scholarly journals Анизотропия поверхностной энергии и работы выхода электрона IIВ металлов

2019 ◽  
Vol 89 (2) ◽  
pp. 306
Author(s):  
И.Г. Шебзухова ◽  
Л.П. Арефьева
Keyword(s):  
Experimental Data ◽  
Surface Energy ◽  
Work Function ◽  
Statistical Method ◽  
Electron Work Function ◽  
Method Of Calculation ◽  
Cadmium Zinc ◽  
Good Agreement

AbstractOn the basis of electron-statistical method of calculation of the surface energy of metals, a technique for estimating the electron work function of hexagonal and rhombohedral metallic crystals has been developed. This technique relates surface energy to work function and can thus be applied to estimate the surface energy of crystal faces from experimental data for a work function. Computations have been made for cadmium, zinc, and mercury macrocrystals. The temperature and orientation dependences of both quantities have been constructed. Our results are in good agreement with literature experimental data.

scholarly journals INFLUENCE OF POLYMORPHIC TRANSFORMATIONS ON ANISOTROPY OF THE SURFACE ENERGY AND THE WORK FUNCTION OF THE ELECTRON OF LITHIUM

2021 ◽  
pp. 439-446
Author(s):  
Ирина Гусейновна Шебзухова ◽  
Людмила Павловна Арефьева
Keyword(s):  
Experimental Data ◽  
Surface Layer ◽  
Surface Energy ◽  
Crystal Lattice ◽  
Work Function ◽  
Analytical Relationship ◽  
Polymorphic Transformations ◽  
Calculation Results ◽  
Limiting Temperatures ◽  
Good Agreement

На базе электронно-статистического метода показана связь и проведена оценка поверхностной энергии и работы выхода электрона граней кристаллов лития с учетом дисперсионного, поляризационного и осцилляционного взаимодействия атомов поверхностного слоя. Считалось, что кристаллическая решетка не имеет дефектов. Модифицированы выражения поправок и аналитического соотношения, связывающего работу выхода электрона и поверхностную энергию с учетом типа кристаллической решетки и ориентации граней. Рассчитана работа выхода электрона и поверхностная энергия гладких граней при предельных температурах существования полиморфных фаз лития. Установлено влияние полиморфных превращений и температуры на анизотропию. Температурный коэффициент работы выхода электрона бездефектного кристалла положителен и составляет порядка 0,1-1 мэВ. Результаты расчетов хорошо согласуются с экспериментальными данными для поликристаллов. On the basis of the electronic-statistical method, a relationship is obtained and the surface energy and the work function of the electron of the faces of lithium crystals are estimated, taking into account the dispersion, polarization, and oscillatory interactions of the atoms of the surface layer. It was assumed that the crystal lattice has no defects. The expressions for the corrections and an analytical relationship between the work function of the electron and the surface energy are modified taking into account the type of the crystal lattice and the orientation of the faces. The work function of the electron and the surface energy of smooth faces are calculated at the limiting temperatures of the existence of polymorphic lithium phases. The influence of polymorphic transformations and temperature on the anisotropy is established. The temperature coefficient of the work function of an electron in a defect-free crystal is positive and amounts to about 0,1-1 meV. The calculation results are in good agreement with the experimental data for polycrystals.

Surface properties of rare-earth metals and the effects of their substitutional doping on work function of the W(110) surface

2019 ◽  
Vol 87 (1) ◽  
pp. 11301
Author(s):  
Jian Wang ◽  
Zhijun He ◽  
Jin Nie ◽  
Xiaoxiao Sun ◽  
Yu Han ◽  
...  
Keyword(s):  
Experimental Data ◽  
Rare Earth ◽  
Surface Energy ◽  
Work Function ◽  
First Principles ◽  
Rare Earth Metals ◽  
Thermionic Emission ◽  
First Principles Calculations ◽  
Substitutional Doping ◽  
Good Agreement

The surface energy and work function of rare-earth metals (from La to Lu) are studied by the first principles calculations. The obtained values are in good agreement with available experimental data. Motivated by enhanced thermionic emission performance resulting from low work function, we substitutionally doped the rare-earth atoms on W(110) surface to improve the work function. The results show that rare-earth atoms doping can significantly reduce the work function of the W(110) surface, and Eu, Pr and Nd are the three best candidates for work function reduction.

Crystallographic anisotropy in surface properties of brass and its dependence on the electron work function

2018 ◽  
Vol 51 (6) ◽  
pp. 1715-1720 ◽  
Author(s):  
Liqiu Guo ◽  
Hao Lu ◽  
D. Y. Li ◽  
Q. X. Huang ◽  
Xu Wang ◽  
...  
Keyword(s):  
Surface Energy ◽  
Work Function ◽  
Surface Properties ◽  
Electron Work Function ◽  
Adhesive Force ◽  
Surface Electron ◽  
Crystallographic Anisotropy ◽  
Atomic Force ◽  
Work Functions ◽  
Crystallographic Planes

