Articoli di riviste: "Electron configuration"

1

Pressler, David E. "Atomic Electron Configuration". International Journal of Modern Physics A 16, supp01c (settembre 2001): 922–24. http://dx.doi.org/10.1142/s0217751x01008503.

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In this work I suggest that early twentieth century theoretical physicists did not have enough facts or experimental data to formulate a consistent atomic model and as a result the concept of the atom needs revised. I conclude that the new atomic model presented is based only on first principles, is easy to understand and visualize, and provides such a significant theoretical advance as to be a final theory.

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2

Yang, Qing, e J. D. Fan. "Topologic configuration of electron". Modern Physics Letters A 33, n. 26 (24 agosto 2018): 1850163. http://dx.doi.org/10.1142/s0217732318501638.

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Motion of an electron is much different from that of a kind of matter in classical mechanics. Although it is impossible to directly observe the configuration of a bare electron, it is never as simple as to treat it as a three-dimensional (3D) particle in the microscopic world because the electron itself certainly has its own topological configuration, so that it presents a field of a unit charge and a spin, etc. An electron produces a magnetic field in motion and also can radiate or absorb an electromagnetic field in its accelerating motions. Thus, the topological configuration of an electron must be related or similar to the configurations of the magnetic field and electromagnetic wave. Starting from the topological configuration of a single electromagnetic wave, it is possible to derive that an electron is a quantized left-hand Möbius strip, on the center of which there exists an anti-neutrino. The Möbius strip excites a [Formula: see text] circumference of a unit negative charge and a linear electric field of a [Formula: see text] torsion and can explain the wave feature of the electron and the essential cause of producing a magnetic field and radiating an electromagnetic wave as well as predict that the second-order tensor field among the three quarks in a proton has a topological configuration of right-hand three-leaf knot and can excite a [Formula: see text] circumference of a unit positive charge and a linear electric field of a [Formula: see text] torsion, which is just allelomorphic to an electron.

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3

Mercero, José M., Joseph E. Fowler, Cecilia Sarasola e Jesus M. Ugalde. "Atomic configuration-interaction electron-electron counterbalance densities". Physical Review A 59, n. 6 (1 giugno 1999): 4255–58. http://dx.doi.org/10.1103/physreva.59.4255.

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4

Ulianov MSc, PhD, Policarpo Yoshin. "Comparison of pauling and Ulianov electron distribution models". Material Science & Engineering International Journal 8, n. 2 (27 maggio 2024): 49–54. http://dx.doi.org/10.15406/mseij.2024.08.00235.

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This study presents a comprehensive comparison between the traditional Pauling electron distribution model and the innovative Ulianov model proposed by Dr. Policarpo Yoshin Ulianov. The Pauling model, which relies on the Aufbau principle, Hund’s rule, and the Pauli Exclusion Principle, has been a cornerstone in understanding electron configurations within atoms, organizing electrons into s, p, d, and f orbitals. In contrast, the Ulianov model introduces a novel linear progression for electron occupancy, proposing additional orbitals (g and h) to account for electron distribution in a manner that deviates from conventional methodologies. Through an analytical comparison, this paper evaluates both models in terms of functionality, energy levels, and methodology, highlighting the advantages and disadvantages inherent to each. The Pauling model is recognized for its empirical support and wide acceptance, offering a well-established framework for electron configuration. Meanwhile, the Ulianov model provides a fresh perspective that could potentially explain anomalies unaddressed by the Pauling model and predict new chemical properties, despite its current lack of empirical validation. Concluding, while the Pauling model remains the standard for electron configuration, the Ulianov model’s innovative approach challenges existing paradigms and invites further investigation into its validity and potential applications in the scientific community.

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Mulyawati, Tin, e Eka Purwanda. "Implementasi Alat Peraga “Ikon-E” Merupakan Kunci Sukses Memahami Konfigurasi Elektron (Cara Pengisian Konfigurasi Elektron Sebagai Media Pembelajaran Inovatif di SMA)". NUSRA : Jurnal Penelitian dan Ilmu Pendidikan 5, n. 2 (28 maggio 2024): 700–706. http://dx.doi.org/10.55681/nusra.v5i2.2631.

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This research aims to evaluate the effectiveness of using electron configuration content tools ("e-icons") as a learning medium at the Senior High School (SMA) level. Electron configuration is an important concept in chemistry and understanding it can improve students' understanding of class X atomic structure material. Research data will be collected through a knowledge test on the group of students who use the "e-ikon" tool, called the experimental group, and the group of students without using the "e-ikon" tool, called the control group. Also, through a questionnaire that assesses students' perceptions of the use of electron configuration content tools. Data analysis will be conducted to determine whether the use of the electron configuration content tool can improve students' understanding and help them better internalize the concept of electron configuration. The conclusion that can be drawn is that the scores of students from the experimental class group have a higher average score than the average scores of students from the control class group. This means that the "e-icon" tool has a real influence on students in understanding electron configurations. The time needed for teachers to explain is shorter with the help of the “e-icon” tool. Students become happier studying chemistry. Filling in the configuration using tools lasts a long time in the student's memory.

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Stojković, S. M., J. P. Šetrajčić e Igor Vragović. "Electron Configuration of Carbon Nanotubes". Materials Science Forum 352 (agosto 2000): 129–34. http://dx.doi.org/10.4028/www.scientific.net/msf.352.129.

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7

Pe rez-Garrido, M. Ortun-O, A. M. S, A. "Configuration space in electron glasses". Philosophical Magazine B 81, n. 2 (1 febbraio 2001): 151–62. http://dx.doi.org/10.1080/13642810010009366.

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8

Pérez-Garrido, A., M. Ortuño, A. M. Somoza e A. Díaz-Sánchez. "Configuration space in electron glasses". Philosophical Magazine B 81, n. 2 (febbraio 2001): 151–62. http://dx.doi.org/10.1080/13642810108216532.

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9

Kumar, Amit, Krishna Katuri, Piet Lens e Dónal Leech. "Does bioelectrochemical cell configuration and anode potential affect biofilm response?" Biochemical Society Transactions 40, n. 6 (21 novembre 2012): 1308–14. http://dx.doi.org/10.1042/bst20120130.

