Structural and thermomechanical properties of the zinc-blende AlX (X = P, As, Sb) compounds

2017 ◽  
Vol 31 (21) ◽  
pp. 1750141
Author(s):  
Vu Thi Thanh Ha ◽  
Vu Van Hung ◽  
Pham Thi Minh Hanh ◽  
Viet Tuyen Nguyen ◽  
Ho Khac Hieu
Keyword(s):  
Elastic Moduli ◽  
Systematic Approach ◽  
Nearest Neighbor ◽  
Mean Square Displacement ◽  
Quantum Statistical Mechanics ◽  
Thermomechanical Properties ◽  
Ambient Conditions ◽  
Zinc Blende ◽  
Properties Of Materials ◽  
Analytical Expressions

The structural and thermomechanical properties of zinc-blende aluminum class of III–V compounds have been studied based on the statistical moment method (SMM) in quantum statistical mechanics. Within the SMM scheme, we derived the analytical expressions of the nearest-neighbor distance, thermal expansion coefficient, atomic mean-square displacement and elastic moduli (Young’s modulus, bulk modulus and shear modulus). Numerical calculations have been performed for zinc-blende AlX (X = As, P, Sb) at ambient conditions up to the temperature of 1000 K. Our results are in good and reasonable agreements with earlier measurements and can provide useful references for future experimental and theoretical works. This research presents a systematic approach to investigate the thermodynamic and mechanical properties of materials.

STUDY OF THERMODYNAMIC PROPERTIES OF ZINC-BLENDE-TYPE SEMICONDUCTORS: TEMPERATURE AND PRESSURE DEPENDENCES

2011 ◽  
Vol 25 (12n13) ◽  
pp. 1041-1051 ◽  
Author(s):  
HO KHAC HIEU ◽  
VU VAN HUNG
Keyword(s):  
Nearest Neighbor ◽  
Thermodynamic Quantities ◽  
Atomic Displacements ◽  
Zinc Blende ◽  
The Mean ◽  
Temperature And Pressure ◽  
Analytical Expressions ◽  
Theoretical Results ◽  
Nearest Neighbor Distances ◽  
Statistical Moment Method

Using the statistical moment method (SMM), the temperature and pressure dependences of thermodynamic quantities of zinc-blende-type semiconductors have been investigated. The analytical expressions of the nearest-neighbor distances, the change of volumes and the mean-square atomic displacements (MSDs) have been derived. Numerical calculations have been performed for a series of zinc-blende-type semiconductors: GaAs , GaP , GaSb , InAs , InP and InSb . The agreement between our calculations and both earlier other theoretical results and experimental data is a support for our new theory in investigating the temperature and pressure dependences of thermodynamic quantities of semiconductors.

scholarly journals Thermodynamic properties of semiconductor compounds studied based on Debye-Waller factors

Open Physics ◽  
2015 ◽  
Vol 13 (1) ◽  
Author(s):  
Nguyen Van Hung ◽  
Nguyen Cong Toan ◽  
Nguyen Ba Duc ◽  
Dinh Quoc Vuong
Keyword(s):  
Thermodynamic Properties ◽  
Mean Square Displacement ◽  
Close Relation ◽  
Relative Displacement ◽  
Mean Square ◽  
Many Body ◽  
Zinc Blende ◽  
Semiconductor Compounds ◽  
The Mean ◽  
Analytical Expressions

AbstractThermodynamic properties of semiconductor compounds have been studied based on Debye-Waller factors (DWFs) described by the mean square displacement (MSD) which has close relation with the mean square relative displacement (MSRD). Their analytical expressions have been derived based on the statistical moment method (SMM) and the empirical many-body Stillinger-Weber potentials. Numerical results for the MSDs of GaAs, GaP, InP, InSb, which have zinc-blende structure, are found to be in reasonable agreement with experiment and other theories. This paper shows that an elements value for MSD is dependent on the binary semiconductor compound within which it resides.

