ELECTROSTATIC ENERGY AND LATTICE VIBRATIONS IN THIN IONIC SLABS

1981 ◽  
Vol 42 (C6) ◽  
pp. C6-341-C6-343
Author(s):  
G. Kanellis ◽  
J. F. Morhange ◽  
M. Balkanski
Keyword(s):  
Electrostatic Energy ◽  
Lattice Vibrations

Effect of energy filtering on micro-diffraction in the SEM

1994 ◽  
Vol 52 ◽  
pp. 604-605
Author(s):  
James F. Mancuso ◽  
Leo A. Fama ◽  
William B. Maxwell ◽  
Jerry L. Lehman ◽  
Hasso Weiland ◽  
...  
Keyword(s):  
Detection Efficiency ◽  
Ccd Camera ◽  
High Gain ◽  
Microchannel Plate ◽  
Electrostatic Energy ◽  
Energy Filtering ◽  
Electron Channelling ◽  
Low Energy Electrons ◽  
Low Sensitivity ◽  
Angular Field Of View

Micro-diffraction based crystallography is essential to the design and development of many classes of ‘crafted materials’. Although the scanning electron microscope can provide crystallographic information with high spatial resolution, its current utility is severely limited by the low sensitivity of existing diffraction techniques (ref: Dingley). Previously, Joy showed that energy filtering increased contrast and pattern visibility in electron channelling. This present paper discribes the effect of energy filtering on EBSP sensitivity and backscattered SEM imaging.The EBSP detector consisted of an electron energy filter, a microchannel plate detector, a phosphor screen, optical coupler, and a slow scan CCD camera. The electrostatic energy filter used in this experiment was constructed as a cone with 5 coaxial electrodes. The angular field-of-view of the filter was approximately 38°. The microchannel plate, which was the initial sensing component, had high gain and had 50% to 80% detection efficiency for the low energy electrons that passed through the retarding field filter.

Improvement of Power Generation in Low Acceleration for Electrostatic Energy Harvester by Using Bipolar Charging Method

2015 ◽  
Vol 135 (9) ◽  
pp. 372-373 ◽  
Author(s):  
Koji Sonoda ◽  
Keidai Minami ◽  
Naoki Miwatani ◽  
Kensuke Kanda ◽  
Takayuki Fujita ◽  
...  
Keyword(s):  
Power Generation ◽  
Energy Harvester ◽  
Electrostatic Energy

The Energy of the Electrostatic Field

2020 ◽  
Vol 67 (1) ◽  
pp. 35-41
Author(s):  
Igor’ P. Popov
Keyword(s):  
Electrostatic Field ◽  
Energy System ◽  
Electrostatic Energy ◽  
Research Purpose ◽  
Target System ◽  
Mathematical Form ◽  
Stored Energy ◽  
Energy Materials ◽  
Modeling And Analysis ◽  
Maximum Work

The work is actual due to the increased role of electrostatic energy in connection with the beginning of mass production of ionistors used in the power supply system of electric vehicles, and the need for the development of theoretical support. (Research purpose) The research purpose is in increasing the correctness of electrostatic calculations that exclude the possibility of obtaining unreliable results in the form of infinite electrostatic energy. (Materials and methods) Authors have used methods of mathematical modeling and analysis, studied the mathematical model as the equivalent of an object that reflects in mathematical form its most important properties, such as the laws that it obeys, and the relationships inherent in its constituent parts. (Results and discussion) Authors have studied the electrostatic field created by a system of two charges of the same name or different names. The article presents calculations for charges located in bodies that have the shape of balls. It was found that the results could be generalized to any form of charged objects. They gave three definitions: first, the total stored energy is the energy of the system or object, equal to the maximum work that the system or object can do if it is given such an opportunity. Second, the conditional realized stored energy is a part of the total stored energy of the system or object, equal to the work that the system or object can produce, limited by a condition that excludes the possibility of the system or object performing the maximum work that the system or object can hypothetically perform. The third is a conditional impossible reserved energy as a part of a complete stored energy system or an object that is equal to the work system or object can do and limited by the condition, which excludes the possibility of making a system or object maximum work that target system or object could hypothetically do. Five theorems were proved. (Conclusions) It was found that the main drawback of the actual potential energy formula is an infinitely large increase in energy at radius tending to 0. The obtained formulas for stored electrostatic energy are devoid of this drawback.

Vibration spectra of mixed crystals Sc(PO4, VO4) and Y(PO4, VO4)

1982 ◽  
Vol 47 (4) ◽  
pp. 1176-1183 ◽  
Author(s):  
Alexander Muck ◽  
Olga Smrčková ◽  
Bohumil Hájek
Keyword(s):  
Infrared Spectra ◽  
Group Analysis ◽  
Point Of View ◽  
Mixed Crystals ◽  
Site Symmetry ◽  
Lattice Vibrations ◽  
Vibration Spectra ◽  
Space Group

Infrared spectra of mixed crystals Sc(PO4, VO4) and Y(PO4, VO4) have been studied from the point of view of group analysis. These systems form substitution mixed crystals in tetragonal space group D194h. The anions having proper symmetry Td or D2d in site symmetry D2d exhibit in spectra lowering of the site symmetry to effective C2 as a result of lattice vibrations of the type T(B2).

