yan Zhao ◽  
Pei-Zhi Yang
Keyword(s):  
Optical Properties ◽  
Electronic Structure ◽  
Band Gap ◽  
Impurity Concentration ◽  
Nitrogen Concentration ◽  
Energy Levels ◽  
Optical Parameter ◽  
Doping Effects ◽  
N Doping ◽  
The Relationship

The crystal structure, electronic structure and optical properties of N-doped [Formula: see text] with different N impurity concentrations were calculated by density function theory within GGA[Formula: see text]+[Formula: see text]U method. The crystal distortion, impurity formation energy, band gap, band width and optical parameter of N-doped [Formula: see text] are closely related with N impurity concentration. Based on the calculated results, there are three new impurity energy levels emerging in the band gap of N-doped [Formula: see text], which determine the electronic structure and optical properties. The variations of optical properties induced by N doping are predominately determined by the unsaturated impurity states, which are more obvious at higher N impurity concentration. In addition, all the doping effects of N in both [Formula: see text]-quartz [Formula: see text] and [Formula: see text]-quartz [Formula: see text] are very similar. According to these findings, one could understand the relationship between nitrogen concentration and optical parameter of [Formula: see text] materials, and design new optoelectrionic Si–O–N compounds.

The electronic structure and magnetic properties of uranyl-like ions I. Uranyl and neptunyl

1955 ◽  
Vol 229 (1176) ◽  
pp. 20-38 ◽  
Keyword(s):  
Magnetic Properties ◽  
Absorption Spectrum ◽  
Electronic Structure ◽  
Unpaired Electron ◽  
Energy Levels ◽  
Uranyl Ion ◽  
Bonding Mechanism ◽  
Paramagnetic Resonance

A theory of the electronic bonding in the uranyl ion is given, on the basis of which the paramagnetism of uranyl can be explained. Assuming the same bonding mechanism to be effective in neptunyl, with one unpaired electron, its energy levels, absorption spectrum, paramagnetic resonance and susceptibility are discussed. Agreement with experiment is satisfactory. The evidence points clearly to f -electrons being responsible for the magnetism.

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