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Electrochemical gradients are the backbone of basic cellular functions, including chemo-osmotic transport and ATP synthesis. Microbial growth, terminal respiratory proteins and external electron transfer are major pathways competing for electrons. In BESs (bioelectrochemical systems), such as MFCs (microbial fuel cells), the electron flow can be via soluble inorganic/organic molecules or to a solid surface. The flow of electrons towards a solid surface can be via outer-membrane cytochromes or electron-shuttle molecules, mediated by conductive protein nanowires or extracellular matrices. In MECs (microbial electrolysis cells), the anode potential can vary over a wide range, which alters the thermodynamic energy available for bacteria capable of donating electrons to the electrode [termed EAB (electroactive bacteria)]. Thus the anode potential is an important electrochemical parameter determining the growth, electron distribution/transfer and electrical activity of films of these bacteria on electrodes. Different optimal applied potentials to anodes have been suggested in the literature, for selection for microbial growth, diversity and performance in biofilms on electrodes. In the present paper, we review the effects of anode potentials on electron-transfer properties of such biofilms, and report on the effect that electrochemical cell configuration may have on performance.

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Morehouse, Aaron, Kelton C. Ireland e Gobinda C. Saha. "An Investigation into the Effects of Electric Field Uniformity on Electrospun TPU Fiber Nano-Scale Morphology". Micromachines 14, n. 1 (13 gennaio 2023): 199. http://dx.doi.org/10.3390/mi14010199.

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ANSYS Maxwell was used to replicate the conditions of two potential electrospinning configurations: a needle–plate and a parallel-plate configuration. Simulations showed that the electric field generated within the parallel-plate configuration was much more uniform than that within the needle–plate configuration. Both configurations were assembled and used electrospin fibers at three different spinning distances (10 cm, 12 cm, and 15 cm), at a consistent electric field strength of 1.7 kV/cm. Scanning electron microscopy was used to compare the morphologies of the fibers produced in both configurations in order to confirm whether a more uniform electric field yielded thinner fibers. The results show that the needle–plate configuration produced finer fibers than the parallel-plate configuration at all three spinning distances. However, there was no difference in the fiber diameters produced at the 12 and 15 cm spinning distances within the needle–plate configuration, implying thinning may only occur up to a certain distance in this configuration.

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McGarrah, D. B., e M. L. Brake. "Argon ion excitation by relativistic electrons: I. Collision cross sections and deposition efficiencies". Laser and Particle Beams 8, n. 3 (settembre 1990): 493–506. http://dx.doi.org/10.1017/s0263034600008739.

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Calculations of the electron impact excitation cross sections and deposition efficiencies for singly ionized argon with electrons of energies up to and including relativistic values have been made using the first Born approximation and the generalized oscillator formalism. Deposition efficiencies for fast electrons were generated from the Peterson and Green integral equation. Cross sections and efficiencies were produced for 29 transitions from the ground state configuration of Arii to excited energy levels with (Ne)3s23p44s and (Ne)3s23p43d configurations and for 40 transitions between excited energy levels from 4s and 3d to 4p orbitals. Efficiencies are constant for electron energies above 1 keV to 10 MeV. Electrons ejected from inner shells contribute up to 12% of the efficiency of the transition for electrons above 10 keV.

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12

Liu, Rulin, Liang Fang, Yue Hao e Yaqing Chi. "Influence of Oxygen Vacancy Density on the Polaronic Configuration in Rutile". Materials 11, n. 11 (1 novembre 2018): 2156. http://dx.doi.org/10.3390/ma11112156.

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Polaronic configurations that were introduced by oxygen vacancy in rutile TiO2 crystal have been studied by the DFT + U method. It is found that the building block of TiO6 will expand when extra electron is trapped in the central Ti atom as polaron. With manually adjusting the initial geometry of oxygen vacancy structure, a variety of polaronic configurations are obtained after variable-cell relaxation. By calculating different sizes of supercell model, it is found that the most stable configuration can be influenced by the density of oxygen vacancy. With increasing interaction between vacancies, the most stable polaronic configuration change from small polaronic configuration to mixed configuration.

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13

Toman, Petr, Stanislav Nešpůrek e Kyuya Yakushi. "Electronic states and infrared spectroscopy of Ni- and Co-phthalocyanines: neutral and oxidized forms". Journal of Porphyrins and Phthalocyanines 06, n. 09 (settembre 2002): 556–62. http://dx.doi.org/10.1142/s1088424602000695.

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Quantum chemical calculations reproduced the experimental infrared spectra of NiPc , NiPc ( AsF 6)0.5, CoPc , and CoPc ( AsF 6)0.5. The agreement in the changes of line intensities supports the ligand-centered oxidation in both NiPc ( AsF 6)0.5 and CoPc ( AsF 6)0.5. Whereas, electron configurations of NiPc and NiPc + as well as CoPc represent standard cases, i.e. they can be taken as a closed-shell and open-shell system, respectively, the electron configuration of CoPc + must be taken as an open-shell system (while the number of electrons is even) to get an agreement of theoretical and experimental infrared spectra.

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14

ROTONDO, MICHAEL, JORGE A. RUEDA, REMO RUFFINI e SHE-SHENG XUE. "ON DEGENERATE COMPRESSED ATOMS AND COMPRESSED NUCLEAR MATTER CORES OF STELLAR DIMENSIONS". International Journal of Modern Physics: Conference Series 12 (gennaio 2012): 203–12. http://dx.doi.org/10.1142/s2010194512006393.

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The relativistic generalization of the Feynman, Metropolis and Teller treatment of compressed atoms is obtained. Each atomic configuration is confined by a Wigner-Seitz cell and is characterized by a positive electron Fermi energy. There exists a limiting configuration, reached when the Wigner-Seitz cell radius equals the radius of the nucleus, with a maximum value of the electron Fermi energy [Formula: see text], here expressed analytically in the ultra-relativistic approximation. The treatment is then extrapolated to compressed nuclear matter cores of stellar dimensions with A ≃ (m Planck /mn)3 ~ 1057 or Mcore ~ M⊙. A new family of equilibrium configurations exists for selected values of the electron Fermi energy varying in the range [Formula: see text]. Such configurations fulfill global but not local charge neutrality. They have electric fields on the core surface, increasing for decreasing values of the electron Fermi energy reaching values much larger than the critical value [Formula: see text], for [Formula: see text].