Infrared Spectroscopy Characterization of Marine Shells

2001 ◽  
Vol 711 ◽  
Author(s):  
Octavio Gomez-Martinez ◽  
Daniel H. Aguilar ◽  
Patricia Quintana ◽  
Juan J. Alvarado-Gil ◽  
Dalila Aldana ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Infrared Spectroscopy ◽  
Crassostrea Virginica ◽  
Thermal Treatments ◽  
Vibration Modes ◽  
Lattice Vibrations ◽  
Vibration Frequencies ◽  
Mussel Shells ◽  
Carbonate Lattice

ABSTRACTFourier Transform infrared spectroscopy has been employed to study the shells of two kind of mollusks, American oysters (Crassostrea virginica) and mussels (Ischadium recurvum). It is shown that it is possible to distinguish the different calcium carbonate lattice vibrations in each case, mussel shells present aragonite vibration frequencies, and the oyster shells present those corresponding to calcite. The superposition, shift and broadening of the infrared bands are discussed. Changes in the vibration modes due to successive thermal treatments are also reported.

scholarly journals Molecular Dynamics Simulation on the Interaction between Palygorskite Coating and Linear Chain Alkane Base Lubricant

Coatings ◽  
2021 ◽  
Vol 11 (3) ◽  
pp. 286
Author(s):  
Jin Zhang ◽  
Lv Yang ◽  
Yue Wang ◽  
Huaichao Wu ◽  
Jiabin Cai ◽  
...  
Keyword(s):  
Molecular Dynamics ◽  
Structural Changes ◽  
Molecular Diffusion ◽  
Linear Chain ◽  
Interfacial Interaction ◽  
Dynamics Simulation ◽  
Electrostatic Energy ◽  
Experimental Development ◽  
Practical Applications ◽  
Self Diffusion

Molecular dynamics (MD) simulations were conducted to investigate the interactions between a palygorskite coating and linear chain alkanes (dodecane C12, tetradecane C14, hexadecane C16, and octadecane C18), representing base oils in this study. The simulation models were built by placing the alkane molecules on the surface of the palygorskite coating. These systems were annealed and geometrically optimized to obtain the corresponding stable configurations, followed by the analysis of the structural changes occurring during the MD process. The interfacial interaction energies, mean square displacements, and self-diffusion coefficients of the systems were evaluated to characterize the interactions between base lubricant molecules and palygorskite coating. It was found that the alkanes exhibited self-arrangement ability after equilibrium. The interfacial interaction was attractive, and the electrostatic energy was the main component of the binding energy. The chain length of the linear alkanes had a significant impact on the intensity of the interfacial interactions and the molecular diffusion behavior. Moreover, the C12 molecule exhibited higher self-diffusion coefficient values than C14, C16 and C18. Therefore, it could be the best candidate to form an orderliness and stable lubricant film on the surface of the palygorskite coating. The present work provides new insight into the optimization of the structure and composition of coatings and lubricants, which will guide the experimental development of these systems for practical applications.

scholarly journals The Face-to-Face σ-Hole···σ-Hole Stacking Interactions: Structures, Energies, and Nature

Crystals ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 877
Author(s):  
Yu Zhang ◽  
Weizhou Wang
Keyword(s):  
Quantum Chemical ◽  
Noncovalent Interactions ◽  
Electrostatic Energy ◽  
Stacking Interactions ◽  
Energy Component ◽  
Stacking Interaction ◽  
Face To Face ◽  
The Face ◽  
Π Stacking Interaction ◽  
Induction Energy

The existence of the π···π stacking interaction is well-known. Similarly, it is reasonable to assume the existence of the σ-hole···σ-hole stacking interaction. In this work, the structures, energies, and nature of the face-to-face σ-hole···σ-hole stacking interactions in the crystal structures have been investigated in detail by the quantum chemical calculations. The calculated results clearly show that the face-to-face σ-hole···σ-hole stacking interactions exist and have unique properties, although their strengths are not very significant. The energy component analysis reveals that, unlike many other dispersion-dominated noncovalent interactions in which the induction energies always play minor roles for their stabilities, for the face-to-face σ-hole···σ-hole stacking interaction the contribution of the induction energy to the total attractive energy is close to or even larger than that of the electrostatic energy. The structures, energies, and nature of the face-to-face σ-hole···σ-hole stacking interactions confined in small spaces have also been theoretically simulated. One of the important findings is that encapsulation of the complex bound by the face-to-face σ-hole···σ-hole stacking interaction can tune the electronic properties of the container.

scholarly journals A potential all-electronic route to the charge-density-wave phase in monolayer vanadium diselenide

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Matthew J. Trott ◽  
Chris A. Hooley
Keyword(s):  
Charge Density ◽  
Charge Density Wave ◽  
Density Wave ◽  
Transition Metal Dichalcogenides ◽  
Coulomb Repulsion ◽  
Lattice Vibrations ◽  
Heisenberg Exchange ◽  
Low Energies ◽  
Metal Dichalcogenides ◽  
Charge Density Wave Phase

AbstractThe transition metal dichalcogenides offer significant promise for the tunable realisation and application of correlated electronic phases. However, tuning their properties requires an understanding of the physical mechanisms underlying their experimentally observed ordered phases, and in particular the extent to which lattice vibrations are a necessary ingredient. Here we present a potential mechanism for charge-density-wave formation in monolayers of vanadium diselenide in which the key role at low energies is played by a combination of electron–electron interactions and nesting. There is a competition between superconducting and density-wave fluctuations as sections of the Fermi surface are tuned to perfect nesting. This competition leads to charge-density-wave order when the effective Heisenberg exchange interaction is comparable to the effective Coulomb repulsion. When all effective interactions are purely repulsive, it results instead in d-wave superconductivity. We discuss the possible role of lattice vibrations in enhancing the effective Heisenberg exchange during the earlier stages of the renormalisation group flow.

Sign in / Sign up

Export Citation Format

Share Document