Search results

1 – 6 of 6
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 12 April 2018

R. Masrour, M. Ben Ali, H. El Moussaoui, Mohamed Hamedoun, A. Benyoussef and E.K. Hlil

The purpose of this paper is to synthesize the manganese ferrite nanoparticle MnFe2O4 and to investigate the structure, size and to study the electronic and the magnetic…

153

Abstract

Purpose

The purpose of this paper is to synthesize the manganese ferrite nanoparticle MnFe2O4 and to investigate the structure, size and to study the electronic and the magnetic properties of MnFe2O4 nanoparticles.

Design/methodology/approach

The co-precipitation method is used to synthesize the MnFe2O4. The structure and size were investigated by X-ray diffraction. The superconducting quantum interference device is used to determine the some magnetic ground. From theoretical investigation point of view self-consistent ab initio calculations, based on density functional theory approach using full potential linear augmented plane wave method, were performed to investigate both electronic and magnetic properties of the MnFe2O4. The high temperatures series expansion (HTSE) is used to study the magnetic properties of MnFe2O4.

Findings

The saturation magnetization, the coercivity and the transition temperature varied between 21-43 emu/g, 20-50 Oe and 571-630 K, respectively, have been studied. The gap energy of MnFe2O4 has been deduced. The critical temperature and the critical exponent have been obtained using HTSEs.

Originality/value

In the present work, the authors study the electronic and magnetic properties of MnFe2O4. The results obtained by the experiment and by ab initio calculations were used in HTSE as input to deduce other physical parameters.

Details

Multidiscipline Modeling in Materials and Structures, vol. 14 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Access Restricted. View access options
Article
Publication date: 28 July 2021

Maksym Kraiev, Eugene Voronkov and Violeta Kraieva

The purpose is to calculate the change in the total energy of a small fragment of an idealized lattice of iron (in its pure form and with impurity atoms) containing an edge…

43

Abstract

Purpose

The purpose is to calculate the change in the total energy of a small fragment of an idealized lattice of iron (in its pure form and with impurity atoms) containing an edge dislocation during its elementary motion at one interatomic spacing, both under the influence of a constant magnetic field and without it. The introduction of a magnetic field into the system is aimed at checking the adequacy of the description of the phenomenon of magnetoplasticity by changing the total energy of the atomic system.

Design/methodology/approach

The design procedure is based on a quantum-mechanical description of the switching process of the covalent bond of atoms in the dislocation core. The authors used the method of density functional theory in the Kohn-Shem version, implemented in the GAUSSIAN 09 software package. Using the perturbation theory, the authors modeled the impact of an external constant magnetic field on the energy of a system of lattice atoms.

Findings

The simulation results confirmed the effect of an external constant magnetic field on the switching energy of the covalent bond of atoms in the dislocation core, and also a change in the magnetic susceptibility of a system of atoms with a dislocation. This complements the description of the magnetoplastic effect during the deformation of metals.

Originality/value

The authors created quantum-mechanical models of the dislocation motion in the Fe crystal lattice: without impurities, with a substitutional atom Cr and with an interstitial atom C. The models take into account the influence of an external constant magnetic field.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 6
Type: Research Article
ISSN: 1573-6105

Keywords

Access Restricted. View access options
Article
Publication date: 15 December 2020

Samira Idrissi, Soumia Ziti, Hicham Labrim and Lahoucine Bahmad

In this paper, using Monte Carlo simulations (MCSs) under the metropolis algorithm, the authors study the magnetic properties of the yttrium-based Heusler alloys: Y2CrGa and…

129

Abstract

Purpose

In this paper, using Monte Carlo simulations (MCSs) under the metropolis algorithm, the authors study the magnetic properties of the yttrium-based Heusler alloys: Y2CrGa and YFeCrGa. In the first step, the authors elaborate and discuss the ground-state phase diagrams of the more stable configurations. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). This leads to modeling of the compound Y2CrGa by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). The results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Design/methodology/approach

In this paper, the authors study the magnetic properties and the critical behavior of the yttrium-based Heusler alloys, Y2CrGa and YFeCrGa, using MCSs under the metropolis algorithm. In the first step, the authors elaborate and discuss the ground-state phase diagrams of the more stable configurations for the both structures at null temperature (T = 0). On the other hand, for non-null temperature (T ≠ 0), the authors investigate the critical behavior of these two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). Hence, the compound Y2CrGa can be modeled by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). Moreover, the results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Findings

The authors elaborate the ground-state phase diagrams of the more stable configurations. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). This leads to modeling of the compound Y2CrGa by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). The results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Research limitations/implications

The authors elaborate the ground-state phase diagrams of the more stable configurations. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). This leads to modeling of the compound Y2CrGa by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). The results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Practical implications

The authors elaborate the ground-state phase diagrams of the more stable configurations. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). This leads to modeling of the compound Y2CrGa by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). The results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Social implications

The authors elaborate the ground-state phase diagrams of the more stable configurations. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). This leads to modeling of the compound Y2CrGa by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). The results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Originality/value

