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Abstract <p>To investigate the structural, electronic, elastic, and dynamical properties of the VSnPt, NbSnPt, and TaSnPt compounds, density functional theory (DFT) calculations were performed within the generalized gradient approximation (GGA). The calculated lattice parameters, bulk moduli, and their pressure derivatives were systematically analyzed and compared with available theoretical data. The computed cohesive energies and heats of formation exhibited negative values, confirming that the investigated alloys are both structurally and thermodynamically stable. These results suggest that the compounds may be synthesized under equilibrium experimental conditions. All calculated elastic constants satisfy the mechanical stability criteria for cubic crystal systems, confirming the mechanical stability of the investigated materials. In addition, the alloys exhibit ductile behavior together with relatively high melting temperatures. This mechanical robustness indicates that the compounds are not only theoretically stable but may also be suitable for experimental synthesis and practical applications under mechanical stress. The Debye temperatures of VSnPt, NbSnPt, and TaSnPt were also calculated. Among the investigated alloys, VSnPt exhibits the highest Debye temperature, indicating comparatively stronger covalent bonding. Furthermore, the gradual decrease in Debye temperature from VSnPt to TaSnPt suggests a progressive weakening of covalent interactions across the alloy series. Electronic-structure calculations performed using both GGA and GGA+SOC approaches reveal that VSnPt exhibits half-metallic behavior, whereas NbSnPt and TaSnPt display metallic characteristics. The small differences observed between the GGA and GGA+SOC results indicate that spin–orbit coupling has only a minor influence on the electronic properties of this class of materials. Phonon-dispersion calculations predict dynamical instability for all three compounds according to the CASTEP module in Materials Studio results. However, the VASP code calculations indicate that VSnPt and NbSnPt are dynamically stable. To the best of the authors’ knowledge, this work represents the first theoretical investigation of the NbSnPt and TaSnPt alloys, thereby providing new insights into their physical properties and contributing to the understanding of their potential technological applications.</p> Graphical abstract <p></p>

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First-principles density functional theory study of physical properties of half-Heusler XSnPt compounds (X = V, Nb, and Ta) for high-temperature structural application

  • 期刊论文

  • 发表日期：

    2026年6月18日

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  • B O Mnisi,
  • Ibrahim Omer A Ali,
  • E M Benecha,
  • M M Tibane

摘要

Abstract

To investigate the structural, electronic, elastic, and dynamical properties of the VSnPt, NbSnPt, and TaSnPt compounds, density functional theory (DFT) calculations were performed within the generalized gradient approximation (GGA). The calculated lattice parameters, bulk moduli, and their pressure derivatives were systematically analyzed and compared with available theoretical data. The computed cohesive energies and heats of formation exhibited negative values, confirming that the investigated alloys are both structurally and thermodynamically stable. These results suggest that the compounds may be synthesized under equilibrium experimental conditions. All calculated elastic constants satisfy the mechanical stability criteria for cubic crystal systems, confirming the mechanical stability of the investigated materials. In addition, the alloys exhibit ductile behavior together with relatively high melting temperatures. This mechanical robustness indicates that the compounds are not only theoretically stable but may also be suitable for experimental synthesis and practical applications under mechanical stress. The Debye temperatures of VSnPt, NbSnPt, and TaSnPt were also calculated. Among the investigated alloys, VSnPt exhibits the highest Debye temperature, indicating comparatively stronger covalent bonding. Furthermore, the gradual decrease in Debye temperature from VSnPt to TaSnPt suggests a progressive weakening of covalent interactions across the alloy series. Electronic-structure calculations performed using both GGA and GGA+SOC approaches reveal that VSnPt exhibits half-metallic behavior, whereas NbSnPt and TaSnPt display metallic characteristics. The small differences observed between the GGA and GGA+SOC results indicate that spin–orbit coupling has only a minor influence on the electronic properties of this class of materials. Phonon-dispersion calculations predict dynamical instability for all three compounds according to the CASTEP module in Materials Studio results. However, the VASP code calculations indicate that VSnPt and NbSnPt are dynamically stable. To the best of the authors’ knowledge, this work represents the first theoretical investigation of the NbSnPt and TaSnPt alloys, thereby providing new insights into their physical properties and contributing to the understanding of their potential technological applications.

Graphical abstract