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15

Malker, Pooja, e Lalita Sharma. "Electron Impact Excitation of Ge-like Te20+–Cd16+ Ions". Atoms 10, n. 1 (7 febbraio 2022): 17. http://dx.doi.org/10.3390/atoms10010017.

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We study electron impact excitation of dipole allowed transitions in the extreme ultraviolet range—8–55 nm—for the germanium isoelectronic sequence Te20+–Cd16+. The fine structure transitions between the ground state having configuration 4s24p2 and the excited states with configurations 4s4p3 and 4s24p4d are considered for these ions. We employ the relativistic distorted wave method to calculate the excitation cross sections in the incident electron energy range from the excitation threshold to 5000 eV. To obtain the required ionic bound state wavefunctions we have used the multi-configuration Dirac-Fock method with correlations within the n = 5 complexes as well as performed relativistic configuration interaction calculations to include the quantum electrodynamic effects. The accuracy of these wavefunctions is established by comparing our calculated wavelengths and oscillator strengths of the considered transitions with the previously reported measurements and other available theoretical results. We also provide the fitting parameters of the calculated cross sections and the excitation rate coefficients for their direct applications in plasma modeling.

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16

Kanazawa, I. "The Electron Localization in the Quasicrystal-Like System". Modern Physics Letters B 17, n. 15 (30 giugno 2003): 841–45. http://dx.doi.org/10.1142/s0217984903005834.

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By using the thermal Green's function technique, we consider the transport properties in a randomly distributed system of the aggregation that corresponds to the correlated unit-cell configurations, in which the nearest distance between each configuration is ~ 2π/2k F . We introduce the temperature dependence of the conductivity of the quasicrystal-like system.

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17

Garofalo, Anthony. "Housing Electrons: Relating Quantum Numbers, Energy Levels, and Electron Configuration". Journal of Chemical Education 74, n. 6 (giugno 1997): 709. http://dx.doi.org/10.1021/ed074p709.

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18

Prendergast, David, M. Nolan, Claudia Filippi, Stephen Fahy e J. C. Greer. "Impact of electron–electron cusp on configuration interaction energies". Journal of Chemical Physics 115, n. 4 (22 luglio 2001): 1626–34. http://dx.doi.org/10.1063/1.1383585.

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19

Makarenko, L. F., S. B. Lastovskii, E. Gaubas, Je A. Pavlov, M. Moll, H. S. Yakushevich e L. I. Murin. "INJECTION ANNEALING OF THE SELF DI-INTERSTITIAL – OXYGEN COMPLEX IN p-TYPE SILICON". Proceedings of the National Academy of Sciences of Belarus. Physics and Mathematics Series 54, n. 2 (1 luglio 2018): 220–28. http://dx.doi.org/10.29235/1561-2430-2018-54-2-220-228.

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With the use of deep level transient spectroscopy (DLTS) the effect of injection of minority charge carriers (electrons) on an annealing rate of self di-interstitial – oxygen (I2O) complex in silicon has been studied. The complex has been formed by irradiation of epitaxial boron-doped n+–p diode structures with alpha-particles at room temperature. It has been shown that the disappearance of this complex at room temperature begins at a direct current density of ~1.5 A/cm2. This characteristic current density has been found for 10 W·cm p-type silicon when the total radiation defect density was less than 15 % of the initial boron concentration, a divalent hole trap with energy levels of Ev + 0.43 eV and Ev + 0.54 eV has been found to appear as a result of recombination-enhanced annealing of the I2O. When the I2O complex is annealed thermally, the concurrent appearance of an electron trap with an energy level of Ec – 0.35 eV has been observed. It has been shown that the divalent hole trap represents a metastable configuration (BH-configuration) of the bistable defect, whereas the electron trap is stab le in the p-Si configuration (ME-configuration). From the comparison of DLTS signals related to different defect configurations it is found that the ME-configuration of this bistable defect can be characterized as a center with negative correlation energy. It has been shown that the injection-stimulated processes make it very difficult to obtain reliable data on the formation kinetics of the bistable defect in the BH-configuration when studying the thermal annealing of the I2O complex.

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Hansen, S. B. "Configuration interaction in statistically complete hybrid-structure atomic models1This article is part of a Special Issue on the 10th International Colloquium on Atomic Spectra and Oscillator Strengths for Astrophysical and Laboratory Plasmas." Canadian Journal of Physics 89, n. 5 (maggio 2011): 633–38. http://dx.doi.org/10.1139/p11-006.

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Configuration interaction can have significant effects on the transition energies and strengths of diagnostically important X-ray emission lines and features. However, including full configuration interaction (CI) effects by computing extensive collections of fine structure (LS term) levels may be computationally prohibitive for complex ions. In this paper, we show that CI effects in a simple ion vary little with the configuration of spectator electrons, and that CI effects in complex ions are fairly consistent from one ionization stage to the next, particularly for highly charged ions. Therefore, we argue that the CI effects within an ion can be approximated by extending the CI effects computed from a small subset of configurations in that ion to all transitions of the type (nlj)–(nlj)′ in that ion, regardless of the spectator electron. This approach to CI enforces consistency between the fine structure and averaged states in hybrid-structure atomic models, which are designed to provide a computationally efficient balance of spectroscopic accuracy and statistical completeness.

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21

Sen, K. D., P. C. Schmidt e Alarich Weiss. "Sternheimer Antishielding Functions ß(r) and γ(r) for Rare Earth Atoms". Zeitschrift für Naturforschung A 41, n. 1-2 (1 febbraio 1986): 37–46. http://dx.doi.org/10.1515/zna-1986-1-208.

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The Sternheimer shielding-antishielding functions ß(r) and γ(r) are reported for all the fourteen lanthanide atoms at the uncoupled Hartree-Fock level of theory. Each atom is considered in two valence state configurations, 4fn 5d0 and 4 fn-1 5d1, and the nonrelativistic HF wave functions have been used. The 5d1 configuration leads to a smaller net antishielding than the 4fn configuration by ~ 6-12% in the series. The electron-electron self consistency effects are found to be less than 5% in the series. The importance of the calculated antishielding functions in the antishielding theory of electric field gradients in noncubic metals is discussed.