Elastic Moduli and Elastic Constants of Alloy AuCuSi With FCC Structure Under Pressure

2019 ◽  
Vol 38 (2019) ◽  
pp. 264-272 ◽  
Author(s):  
Nguyen Quang Hoc ◽  
Bui Duc Tinh ◽  
Nguyen Duc Hien
Keyword(s):  
Elastic Constants ◽  
Elastic Moduli ◽  
Nearest Neighbor ◽  
Young Modulus ◽  
Numerical Results ◽  
Main Metal ◽  
Substitution Alloy ◽  
Rigidity Modulus ◽  
The Mean ◽  
Fcc Structure

AbstractThis paper studies on the dependence of the mean nearest neighbor distance, the Young modulus E, the bulk modulus K, the rigidity modulus G and the elastic constants C11, C12, C44 on temperature, pressure, the concentration of substitution atoms and the concentration of interstitial atoms for alloy AuCuSi (substitution alloy AuCu with interstitial atom Si) with FCC structure by the way of the statistical moment method (SMM). The numerical results for alloy AuCuSi are compared with the numerical results for main metal Au, substitution alloy AuCu, interstitial alloy AuSi, other calculated results and experiments.

Functionalization of Bipyrenol: Potential Precursors for Advanced Chiral Molecules

Synthesis ◽  
2020 ◽  
Vol 52 (22) ◽  
pp. 3452-3460
Author(s):  
Ken-ichi Sugiura ◽  
Umme Aiman Liza
Keyword(s):  
Functional Group ◽  
Chiral Molecules ◽  
High Quantum Yield ◽  
Ambient Conditions ◽  
Circularly Polarized ◽  
Circularly Polarized Luminescence ◽  
Polarized Luminescence ◽  
Properties Of Materials ◽  
Chiral Materials ◽  
Widespread Interest

Considering the widespread interest in the chiroptical properties of materials, especially circularly polarized luminescence (CPL), the functionalization of bipyrenol (BPy) was carried out aiming at future advanced chiral materials (ACMs) in which BPy shows a high quantum yield and clear CPL spectra. To create ACMs using BPy units that contain nucleophilic substituents, amine and thiol were selected as the functional group and attached to BPy by means of alkyl linkages. The obtained thiol and amine derivatives are stable under ambient conditions. To demonstrate the potential of these molecules, photoinduced electron-transfer systems were synthesized.

THE FIRST-PRINCIPLES STABILITY STUDY OF PdC AND CdC COMPOUNDS

2013 ◽  
Vol 27 (06) ◽  
pp. 1350016
Author(s):  
ENGIN ATESER ◽  
HAVVA BOGAZ OZISIK ◽  
ENGIN DELIGOZ ◽  
KEMAL COLAKOGLU
Keyword(s):  
First Principles ◽  
Elastic Moduli ◽  
Stability Study ◽  
Correlation Effects ◽  
Generalized Gradient ◽  
Shear Moduli ◽  
Exchange Correlation ◽  
Zinc Blende ◽  
Debye Temperatures ◽  
Stable Structures

We have studied structural, mechanical and dynamical properties of PdC and CdC compounds to predict the most stable structure. We have focused on seven binary structure types as rock salt (RS), caesium chloride ( CsCl ), zinc blende (ZB), wurtzite (WZ), tungsten carbide (WC), cadmium telluride ( CdTe ) and nickel arsenide ( NiAs ). For modelling exchange-correlation effects we have used generalized gradient (GGA) approximation based on Perdew–Burke–Ernzhorf functional (PBE). The polycrystalline elastic moduli such as Young's and shear moduli, Poisson's ratio, sound velocities, Debye temperatures and shear anisotropic factors have been presented for mechanically stable structures using second-order elastic constants calculated from the stress-strain relations. The results show that PdC is thermodynamically, mechanically and dynamically stable in ZB structure. On the other hand, while CdC is energetically in favor of RS structure, it is mechanically and dynamically stable in ZB structure.

Vibrational and Elastic Properties of Bulk Metallic Glass: Application to Pd64Fe16P20

2016 ◽  
Vol 1141 ◽  
pp. 91-95 ◽  
Author(s):  
Payal N. Chauhan ◽  
Chaudhari Prakruti ◽  
R.H. Joshi ◽  
Nisarg K. Bhatt ◽  
Brijmohan Y. Thakore
Keyword(s):  
Metallic Glass ◽  
Bulk Metallic Glass ◽  
Elastic Properties ◽  
Elastic Moduli ◽  
Nearest Neighbor ◽  
Phonon Dispersion ◽  
Phonon Dispersion Curve ◽  
The Core ◽  
Realistic Assumption ◽  
Model Pseudopotential

