The stacking of antifluorite Fe₂P₂ layer on the electronic structure of the ternary compounds CaFe₂P₂, BaFe₂P₂ and EuFe₂P₂

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• 作者：S. Soliman ^{salma@zu.edu.eg" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Ab initio calculations ; Intermetallic compounds ; Electronic structure ; Fermi surface
• 刊名：Computational Materials Science
• 出版年：2016
• 出版时间：September 2016
• 年：2016
• 卷：122
• 期：Complete
• 页码：177-182
• 全文大小：1536 K

文摘

This work reports a first-principle calculations as a comparative study of the electronic structural properties of the three related tetragonal compounds EuFe₂P₂, BaFe₂P₂ and CaFe₂P₂. The main trends of electronic band structure, density of states, and Fermi surface for the three compounds have been studied. The conventional cell mode contains two Fe–P layers; one at 0.375 and the other at 0.625 on the [0 0 1] axis, enclosing a layer of the rare-earth or alkaline earth atom at 0.5 (the origin is located at 237ad6676a31828ea9f46" title="Click to view the MathML source">4/mmm$4/\mathit{mmm}$). It has been found that the replacement of Eu by either Ba or Ca produces a critical change in the magnetic properties. The calculations showed that the anion replacement of Eu →$\to$ Ba →$\to$ Ca has changed the interlayer spacing which has affected the electronic charge density and the magnetic moment. The resulted magnetic moment of the three compound EuFe₂P₂, BaFe₂P₂ and CaFe₂P₂ is 6.78, 0.0 and 1.2 μ_B${\mathrm{\mu }}_B$ respectively. The study of the three compounds has showed that the spin–orbit coupling in 4f compound EuFe₂P₂, with heavy Eu element, has a higher effect than the crystal field and vice versa in BaFe₂P₂ and CaFe₂P₂. The topology of the Fermi surface is mainly determined by the dispersion of Fe-d and P-p states, which explains the lack of either superconductivity or magnetic order of Fe in these compounds.