Theoretical Characterization of Thermodynamic, Magnetic and Electronic Proprieties of Full-Heusler Co2YGa (Y = V, Cr and Mn) Alloys

SPIN ◽  
2020 ◽  
Vol 10 (01) ◽  
pp. 2050005
Author(s):  
M. Mokhtari ◽  
D. Amari ◽  
F. Dahmane ◽  
G. Benabdellah ◽  
L. Zekri ◽  
...  

The electronic structure, magnetism and thermal proprieties of the full-Heusler alloys Co2YGa (Y [Formula: see text] V, Cr and Mn) have been investigated by first-principles calculations based on density functional theory with the generalized gradient approximation (GGA). Our obtained results of lattice parameters show reasonable agreement to the previously reported experimental and other theoretical studies. The calculations show that all Co2YGa (Y [Formula: see text] V, Cr and Mn) alloys belong to half-metallic compound with a magnetic moment of 2.00, 3.00 and 4.00 [Formula: see text] at their respective equilibrium lattice constants which is in good agreement with the Slater–Pauling rule and perfect 100% spin polarization at the Fermi level. The thermal effect on the macroscopic properties of these alloys is presented such as the thermal expansion coefficient, heat capacity and Debye temperature, based on the quasi-harmonic Debye model.

2021 ◽  
Vol 24 (1) ◽  
pp. 13703
Author(s):  
S. Zeffane ◽  
M. Sayah ◽  
F. Dahmane ◽  
M. Mokhtari ◽  
L. Zekri ◽  
...  

We investigate the structural, electronic and magnetic properties of the full Heusler compounds Mn2YSn (Y = Mo, Nb, Zr) by first- principles density functional theory using the generalized gradient approximation. It is found that the calculated lattice constants are in good agreement with the theoretical values. We observe that the Cu2MnAl-type structure is more stable than the Hg2CuTi type. The calculated total magnetic moments of Mn2NbSn and Mn2ZrSn are 1 μB and 2 μB at the equilibrium lattice constant of 6.18 Å and 6.31 Å, respectively, for the Cu2MnAl-type structure. Mn2MoSn have a metallic character in both Hg2CuTi and Cu2MnAl type structures. The total spin magnetic moment obeys the Slater-Pauling rule. Half-metal exhibits 100% spin polarization at the Fermi level. Thus, these alloys are promising magnetic candidates in spintronic devices.


Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 2057 ◽  
Author(s):  
Areej Shawahni ◽  
Mohammed Abu-Jafar ◽  
Raed Jaradat ◽  
Tarik Ouahrani ◽  
Rabah Khenata ◽  
...  

The structural, mechanical, electronic and optical properties of SrTMO3 (TM = Rh, Zr) compounds are investigated by using first principle calculations based on density functional theory (DFT). The exchange-correlation potential was treated with the generalized gradient approximation (GGA) for the structural properties. Moreover, the modified Becke-Johnson (mBJ) approximation was also employed for the electronic properties. The calculated lattice constants are in good agreement with the available experimental and theoretical results. The elastic constants and their derived moduli reveal that SrRhO3 is ductile and SrZrO3 is brittle in nature. The band structure and the density of states calculations with mBJ-GGA predict a metallic nature for SrRhO3 and an insulating behavior for SrZrO3. The optical properties reveal that both SrRhO3 and SrZrO3 are suitable as wave reflectance compounds in the whole spectrum for SrRhO3 and in the far ultraviolet region (FUV) for SrZrO3.


2015 ◽  
Vol 29 (31) ◽  
pp. 1550229 ◽  
Author(s):  
M. Khalfa ◽  
H. Khachai ◽  
F. Chiker ◽  
N. Baki ◽  
K. Bougherara ◽  
...  

The electronic structure, mechanical and thermodynamic properties of Fe2VX, (with X = Al and Ga), have been studied self consistently by employing state-of-the-art full-potential linearized approach of augmented plane wave plus local orbitals (FP-LAPW + lo) method. The exchange-correlation potential is treated with the local density and generalized gradient approximations (LDA and GGA). Our predicted ground state properties such as lattice constants, bulk modulus and elastic constants appear more accurate when we employed the GGA rather than the LDA, and these results are in very good agreement with the available experimental and theoretical data. Further, thermodynamic properties of Fe2VAl and Fe2VGa are predicted with pressure and temperature in the ranges of 0–40 GPa and 0–1500 K using the quasi-harmonic Debye model. We have obtained successfully the variations of the heat capacities, primitive cell volume and volume expansion coefficient.


2016 ◽  
Vol 30 (01) ◽  
pp. 1550265 ◽  
Author(s):  
F. Dahmane ◽  
D. Mesri ◽  
A. Tadjer ◽  
R. Khenata ◽  
S. Benalia ◽  
...  