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22

Liang, W. Y. "A Model for Correlated Valence Fluctuation in High Tc Superconductors". International Journal of Modern Physics B 01, n. 03n04 (agosto 1987): 1049–55. http://dx.doi.org/10.1142/s0217979287001547.

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A simple model is proposed as a possible mechanism for high T c superconductivity in certain copper oxides based on correlated valence fluctuation. Electron pairs are formed by Coulomb attraction between electrons in mainly Cu2+ ( d 9 configuration) pyramidal planes mediated by Cu 3+ ( d 8 configuration) ions in the CuO 4 chain-like plane in YBa2Cu3O7−x . These electron pairs have high binding energies necessary for high Tc , and the model is capable of explaining a number of other observed properties.

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23

Harcourt, Richard D. "Increased Valence or Electronic Hypervalence for Symmetrical Three-Centre Molecular Orbital Configurations". Australian Journal of Chemistry 60, n. 9 (2007): 691. http://dx.doi.org/10.1071/ch07189.

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With ψ1 = y + k1a + b, ψ2 = y – b, and ψ3 = y – k3a + b as Y–A and A–B bonding, non-bonding, and antibonding three-centre molecular orbitals for a symmetrical Y–A–B type bonding unit with overlapping atomic orbitals y, a, and b, it is deduced that the maximum value for the A atom valence, (VA = Vab + Vay), is (a) 4(3 – 2√2) = 0.6863 for the one-electron and five-electron configurations Φ(1) = (ψ1)1 and Φ(5) = (ψ1)2ψ2)2(ψ3)1; (b) 8(3 – 2√2) = 1.3726 for the two-electron and four-electron configurations Φ(2) = (ψ1)2 and Φ(4) = (ψ1)2(ψ2)2; and (c) 4/3 for the three-electron configuration Φ(3) = (ψ1)2(ψ2)1. Thus for each of the three-centre molecular orbital configurations, the A-atom can exhibit increased valence, or electronic hypervalence, relative to the valence for an A-atom in a two-centre molecular orbital configuration. When k1 ≠ 0 for Φ(1) and k3 ≠ 0 for Φ(5), the A-atom odd-electron charge is not equal to zero. This odd-electron charge is available for (fractional) electron-pair bonding to a fourth atom X, to give an additional contribution, Va, to the valence. The resulting maximum value for the A-atom valence (VA = Vab + Vay + Va) is equal to 1.2020 for each of Φ(1) and Φ(5). A-atom valencies are calculated for the three-centre bonding units for several molecules and ions. The expressions for VA = Vab + Vay were derived with atomic orbital overlap integrals omitted. The present paper shows how the theory is modified when these integrals are included.

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Bianconi, A., A. Clozza, A. Congiu Castellano, S. Della Longa, M. De Santis, A. Di Cicco, K. Garg et al. "EXPERIMENTAL EVIDENCE OF ITINERANT Cu 3d9 - OXYGEN HOLE MANY BODY CONFIGURATION IN THE HIGH-TC SUPERCONDUCTOR YBa2Cu3O~7". International Journal of Modern Physics B 01, n. 03n04 (agosto 1987): 853–62. http://dx.doi.org/10.1142/s0217979287001213.

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Cu L3 x-ray absorption near edge structure (XANES) and Cu L 3 x-ray photoelectron spectroscopy (XPS) of YBa2Cu3O6.5+x are compared. The breakdown of one-electron picture of its electronic structure is reported. The data are interpreted by mixing of Cu 3d9 and of [Formula: see text] (where [Formula: see text] is a hole in the oxygen derived band, ligand hole) many body configuration in the initial state. The localization of Cu 3d9 configuration is indicated by the bare Coulomb interaction Udd~6 eV . The conductivity is assigned to the itinerant [Formula: see text] configuration. The experimental evidence that the additional oxygen x, giving higher Tc , increases the weight of the [Formula: see text] configuration is reported. The presence of holes on the oxygen atoms is confirmed by the Ols XPS spectra. The Cu3+(Cu 3d8) configuration is not observed in L3 XANES in agreement with valence band XPS giving the energy of the 3d8 excited state at about 12 eV above the ground state. An energy scheme of the many body configurations in YBa2Cu3O~7 is obtained. These experiments give experimental evidence that the high Tc superconductivity is due to pairing of holes in the oxygen valence band interacting with localized electrons at the Cu sites.

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Ruterana, P., A. Béré e G. Nouet. "Formation and stability of the prismatic stacking faultin wurtzite (Al,Ga,In) nitrides". MRS Internet Journal of Nitride Semiconductor Research 5, S1 (2000): 266–72. http://dx.doi.org/10.1557/s1092578300004373.

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The formation of the {1 10} stacking fault, which has two atomic configurations in wurtzite (Ga,Al,In)N, has been investigated by high resolution electron microscopy and energetic calculations. It originates from steps at the SiC surface and it can form on a flat (0001) sapphire surface. A modified Stillinger-Weber potential was used in order to investigate the relative stability of the two atomic configurations. They have comparable energy in AlN, whereas the 1/2<10 1>{1 10} configuration is more stable in GaN and InN. In GaN layers, only the 1/2<10 1>{1 10} configuration was observed. The 1/6<20 3> configuration was found in small areas inside the AlN buffer layer where it folded rapidly to the basal plane, and when back into the prismatic plane, it took the 1/2<10 1>{1 10} atomic configuration.

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Nitescu, Andrei, Cristina Besleaga, George Alexandru Nemnes e Ioana Pintilie. "Bistable Boron-Related Defect Associated with the Acceptor Removal Process in Irradiated p-Type Silicon—Electronic Properties of Configurational Transformations". Sensors 23, n. 12 (19 giugno 2023): 5725. http://dx.doi.org/10.3390/s23125725.

