Scholarlink

<p>Rare-earths dicarbides REC<sub>2</sub> (RE = Ce, Pr, Nd, Sm, Gd and Dy) in CaC<sub>2</sub>-type structure are investigated through density functional theory (DFT). The understudy dicarbides are highly correlated electron systems because of the 4f orbital of RE atoms. To treat these systems, exchange correlation functional generalized gradient approximation along with Hubbard U (GGA + U) is utilized. The phonon spectra confirm the dynamic stability of these carbides and the calculated lattice parameters are found to be in closed agreement with the existing experimental data. The magnetic ground state optimization energies demonstrate that all these carbides are stable in antiferromagnetic (AFM) phase. The electron charge density plots and electronegativity difference on Pauling scale confirm the covalent between rare-earth ion (RE<sup>+ 3</sup>) and acetylide ion C<sub>2</sub>. All of these carbides’ electronic properties in the AFM phase reveal their metallic nature. The ductility of all these intermetallics is revealed by the elastic parameters. All these carbides possess intermediate Vickers’s hardness confirming their moderately hard nature. Based on the physical properties of these dicarbides like moderate hardness, high temperature strength and metallic nature it is expected that they could be considered as a suitable candidate for high temperature applications provided they are adequately shielded from atmospheric moisture.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Theoretical Analysis of the Rare-Earth Dicarbides REC2 (RE = Ce, Pr, Nd, Sm, Gd and Dy), in CaC2-Structure

  • 期刊论文

  • 发表日期：

    2026年7月21日

查看全文
  • Safi Ullah,
  • Zahid Ali,
  • Israr Ahmad,
  • Saif Ullah,
  • Hamad Ali,
  • Mazhar Ali

摘要

Rare-earths dicarbides REC2 (RE = Ce, Pr, Nd, Sm, Gd and Dy) in CaC2-type structure are investigated through density functional theory (DFT). The understudy dicarbides are highly correlated electron systems because of the 4f orbital of RE atoms. To treat these systems, exchange correlation functional generalized gradient approximation along with Hubbard U (GGA + U) is utilized. The phonon spectra confirm the dynamic stability of these carbides and the calculated lattice parameters are found to be in closed agreement with the existing experimental data. The magnetic ground state optimization energies demonstrate that all these carbides are stable in antiferromagnetic (AFM) phase. The electron charge density plots and electronegativity difference on Pauling scale confirm the covalent between rare-earth ion (RE+ 3) and acetylide ion C2. All of these carbides’ electronic properties in the AFM phase reveal their metallic nature. The ductility of all these intermetallics is revealed by the elastic parameters. All these carbides possess intermediate Vickers’s hardness confirming their moderately hard nature. Based on the physical properties of these dicarbides like moderate hardness, high temperature strength and metallic nature it is expected that they could be considered as a suitable candidate for high temperature applications provided they are adequately shielded from atmospheric moisture.