The authors elaborate the ground-state phase diagrams of the more stable configurations. It is worth to note that the full-Heusler alloy Y2CrGa contains only one magnetic atom (Cr), while the quaternary Heusler alloy YFeCrGa has two magnetic atoms (Cr and Fe). This leads to modeling of the compound Y2CrGa by a Hamiltonian containing only one magnetic spin moment (S = 2), while the quaternary Heusler alloy YFeCrGa is modeled by a Hamiltonian containing two magnetic spin moments (Q = 5/2 and s = 2). The results of the study reveal that the critical temperature increases when increasing the reduced crystal field for the two studied compounds. To complete this study, the authors elaborated the hysteresis cycles of the two yttrium-based Heusler alloys: Y2CrGa and YFeCrGa.

Details

Multidiscipline Modeling in Materials and Structures, vol. 17 no. 3
Type: Research Article
ISSN: 1573-6105

Keywords

Access Restricted. View access options
Article
Publication date: 18 March 2020

Rachid Aharrouch, Karima El Kihel, Mohamed Madani, Nabil Hachem, Amer Lafhal and Mohammed El Bouziani

The purpose of this paper is to study the magnetic properties and the hysteresis behavior of a ferrimagnetic cubic Ising nanowire with mixed spins S = 3/2 and S = 5/2 in which the…

82

Abstract

Purpose

The purpose of this paper is to study the magnetic properties and the hysteresis behavior of a ferrimagnetic cubic Ising nanowire with mixed spins S = 3/2 and S = 5/2 in which the atoms are placed alternately.

Design/methodology/approach

In order to investigate the effects of the exchange interactions and crystal field on the magnetic properties and hysteresis behavior of the nanowire, we have used the Monte Carlo simulation. More precisely, we have plotted the thermal variations of the sublattice and total magnetizations for different values of the Hamiltonian parameters, and we have presented the corresponding phase diagrams. In addition, the influence of an external magnetic field is examined by plotting the variations of hysteresis loops with the change of temperature and crystal field.

Findings

All phase transition found in this study are of second-order and the critical temperatures increase linearly with the increase of the exchange interactions. The compensation temperatures appear only for some domains of crystal field D and exchange interaction JB of the sublattice (B). Moreover, when studying the hysteresis behavior, the system can show one or double hysteresis loops.

Originality/value

The authors consider that this research is consistent with the scientific axis of the journal which benefits a great esteem in our country and in the world. In addition, the results are of technological interest.

Details

Multidiscipline Modeling in Materials and Structures, vol. 16 no. 5
Type: Research Article
ISSN: 1573-6105

Keywords

Access Restricted. View access options
Article
Publication date: 7 January 2025

Hayat Hocine, Friha Khelfaoui, Y. Al-Douri, Keltouma Boudia, Fabien Fontaine-Vive, Ouafaa Sadouki, Amel Slamani, Kadda Amara, Mawloud Belabbas, Fadila Belkharroubi and M. Ameri

The mechanical properties, including elastic constants and moduli, indicate the material’s stiffness and stability. Our calculations reveal that CuMg2GaS4 is a direct bandgap…

11

Abstract

Purpose

The mechanical properties, including elastic constants and moduli, indicate the material’s stiffness and stability. Our calculations reveal that CuMg2GaS4 is a direct bandgap semiconductor, 2.18 eV. A detailed analysis of the electronic structure provides an insight into the bonding characteristics and charge distribution within the material.

Design/methodology/approach

This work presents a comprehensive investigation of the structural, electronic, optical, mechanical properties of the CuMg2GaS4 compound using density functional theory (DFT) calculations. Unlike its counterpart CuMg2InS4, which exhibits a tetragonal WS structure, CuMg2GaS4 is found to be an energetically stable in the monoclinic phase.

Findings

The calculated effective masses of electrons (0.38 m0) and holes (1.28 m0) suggest promising charge carrier mobility within the compound. Furthermore, based on the evaluation of electronic structure and optical absorption properties of CuMg2GaS4 in relation with the redox potentials of water, this demonstrates its potential as a promising candidate for efficient photocatalytic water splitting under visible light irradiation. These findings contribute to the understanding of the structural and functional properties of CuMg2GaS4 and pave the way for its potential applications in optoelectronic and energy conversion devices.

Originality/value

The prime novelty is to employ ab initio self-consistent Full-Potential Linearized augmented plane wave + local orbital method (FP-LAPW + lo) and investigate the properties of CuMg2GaS4 of structural, mechanical, thermodynamic stabilities, linear optical response.

Details

Multidiscipline Modeling in Materials and Structures, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1573-6105

Keywords

Access Restricted. View access options
Article
Publication date: 1 August 1923

A.—The following conditions apply to producers only :—

11

Abstract

A.—The following conditions apply to producers only :—

Details

British Food Journal, vol. 25 no. 8
Type: Research Article
ISSN: 0007-070X

1 – 6 of 6
Per page
102050