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The acceptor removal process is the most detrimental effect encountered in irradiated boron-doped silicon. This process is caused by a radiation-induced boron-containing donor (BCD) defect with bistable properties that are reflected in the electrical measurements performed in usual ambient laboratory conditions. In this work, the electronic properties of the BCD defect in its two different configurations (A and B) and the kinetics behind transformations are determined from the variations in the capacitance-voltage characteristics in the 243–308 K temperature range. The changes in the depletion voltage are consistent with the variations in the BCD defect concentration in the A configuration, as measured with the thermally stimulated current technique. The A→B transformation takes place in non-equilibrium conditions when free carriers in excess are injected into the device. B→A reverse transformation occurs when the non-equilibrium free carriers are removed. Energy barriers of 0.36 eV and 0.94 eV are determined for the A→B and B→A configurational transformations, respectively. The determined transformation rates indicate that the defect conversions are accompanied by electron capture for the A→B conversion and by electron emission for the B→A transformation. A configuration coordinate diagram of the BCD defect transformations is proposed.

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Xu, Min, Gang Jiang, Miao Wu, Xiangfu Li, Guojie Bian e Feng Hu. "Multiconfiguration Dirac–Fock calculations of excitation energies and wavelengths in highly charged tungsten ions". Canadian Journal of Physics 94, n. 6 (giugno 2016): 563–68. http://dx.doi.org/10.1139/cjp-2015-0772.

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The fully relativistic multiconfiguration Dirac–Fock (MCDF) method is employed to calculate the excitation energies and wavelengths for nine isoelectronic sequences of tungsten ions. In calculations, electron correlations, quantum electrodynamical (QED) effect, and Breit correction are taken into account. The core–valence and valence–valence corrections are analyzed in a systematic way. The core setting was systematically studied for four cases of one electron occupying the outermost s orbital, one electron occupying the outermost p orbital, three electrons occupying the outermost p orbital, and one electron occupying the outermost d orbital. In our research, at least two calculation models are adopted for every tungsten ion. Through analyzing our results, it is found that the following three calculation models can help to get results closer to measured values: (i) setting the closed shells as core; (ii) taking core–valence corrections into account when there is only one valence electron; (iii) taking valence–valence corrections into account when the number of valence electrons is not less than three. The purpose of this paper is to provide some references on configuration selection and configuration interaction in calculations for a multi-electron system of highly charged tungsten ions.

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Peysson, Y., e J. Decker. "Fast electron bremsstrahlung in axisymmetric magnetic configuration". Physics of Plasmas 15, n. 9 (settembre 2008): 092509. http://dx.doi.org/10.1063/1.2981391.

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Grenda, Stanley C. "A simple mnemonic device for electron configuration". Journal of Chemical Education 65, n. 8 (agosto 1988): 697. http://dx.doi.org/10.1021/ed065p697.

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Bang, Jens N., e Henrik Georg Bohr. "Current functional theory for multi-electron configuration". Theoretical Chemistry Accounts 125, n. 3-6 (30 settembre 2009): 555–68. http://dx.doi.org/10.1007/s00214-009-0640-y.

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Eliav, Ephraim, Uzi Kaldor, Peter Schwerdtfeger, Bernd A. Hess e Yasuyuki Ishikawa. "Ground State Electron Configuration of Element 111". Physical Review Letters 73, n. 24 (12 dicembre 1994): 3203–6. http://dx.doi.org/10.1103/physrevlett.73.3203.

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Nest, M. "The multi-configuration electron–nuclear dynamics method". Chemical Physics Letters 472, n. 4-6 (aprile 2009): 171–74. http://dx.doi.org/10.1016/j.cplett.2009.03.013.

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33

Jonauskas, Valdas. "Electron-impact single ionization of Si+". Astronomy & Astrophysics 642 (ottobre 2020): A185. http://dx.doi.org/10.1051/0004-6361/202038266.

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Electron-impact single ionization is studied in the Si+ ion by considering transitions among energy levels. The study includes excitation-autoionization (EA) and collisional ionization processes. The excitations are investigated up to shells with the principal quantum numbers n ≤ 10. It is shown that correlation effects included in the EA calculations play a crucial role in explaining measurements. The correlation effects diminish the EA cross sections by ∼30% compared to single-configuration calculations. However, the collisional ionization is not significantly affected by an extension of the basis of interacting configurations. Good agreement between the presented level-to-level distorted wave data and experimental measurements is found for the single ionization of the Si+ ion.

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34

UNNIKRISHNAN, C. S., e C. P. SAFVAN. "EXPERIMENTAL TEST OF A QUANTUM-LIKE THEORY: MOTION OF ELECTRONS IN A UNIFORM MAGNETIC FIELD, IN A VARIABLE POTENTIAL WELL". Modern Physics Letters A 14, n. 07 (7 marzo 1999): 479–90. http://dx.doi.org/10.1142/s0217732399000535.

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We describe an experiment to test a quantum-like theory which predicts quantum-like behavior for an ensemble of electrons in a classical configuration with static magnetic and electric fields. Some of the earlier experiments had supporting evidence for anomalous, quantum-like effects in such a situation showing systematic modulations of electron current when a retarding potential is varied, even though the quantum wavelength of the electrons in such a configuration was less than a billionth of the spatial width of the potential well. Our experiment conclusively rules out any nonclassical, quantum-like behavior in electron transmission through simple electric barriers, when magnetic fields are present. We identify secondary electrons generated at various electrodes as the main source of apparent anomalous behavior. We also present a classical derivation of the quantum-like equation describing the modulations.

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35

MAKSYM, PETER A., RYOTARO ARITA e HIDEO AOKI. "SPIN CONFIGURATION IN THE ELECTRON MOLECULE IN FEW-ELECTRON QUANTUM DOTS IN STRONG MAGNETIC FIELDS — SUPERPOSITION OF MULTIPLE CONFIGURATIONS". International Journal of Modern Physics B 21, n. 08n09 (10 aprile 2007): 1643–48. http://dx.doi.org/10.1142/s021797920704335x.

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Electron correlation in molecular quantum dot states is examined with an exact dot model and a Hubbard model. The orbital and spin angular momentum of a 5-electron dot in the ν < 1 regime are consistent with the occurrence of a superposition 4- and 5-fold configurations. Hubbard model correlation functions are calculated for these configurations. Spin summed pair correlation functions agree well with the exact results but there are differences in the spin resolved functions.