The structural, electronic as well as the magnetic properties of the Co2CrX (X[Formula: see text]Al, Ga and In) full-Heusler alloy have been studied using first-principles calculations performed in the framework of density functional theory (DFT) within the generalized gradient approximation (GGA). It was taken into account both possible L21 structures (i.e. Hg2CuTi- and Cu2MnAl-type). Basically, for all compounds, the Cu2MnAl-type structure is energetically more stable than Hg2CuTi-type structure at the equilibrium volume. The electronic structure calculations for Co2CrAl reveal that half-metallic (HM) character in Cu2MnAl-type structure, Co2CrGa show nearly HM behavior and Co2CrIn has a metallic character. The predicted total magnetic moment is [Formula: see text] for Co2CrX (X[Formula: see text]Al, Ga) which is in good convergence with the Slater–Pauling (SP) rule.


2020 ◽  
Vol 66 (5 Sept-Oct) ◽  
pp. 604
Author(s):  
M. Berber ◽  
N. Bouzouira ◽  
H. Abid ◽  
A. Boudali ◽  
H. Moujri

In this study, we have investigated the structural, electronic, and magnetic properties of the Rb2NaVF6 compound. We have performed our calculations by the use of first-principle methods based on spin-polarized density functional theory, where the electronic exchange-correlation potential is treated by the generalized gradient approximation GGA- PBEsol coupled with the improved TB-mBJ approach. The calculated structural parameters of Rb2NaVF6 are in good agreement with the available experimental data. Rb2NaVF6 exhibits a half-metallic ferromagnetic feature with a spin polarization of 100 % at the Fermi level and a direct large half-metallic gap of 3.582 eV. The total magnetic moments are 2 μB. This material is half-metallic ferromagnets, and it can be potential candidates for spintronics applications at a higher temperature.


2012 ◽  
Vol 571 ◽  
pp. 292-295
Author(s):  
Ben Hai Yu ◽  
Chao Xu ◽  
Dong Chen

We report ab initio calculations of the structural, elastic and optical properties of the compound LaB6 as a function of pressure. The computation is based on the density functional theory in combination with the generalized gradient approximation functional. The calculated lattice constants and elastic moduli are compared with the theoretical results and a good agreement is found. LaB6 can retain its mechanical stability in the pressure range of 0-20GPa. Besides, the frequency-dependent dielectric function, absorption coefficient and loss function of LaB6 are also obtained. The calculated static dielectric function is 8.8 at 0GPa and 5GPa. The computed results should be testified by experiments.


Author(s):  
S. Belhachi ◽  
S. Amari

We have investigated the electronic and magnetic properties of the doped Heusler alloys Cu2Cr[Formula: see text]V[Formula: see text]Ga ([Formula: see text], 0.5, and 1) using first-principles density functional theory within the generalized gradient approximation scheme. Lattice constants of all phases were determined, and the absence of energy gap in both the spin channels predicts that the materials are metallic. The calculated formation energies are negative, indicating stability of these compounds. Electronic structure and magnetic behavior are reported for the first time for the Cu2Cr[Formula: see text]V[Formula: see text]Ga alloy. It was found that the alloys are ferromagnetic, and metallic witch is confirmed by GGA[Formula: see text]U calculation.


RSC Advances ◽  
2019 ◽  
Vol 9 (52) ◽  
pp. 30462-30478 ◽  
Author(s):  
Kenji Nawa ◽  
Yoshio Miura

A density functional theory (DFT)+U method based on linear response (LR) theory was applied to investigate the electronic structures of Co-based full Heusler alloys of ternary Co2YSi and quaternary Co2(Y,Mn)Si.


2013 ◽  
Vol 738 ◽  
pp. 22-25
Author(s):  
Chao Xu ◽  
Dong Chen

The structural and elastic properties of the cubic spinel Ge3N4 semiconductor have been investigated using the ab initio scheme within the generalized gradient approximation in the framework of density functional theory. Quantities such as lattice constants and elastic constants of interest are calculated. A good agreement is found between our results and the other data. Through the lattice dynamics, in which the finite displacement method is used, we have obtained successfully the thermal properties such as the phonon curve, free energy, heat capacity and Debye temperature in the whole temperature range from 0 to 1000K. It is the authors ambition that these results will inspire further experimental study on the Ge-based semiconductors. * Corresponding author: CHEN Dong


2012 ◽  
Vol 535-537 ◽  
pp. 1291-1294 ◽  
Author(s):  
Xiu De Yang ◽  
Bo Wu ◽  
Song Zhang

By using generalized gradient approximation (GGA) scheme within the density functional theory (DFT), the electronic and magnetic properties of Hg2CuTi-type Heusler alloy Ti2FeAl were investigated. The results reveal that a 100% spin polarization appears at Fermi level (εF) in Ti2FeAl, and is maintained during lattice range of 5.1Å~6.2Å. Ti2FeAl is one of stable Half-Metallic Ferromagnets (HMF) with a spin-minority gap of 0.5 eV at εF and total magnetic moment of 1μB per unit cell. Our studies also indicate that the competition between RKKY-type indirect exchange and direct hybridization of d-electronic atoms plays a dominating role in determining the magnetism.


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