The crystallographic anisotropy of the electric current or conductance, adhesive force, elastic modulus, and deformation magnitude of alpha brass were investigated through property mapping using an atomic force microscope. Surface electron work functions of differently oriented grains in the brass were also analyzed using atomic force microscopy. The mapped surface properties are closely related to the electron work function; the work function reflects the surface activity, which is itself dependent on the surface energy. The anisotropy of the properties is closely correlated to the in situ measured surface electron work function. It is demonstrated that crystallographic planes with higher electron work functions exhibit lower current, smaller adhesive forces, larger elastic moduli and smaller deformation magnitudes. Efforts are made to understand the relationships by connecting the properties with surface energy and electron work function. The dependence of the properties on crystallographic orientation can be elucidated by considering the surface electron behavior using electron work function as a novel probing parameter.

scholarly journals ESTIMATION OF THE POLARIZATION AND DISPERSION CORRECTIONS TO THE SURFACE ENERGY OF THE FACES OF METAL CRYSTALS

2020 ◽  
pp. 319-325
Author(s):  
Ирина Гусейновна Шебзухова ◽  
Людмила Павловна Арефьева
Keyword(s):  
Experimental Data ◽  
Surface Energy ◽  
Statistical Method ◽  
Dispersion Correction ◽  
Surface Energies ◽  
Polarization Correction

На базе электронно-статистического метода получены выражения и рассчитаны дисперсионная и поляризационная поправки к поверхностной энергии граней кристаллов IA металлов на границе с вакуумом. Обе поправки сильно анизотропны. Дисперсионная поправка увеличивает величину поверхностной энергии граней (от 3 до 23 %), поляризационная - снижает менее, чем на 1%. Учет данных взаимодействий улучшает согласие результатов расчета поверхностной энергии с экспериментальными данными расплавов. On the basis of the electronic statistical method, expressions for the dispersion and polarization corrections to the surface energy of the crystal faces 1A of metals at the boundary with vacuum are obtained and their value are calculated. Both corrections are highly anisotropic. The dispersion correction increases the surface energies of the faces (from 3 to 23 %), the polarization correction reduces them by less than 1%. Taking into account these interactions improves the agreement between the calculated surface energy and the experimental data of the melts.

The effect of an electric field on the surface energy and electron work function of thin films of alkali metal alloys

2002 ◽  
Vol 28 (6) ◽  
pp. 515-516 ◽  
Author(s):  
V. Z. Kanchukoev ◽  
A. Z. Kashezhev ◽  
A. Kh. Mambetov ◽  
V. A. Sozaev
Keyword(s):  
Thin Films ◽  
Surface Energy ◽  
Alkali Metal ◽  
Electric Field ◽  
Work Function ◽  
Electron Work Function ◽  
Metal Alloys

FACE-DEPENDENT WORK FUNCTION DERIVED FROM THE LOCAL POLARIZATION OF PLASMA AND THE IMAGE FORCE ACTION NEAR A METAL SURFACE

1999 ◽  
Vol 13 (29n30) ◽  
pp. 1081-1085 ◽  
Author(s):  
K. F. WOJCIECHOWSKI ◽  
A. KIEJNA ◽  
H. BOGDANÓW
Keyword(s):  
Work Function ◽  
Metal Surface ◽  
Image Force ◽  
Force Action ◽  
Simple Method ◽  
Method Of Calculation ◽  
The Face ◽  
Local Polarization ◽  
Work Functions ◽  
Good Agreement

The concepts of the spontaneous polarization of plasma near the metal surface and of the image force are used to propose a simple method of calculation of the face-dependent work function. The calculated work functions for low index planes of aluminium and sodium are in good agreement with experiment.

scholarly journals ANISOTROPY OF THE SURFACE OF CUBIC BODY-CENTERED CRYSTAL LATTICES

2021 ◽  
Vol 18 (1) ◽  
pp. 9-15
Author(s):  
V.M. Yurov ◽  
Keyword(s):  
Surface Layer ◽  
Surface Energy ◽  
Work Function ◽  
Single Crystals ◽  
Theoretical Calculations ◽  
Experimental Studies ◽  
Electron Work Function ◽  
Fundamental Parameter ◽  
Statistical Calculation ◽  
Crystal Lattices

In the work of Shebzukhova and Arefieva, by the method of electronic-statistical calculation of the anisotropy of the surface energy of metals, a method for estimating the work function of electrons from a metal was determined. The surface energy and electron work function of four main faces of cadmium and zinc crystals and five faces of mercury are estimated. In the work of Bokarev, the anisotropy of the surface energy of single crystals was calculated from the model of coordination melting of crystals. Based on experimental studies and theoretical calculations, it is shown that the model of coordination melting of crystals unambiguously links the physicochemical properties of the surface of single crystals with their crystal structure. In our proposed empirical model, not only the anisotropy is calculated, but also the thickness of the surface layer of the metal. It is shown that the thickness of the surface layer is determined by one fundamental parameter - the molar (atomic) volume, which periodically changes in accordance with the table of D.I. Mendeleev. It is shown in the work that the work function of electrons changes proportionally with a change in the surface energy of the metal. This means that the device we have developed can be used to measure the state of the metal surface and its anisotropy.

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