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36

Kynienė, Aušra, Sigitas Kučas, Šarūnas Masys e Valdas Jonauskas. "Electron-impact ionization of Fe8+". Astronomy & Astrophysics 624 (aprile 2019): A14. http://dx.doi.org/10.1051/0004-6361/201833762.

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Electron-impact ionization cross sections and Maxwellian rate coefficients are presented for the Fe8+ion by considering processes from the ground and metastable levels. The lifetimes of the levels for the 3s23p53d configuration were analysed using the extended basis of interacting configurations. Convergence of the cross sections for the indirect process due to excitations to the high-nlsubshells was investigated. We demonstrate that excitations to the subshells with orbital quantum numberl = 3 with subsequent autoionization dominate up to electron energies of ∼700 eV for the ground and metastable levels. Modelling of theoretical cross sections obtained for the ground and metastable levels to produce the best fit to the measurements shows that 15% of ions reach the reaction zone in the metastable state. The obtained results contradict the previous work that showed ∼30% for the metastable fraction.

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37

Roth, Ilan. "Energetic Solar Electrons – Whistler Bootstrap, Magnetic Knots and Small-scale Reconnection". Proceedings of the International Astronomical Union 6, S274 (settembre 2010): 178–81. http://dx.doi.org/10.1017/s1743921311006879.

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AbstractThe (near) relativistic electrons, emanating from the solar corona in long-lasting, gradual events, are generally observed at 1 AU as delayed vs the less energetic, type-III beams. The observations are consistent with the delayed electrons being energized along the stretched post-CME coronal field lines, when the tail of an anisotropic seed population, which is injected in conjunction to the observed radioheliograph bursts, interacts with the self-excited whistler waves (bootstrap mechanism). These bursts indicate efficient processes where suprathermal seed electrons are injected as a result of magnetic reconnection at the marginally stable coronal configuration left behind the emerging CME. The dependence of the bootstrap mechanism on the electron injection raises the general question of the MHD description and its deviation over the small electron skin-depth scale. The similarity between MHD and knot theories allows one to characterize any turbulent magnetic configuration through topological invariants, while deviation over electron skin-depth scale, characterized by the generalized vorticity, which is enhanced due to density inhomogeneity, creates the conditions for the potential injection sites.

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38

Abdul kader A. Hassan, Fareed M. Mohammed, Sameh H. Salih e Shalash A. Mohammed. "A study of electron momentum density in Ti_Al system." Tikrit Journal of Pure Science 23, n. 4 (5 agosto 2018): 96–101. http://dx.doi.org/10.25130/tjps.v23i4.529.

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We present the electron momentum densities of TiAl , Ti3Al and TiAl3 alloys in terms of Compton profile. Compton profiles (CP) of Ti and Al metals were calculated by adopting the renormalized free atom (RFA) and free electron models and choosing (3d3 – 4s1) configuration to Ti and (3s2 – 3p1) to Al as best electron configurations. The Compton profiles values were obtained by the Superposition model for the three intermetallic alloys. The theoretical results were compared with the experimental values. The present work results of TiAl , Ti3Al and TiAl3 alloys are in good agreement with the experimental values.

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CHEN, KE-QIU, BEN-YUAN GU, YU-KAE LIN e D. S. CHUU. "TRANSMISSION PROPERTIES OF ELECTRONS IN A T-TYPE OPENED QUANTUM WAVEGUIDE WITH INHOMOGENEOUS MAGNETIC FIELDS". International Journal of Modern Physics B 13, n. 08 (30 marzo 1999): 903–15. http://dx.doi.org/10.1142/s0217979299000758.

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We calculate the quantum-mechanical transmission of electrons in a T-shaped opened quantum waveguide (TOQW) subjected to an inhomogeneous magnetic field perpendicular to the TOQW plane with the use of the mode-matching technique. An electron incident through one branch of the waveguide can travel into the other two channels in the quantum ballistic regime. We find that transmission coefficients in two channels exhibit quite difference from each other and depend sensitively on geometric parameters and magnetic configurations. Sharp peaks with unity amplitude and deep dips are observed in transmission spectrum as a function of the Fermi energy of the incident electrons at some high fields. We also study the variation of transmission with magnetic field and find that the transmission exhibits various patterns such as step drop, deep dips, wide valley, large oscillations, or without any structure, sensitively depending on the incident electron energy and magnetic confinement configurations. It is expected that by applying inhomogeneous magnetic fields to the TOQW with appropriate magnetic configuration one may provide an available way to control transmission property of the TOQW to match practical requirements in devices.

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40

Epping, Brian, Michael Rapp, Devin Barry, Adam Daskalakis, Yaron Danon, Ezekiel Blain, Peter Brand et al. "Measurement of Photoneutron Yields Using the RPI LINAC and Assessment of Evaluated Photoneutron Data for Tantalum and Beryllium". EPJ Web of Conferences 284 (2023): 01019. http://dx.doi.org/10.1051/epjconf/202328401019.

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A new experiment configuration was designed, developed, and implemented to measure photoneutron yields using the Rensselaer Polytechnic Institute (RPI) electron linear accelerator (LINAC) at the RPI Gaerttner LINAC Center. The experiment configuration includes a new target assembly that converts the LINAC electron beam into a high energy bremsstrahlung photon flux incident upon a sample material of interest. The photons excite nuclei in the sample of interest, which can subsequently emit neutrons (photoneutrons). The photoneutrons emitted in the direction of the detector system travel through a series of collimated vacuum pipes before reaching a pair of proton-recoil high-energy neutron detectors. The signals generated by the neutron detectors are processed using a digital data acquisition system and subsequently analyzed to determine the energy-dependent photoneutron yield from the sample of interest. The new experiment configuration was used to perform proof-of-concept experiments to measure the photoneutron yields from samples of tantalum and beryllium. The measured results were then compared against the results from Monte Carlo simulations of the detailed experiment configurations to perform preliminary assessments of evaluated photoneutron data libraries.