Different elastic properties of Pd-based Pd64Fe16P20 have been computed using two different forms of pseudopotential. Both the forms differ within the core region suggesting different degrees of orthogonalization and its r-dependence, while outside the core both preserves the Columbic nature. The only parameter, the core radius, separates these regions, and it is calculated using the realistic assumption based on the nearest neighbor distance. Further, five different forms of the local field correlated functions, namely, Hartree (H), Taylor (T), Ichimaru and Utsumi (IU), Farid et al. (F) and Sarkar et al. (S) are examined for better understanding regarding the screening effect on different elastic constants for Pd64Fe16P20 bulk metallic glass. The calculated results for the various elastic moduli, Poisson's ratio, sound velocity and phonon dispersion curve are all found to be in general agreement with the available experimental data. This confirms the applicability of the model pseudopotential to bulk metallic systems.

scholarly journals On the Turns of Digital Images

2015 ◽  
Vol 20 (2) ◽  
pp. 157-165
Author(s):  
P. G. Parfenov
Keyword(s):  
Nearest Neighbor ◽  
Hexagonal Lattice ◽  
Rectangular Lattice ◽  
Characteristic Set ◽  
Arbitrary Angle ◽  
Characteristic Sets ◽  
Predicted Values ◽  
Analytical Expressions ◽  
Eulerian Characteristic ◽  
Good Agreement

The images built on the basis of rectangular and hexagonal lattices are discussed in the article. For images on a rectangular lattice a formula is proposed, which gives approximate values of the components of a characteristic set of coefficients when turning at an arbitrary angle by the method of the nearest neighbor. The characteristic sets are presented in the form of diagrams, an experimental evaluation of errors is made. It was confirmed a good agreement with the predicted value component of characteristic sets and those which were obtained experimentally. For images built on the basis of a hexagonal lattice was offered a similar formula for the approximation of the components of the characteristic set for rotating at any angle, when this was applied to the modification of the nearest neighbor method for the preservation of coherence, as it was discovered its violation in some cases on a hexagonal lattice. On the basis of four-pixel fragments are built diagrams, which show a good agreement of predicted values and the obtained ones in the experiment. It was defined a system of three-pixel hexagonal fragments to which the theorem is proved on the Eulerian characteristic and were offered analytical expressions, which allow to avoid experimental detection of the characteristic sets of coefficients for all possible reference angles. Their use requires to produce only one such experiment.

scholarly journals High-temperature effect on the material constants and elastic moduli for solid rocks

2021 ◽  
Vol 18 (4) ◽  
pp. 583-593
Author(s):  
Jian Yang ◽  
Li-Yun Fu ◽  
Bo-Ye Fu ◽  
Zhiwei Wang ◽  
Wanting Hou
Keyword(s):  
Temperature Dependence ◽  
High Temperatures ◽  
Elastic Moduli ◽  
Constitutive Relations ◽  
Thermomechanical Properties ◽  
Linear Temperature Dependence ◽  
Free Energy Function ◽  
Linear Temperature ◽  
Material Constants ◽  
Geologic Materials

Abstract Thermally coupled constitutive relations are generally used to determine material constants and elastic moduli (Young's modulus and shear modulus) of solid media. Conventional studies on this issue are mainly based on the linear temperature dependence of elastic moduli, whereas analytical difficulties are often encountered in theoretical studies on nonlinear temperature dependence, particularly at high temperatures. This study investigates the thermally coupled constitutive relations for elastic moduli and material constants using the assumption of axisymmetric fields, with applications to geologic materials (marble, limestone and granite). The Taylor power series of the Helmholtz free energy function within dimensionless temperatures could be used to develop the thermally coupled constitutive relations. The thermoelastic equivalent constitutive equations were formulated under the generalized Hooke's law. The material constants of solid rocks were determined by fitting experimental data using axisymmetric stress and strain fields at different temperatures, based on their thermomechanical properties. For these geologic materials, the resultant equivalent elastic moduli and deformations were in good agreement with those from the experimental measurements. Thermal stresses, internal moisture evaporation and internal rock compositions significantly affected the experimental results. This study provides a profound understanding of the thermally coupled constitutive relations that are associated with the thermomechanical properties of solid rocks exposed to high temperatures.

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