Search

Search Results

• First principle investigation of physical properties of MNiBi: (M = Sc, Y) half-Heusler compounds

  MISSOUM Djamel-Eddine, Kaddour BENCHERIF, Djilali BENSAID

  061601 1–11

  2022-11-01

  Abstract:

  We have investigated the half Heusler compounds MNiBi (M=Sc, Y), using the framework of density functional theory DFT within the full potential linearized augmented plane wave (FP-LAPW) method and studied the structural, electronic, optical and elastic properties. The structural properties are predicted using the Generalized Gradient Approximation GGA and Local Density Approximation LDA, the calculations reveal that Lattice constants and other structural parameter are better matched in GGA approximation with experimental and theoretical result than LDA approximation. The calculated band structure and the density of states (DOS) with GGA, LDA and Tran and Blaha modified Becke-Johnson (TB-mBJ) exchange-correlation potentials, indicates a semiconducting nature with indirect narrow band gaps for both compounds ScNiBi and YNiBi, it shown from result that using (TB-mBJ) functionals is much more successful than the LDA and GGA approach in estimating bandgaps for our half Heusler ScNiBi and YNiBi. Optical properties of the compounds under investigation are also reported in this paper, high absorptivity are observed in the visible and ultraviolet region. The bulk modulus, shear modulus, young’s modulus, and other elastic constants are computed to discuss their elastic properties.

  ⬇️ Scroll down to see the full summary

  DOI: https://doi.org/10.31349/RevMexFis.68.061601

• Half-metallic and thermodynamic properties of new d 0 CsCaZ (Z= Ge, Sn and Pb) half Heusler alloys: A spin-based devices vision for the future

  Fatima Bendahma, M. Mana, M. Hammou, S. Terkhi, N. Benderdouche, S. Bentata

  061004 1–12

  2022-11-01

  Abstract:

  Density functional theory (DFT) was applied to investigate the structural, electronic, elastic, magnetic, thermodynamic and half-metallic properties of the newly d⁰ Heusler alloys (HAs) CsCaZ (Z= Ge, Sn and Pb). Spin-polarised calculations show that  the compounds studied are half-metallic with a magnetic moment of 1.00 μB at the equilibrium lattice parameter, which obeys the well-known Slater–Pauling rule M_tot = 8 – Zt. The half-metallic behavior of the compounds CsCaGe, CsCaSn and CsCaPb is predicted with respect to the equilibrium lattice constants for CsCaGe, CsCaSn and CsCaPb with a narrow band gap in the majority spin channel. Furthermore, the elastic constants (Cij) showed that these materials are ductile and anisotropic. In addition, the negative values of the calculated formation energy and cohesion energy indicate that CsCaZ (Z= Ge, Sn and Pb) are likely to be experimentally synthesized. Non-equilibrium Gibbs function is employed to calculate the thermodynamic properties through the quasi-harmonic Debye model in which the bulk modulus, heat capacity, Debye temperature, thermal expansion coefficient, and entropy are investigated at 0-20 Gpa pressure and 0-1200 K temperature ranges. The significant half-metallic behavior makes the CsCaZ (Z= Ge, Sn and Pb) compounds strong candidates for spintronic applications.

  ⬇️ Scroll down to see the full summary

  DOI: https://doi.org/10.31349/RevMexFis.68.061004
• 

  FrYBi (Y = Ca, Sr, Ba) Semiconductors for Visible-Light Harvesting: A multifunctional platform for energy conversion and optoelectronic applications

  O. Hammadache, M. Houari, S. Mesbah, K. Khelifa-Kerfa, M. Benghanem, T. Lantri, B. Belarbi

  1-10

  2026-07-01

  Abstract:

  This study presents a comprehensive first-principles investigation of the structural, electronic, optical, elastic, and thermoelectric properties of the novel half-Heusler compounds FrYBi (Y = Ca, Sr, Ba). Employing density functional theory (DFT) with both the GGA-PBE and mBJ-GGA approximations, we determine that these compounds crystallise in the cubic Clb structure and exhibit indirect band gaps ranging from 0.97 to 1.35 eV, confirming their semiconducting nature. Detailed optical analyses reveal high absorption coefficients, pronounced reflectivity, and favourable dielectric responses within the visible spectrum, indicating potential for optoelectronic applications. Calculations of the elastic properties demonstrate that all compounds are mechanically stable and exhibit ductile behaviour. Thermoelectric analysis indicates high Seebeck coefficients alongside good electrical conductivity, particularly at low to moderate temperatures, suggesting promising performance for energy conversion applications. These findings position FrYBi alloys as compelling candidates for next-generation thermoelectric and optoelectronic devices.

  ⬇️ Scroll down to see the full summary

  DOI: https://doi.org/10.31349/RevMexFis.72.040502