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41

He, R. J., Z. Wang, H. S. Fu, J. B. Cao, Y. Y. Liu e Z. Z. Guo. "Characteristics of Electron Pitch-angle Distribution in the Flapping Magnetotail". Astrophysical Journal 940, n. 2 (24 novembre 2022): 99. http://dx.doi.org/10.3847/1538-4357/ac9669.

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Abstract The configuration, local motions, and related physics processes of the terrestrial magnetotail have been well studied, playing a key role in magnetotail dynamics. But characteristics of electron pitch-angle distribution (PAD), and the formation mechanisms, at different regions in the flapping magnetotail were not pointed out. Here, we study a current sheet crossing event detected by the Magnetospheric Multiscale Mission inside a magnetotail, and investigate the electron PAD of the event in detail. When the spacecraft are out of the current sheet, low-energy and high-energy electrons present field-aligned PAD and cigar-type PAD, respectively. This difference shows different motions of electrons. We proposed two possible explanation mechanisms: crossing a newly dipolarized magnetotail, or crossing the exhaust region of the reconnection region, and we discussed them in the paper adequately. Based on the dipolarized mechanism, for the first time, we point out that bouncing electrons could be the indicator of a newly dipolarized magnetotail. In addition, four other current sheet crossing cases with similar signatures are observed. Our study improves the understanding of current sheet dynamics and magnetotail configuration physics.

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42

Hanurjaya, Stephanus, Miftahul Anwar, Meiyanto Eko Sulistyo, Irwan Iftadi e Subuh Pramono. "Analysis of Triple Quantum Dots Single Electron Transistor (TQD-SET) for Various Configuration". Journal of Electrical, Electronic, Information, and Communication Technology 2, n. 2 (30 ottobre 2020): 56. http://dx.doi.org/10.20961/jeeict.2.2.44840.

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<p class="Abstract">Single electron transistor (SET) has high potential for the development of quantum computing technologies in order to provide low power consumption electronics. For that purpose, many studies have been conducted to develop SET using dopants as quantum dots (QD). The working principle of SET basically is a single electron tunneling one by one through tunnel junction based on the coulomb blockade effect. This research will simulate various configurations of triple quantum dots single electron transistors (TQD-SET) using SIMON 2.0 with an experimental approach of MOSFET with dopants QD. The configurations used are series, parallel, and triangle configuration. The mutual capacitance (Cm), tunnel junctions (TJ), and temperature values of TQD-SET configurations are varied. The I-V characteristics are observed and analyzed for typical source-drain voltage (Vsd). it is found that the TQD series requires larger Vsd than parallel or triangular TQDs. On the other hands, the current in parallel TQD tends to be stable even though Cm is changed, and the current in the TQD triangle is strongly influenced by the Cm. By comparing these three configurations, it is observed that the tunnelling rate is higher for parallel TQD due to higher probability current moves through three dots by applying Vds.</p>

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43

Dorward, D. W. "A Low Cost Configuration for Internetwork Telemicroscopy". Microscopy and Microanalysis 6, S2 (agosto 2000): 1146–47. http://dx.doi.org/10.1017/s1431927600038228.

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Advances in internetwork data transmission rates and reductions in the cost of imaging components and applications have facilitated real-time sharing of video, still images, and microscope operating systems with collaborators or observers at remote locations. Specialized direct and web-based systems for transmission electron microscopy have been described previously. However, in order to develop a generic and flexible means of sharing live images and data from light, scanning electron, and transmission electron microscope instruments, a telemicroscopy system was configured using readily available components and software that can be adapted for use with most common computer operating and networking systems.Figure 1 diagrams the general configuration used in our laboratory. Input devices can include inexpensive desktop digital or analog video cameras, specialized fast or slow scan CCD cameras, and the analog video-screen signal generated by scanning electron microscopes. For transmission through TCP/IP networks, analog signals must be digitized with a frame grabber card.

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44

Angadi, Gangadhar, Hebbale NarayanaRao Narasimha Murthy, Sridhar Ramakrishna, Salim Firdosh, Raghavendra Nagappa e Krishna Munishamaiah. "Effect of screw configuration on the dispersion of nanofillers in thermoset polymers". Journal of Polymer Engineering 37, n. 8 (26 ottobre 2017): 815–25. http://dx.doi.org/10.1515/polyeng-2015-0427.

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Abstract This paper deals with the study of screw configuration for dispersing nanofillers in thermoset polymers using an intermesh co-rotating twin screw extruder. The influence of kneading elements on the dispersion of nanoclay in epoxy was examined using 10 different screw configurations. Nanoclay was dispersed in epoxy at a barrel temperature of 5°C and a screw speed of 100 rpm. The combination of right hand kneading block and three/four lobed kneading blocks resulted in uniform dispersion of nanofiller. Positive staggered angle with right hand kneading elements yielded uniform dispersion of the nanofiller. Mechanical properties of epoxy nanocomposites processed with these configurations were better than those of neat epoxy. Excessive shear was associated with four lobed kneading block (4KB)/4KB configuration and hence degradation of polymers leading to shorter chains, whereas inadequate shearing in neutral kneading block (NKB)/NKB configuration led to agglomerations. These observations were evidenced by scanning electron microscopy (SEM) and X-ray diffraction (XRD).

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45

Kirschbaum, Rolf W., Markus Hausmann, Olga V. Boltalina, Steven H. Strauss e Thomas Drewello. "Energy-dependent gas-phase fragmentation of fluorofullerene multiply charged anions (MCAs)". Physical Chemistry Chemical Physics 17, n. 35 (2015): 23052–58. http://dx.doi.org/10.1039/c5cp03112e.

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The fragmentation behavior of fluorofullerene di- and trianions is governed by their electronic stability. Ions with the less stable odd-electron configuration dissociate into species with the more stable even-electron configuration.

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46

Shindo, Daisuke, Shinji Aizawa, Zentaro Akase, Toshiaki Tanigaki, Yasukazu Murakami e Hyun Soon Park. "Electron Holographic Visualization of Collective Motion of Electrons Through Electric Field Variation". Microscopy and Microanalysis 20, n. 4 (12 maggio 2014): 1015–21. http://dx.doi.org/10.1017/s1431927614000786.

