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We would like to correct some inaccuracies in our previous paper “STRUCTURAL AND THERMODYNAMIC PROPERTIES OF Cu2ZnSnS4 MATERIAL: THEORETICAL PREDICTION”, Annals of West University of Timisoara-Physics, 65 (2023) 160-170. https://doi.org/10.2478/awutp-2023-0012 During the analysis of the data we forget to divide by N (N = 2 is the number of formula units per cell) to transform the unities from Ry/cell/K to J.mol-1.K-1, and from Ry/cell to kJ/mol, respectively. So with consequence, we found that some of our data of the thermodynamic properties are muliplied by 2. In addition, we rectified the unity from kJ N-1mol-1 to kJ/mol.

The present work aims to investigate the structural and thermodynamic properties of homogenous tetragonal Cu2ZnSnS4 (CZTS) absorber material in Kesterite phase using first-principle calculations based on density functional theory (DFT). This approach requires only knowledge of the atomic species and crystal structure to predict several physical properties of materials. The Quantum Espresso code within the Ultra Soft pseudopotentials (USPP) and the local density approximation (LDA) were used in the calculations. Equilibrium unit cell volumes, bulk modulus, as well as the pressure derivative of the bulk modulus are predicted. In addition, several thermodynamic properties, especially: the Debye’s vibrational energy, the vibrational free energy, the vibrational entropy, and the constant volume heat capacity at different temperatures T of Cu2ZnSnS4 material are calculated and discussed. Our study shows that the vibrational energy, the entropy and the constant volume heat capacity increase with increasing temperature, while the vibrational free energy decreases monotonously with the increase of temperature.

In this work, an ab-initio calculation is used to investigate the elastic constants and some other mechanical and thermal parameters of tetragonal Cu2ZnSnS4 (CZTS) quaternary semiconducting bulk material in Kesterite (KS) and Stannite (ST) phases. The Quantum Espresso code within the Ultra Soft pseudo potentials (USPP) and the local density approximation (LDA) approach were used in the calculation. Firstly,, studies are started with the prediction of the elastic stiffness constants Cij and the normal and shear anisotropy factors. Then some other mechanical moduli, especially the isotropic bulk modulus B, the shear modulus G, the Young modulus E, the Poisson’s ratio ν, and the Pugh’s criteria (G/B) are delivered. The analysis of the mechanical stability criteria at equilibrium shows that our elastic stiffness constants Cij of CZTS material obey all the stability conditions. Additionally, some other parameters of the CZTS semiconductor, especially: the Vickers hardness HV, the sound velocity, the Debye temperature θD and the melting temperature Tm were also calculated. The obtained values of the elastic constants Cij and other mechanical and thermal parameters agree well with experimental and other theoretical results of the literature. The Debye temperature θD of the KS phase was found at around 332.7 K, and that of the stannite phase was found equal to 329.1 K, respectively.

The present work aims to predict the elastic constants and other significant properties of ordered BxAl1-xSb (0 ≤ x ≤ 1) ternary semiconducting alloys. We report the initial results of the elastic stiffness constants, the bulk modulus, the aggregate shear modulus, the Cauchy ratio, the aggregate Young’s modulus, the Born ratio, the isotropy factor, the fracture toughness and the longitudinal, transverse and average sound velocities. The Debye temperature and the melting point were also predicted using two different empirical expressions. Except the Cauchy ratio, which decreases with enhancing boron content x, all other physical quantities of BxAl1-xSb alloys increase gradually and monotonically with increasing of boron concentration x in the range 0-1.

Based on a home-made Monte Carlo simulation, the electron backscattering coefficient, mean penetration depth, transmission probability, and transmission energy distribution of 1-5 keV electron normally incident penetrating in indium thin film targets have been computed. The trend of all features of interest as a function of the indium film thickness at both nanometric scale region and bulk material region has been examined and discussed. The present predictions may be seen as the first investigation regarding 1-5 keV electrons impinging on indium thin film targets. Copyright © 2016 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper deals with on-line real coded genetic algorithms optimization based on vector control for loss minimization operation of induction motor Losses minimization is obtained by adjusting the magnetizing current component with respect to the torque current component to give minimum total copper and iron losses. Some simulation results are obtained by using both online real code genetic algorithm optimization and minimal function which use the derivative of the total losses of the motor. Those results are compared with the field-oriented control method without optimization. Results show that the efficiency of induction motor can be improved under different operational conditions especially in light load region. [ABSTRACT FROM AUTHOR]