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AbstractThis study demonstrates the accumulation of electron-induced secondary electrons by utilizing a simple geometrical configuration of two branches of a charged insulating biomaterial. The collective motion of these secondary electrons between the branches has been visualized by analyzing the reconstructed amplitude images obtained using in situ electron holography. In order to understand the collective motion of secondary electrons, the trajectories of these electrons around the branches have also been simulated by taking into account the electric field around the charged branches on the basis of Maxwell’s equations.

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47

Hembree, Gary G., Frank C. H. Luo e John A. Venables. "Auger electron spectroscopy and microscopy in STEM". Proceedings, annual meeting, Electron Microscopy Society of America 49 (agosto 1991): 464–65. http://dx.doi.org/10.1017/s0424820100086623.

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Spatial resolution in Auger electron spectroscopy (AES) is primarily a function of the excitation beam current distribution. For highest resolution the question of how to produce such a small probe of electrons is coupled with how to extract the secondary electrons efficiently from the sample. Kniit and Venables have shown the optimum configuration for highest resolution AES is a combination of a magnetic immersion lens, additional solenoids (“parallelizers“) to shape the weak magnetic field in the low energy electron transport region and a concentric hemispherical analyzer (CHA) to disperse and detect the secondary electrons. This combination has been incorporated into a new ultra-high vacuum STEM at ASU, along with the low energy electron optics required to interface the magnetic collection system with the CHA.

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48

Heo, Jiyoung. "Calculation of Vertical Detachment Energies for Bromochlorobenzene Dimer Anions: Dependence of Substitution Position^#". Bulletin of the Korean Chemical Society 36, n. 3 (20 febbraio 2015): 925–29. http://dx.doi.org/10.1002/bkcs.10173.

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The structure and energetics of neutral and anionic dimer configurations for three bromochlorobenzene (BCB) isomers were investigated with the quantum mechanical calculations on the level of M06‐2X/6‐311++G(d, p). The neutral dimers within 5 kcal/mol of the relative energy had the parallel‐displaced configurations for all isomers. The structures of dimer anions were obtained from these low‐energy neutral configurations, and four, two, and one configurations (relative energy < 5 kcal/mol) were found in o‐BCB, m‐BCB, and p‐BCB dimer anions, respectively. The electron was attached mainly to one of the Br atoms in o‐BCB and m‐BCB cases, and therefore the calculated vertical electron detachment energies (VDEs) were similar to the electron affinity of the atomic Br. However, the p‐BCB dimer anion had the sandwiched configuration and the negative charge was delocalized, showing the relatively small VDE value. The calculated VDE for p‐BCB agreed reasonably well with the experimental one.

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Persson, Ingmar. "Hydrated metal ions in aqueous solution: How regular are their structures?" Pure and Applied Chemistry 82, n. 10 (6 agosto 2010): 1901–17. http://dx.doi.org/10.1351/pac-con-09-10-22.

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The hydration reaction is defined as the transfer of an ion or neutral chemical species from the gaseous phase into water, Mn+(g) → Mn+(aq). In this process, water molecules bind to metal ions through ion-dipole bonds of mainly electrostatic character. The hydration reaction is always strongly exothermic with increasing heat of hydration with increasing charge density of the ion. The structures of the hydrated metal ions in aqueous solution display a variety of configurations depending on the size and electronic properties of the metal ion. The basic configurations of hydrated metal ions in aqueous solution are tetrahedral, octahedral, square antiprismatic, and tricapped trigonal prismatic. This paper gives an overview of the structures of hydrated metal ions in aqueous solution with special emphasis on those with a non-regular coordination figure. Metal ions without d-electrons in the valance shell form regular aqua complexes with a coordination figure, allowing a maximum number of water molecules to be clustered around the metal ion. This number is dependent on the ratio of the metal ion radius to the atomic radius of oxygen in a coordinated water molecule (1.34 Å). The lighter lanthanoid(III) ions have a regular tricapped trigonal prismatic configuration with the M–O distance to the capping water molecules somewhat longer than to the prismatic ones. However, with increasing atomic number of the lanthanoid(III) ions, an increasing distortion of the capping water molecules is observed, resulting in a partial loss of water molecules in the capping positions for the heaviest lanthanoids. Metal ions with d4 and d9 valance shell electron configuration, as chromium(II) and copper(II), respectively, have Jahn–Teller distorted aqua complexes. Metal ions with low charge and ability to form strong covalent bonds, as silver(I), mercury(II), palladium(II), and platinum(II), often display distorted coordination figures due to the second-order Jahn–Teller effect. Metal ions with d10s2 valence shell electron configuration may have a stereochemically active lone electron pair (hemi-directed complexes) or an inactive one (holo-directed). The hydrated tin(II), lead(II), and thallium(I) ions are hemi-directed in aqueous solution, while the hydrated bismuth(III) ion is holo-directed. The structures of the hydrated cationic oxo-metal ions are reported as well.

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Et. al., G. E. Adesakin ,. "Vibrational Internal Energy And Helmholtz Free Energy Of Metals". Turkish Journal of Computer and Mathematics Education (TURCOMAT) 12, n. 10 (28 aprile 2021): 7638–48. http://dx.doi.org/10.17762/turcomat.v12i10.5673.

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This article revealed an interesting issue on vibrational internal energy and Helmholtz free energy of metals. The relationship existing between the lateral strain and axial strain was taking into consideration during computation. Vibrational internal energy and Helmholtz free energy of metals was computed and studied based on the theory of free electron approximation using the knowledge of thermodynamic potentials. Computed and theoretically obtained experimental valueof vibrational internal energy and Helmholtz free energy of metals agreed quite well with each other.Vibrational internal energy of metals increases as temperature increasesdue to change in atomic configuration mode and valence electron exchange between ions in metals.Increase in vibrational internal energy of metals as strain increases can be caused by weak electron cohesion and uncertainties regarding the behavior of valence electrons, atomic size, atomic configuration and bonding interaction between the electron in metals. Result obtained for free energy of metals is negative throughout which indicate that there is a better binding between electron in metals. Free energy of metals decreases as temperature increases due to reduction in atomic interaction and bond strength between the interacting electron in metals. Free energy of metals decreases as strain increases.

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