Electronic properties of RX₂Al₂₀ (R = La, Ce, Yb, Th, U; X = Ti, V, Cr and Mn) cage compounds

Journal Article · 20 July 2018 · Computational Materials Science

DOI: https://doi.org/10.1016/j.commatsci.2018.06.047 · OSTI ID:1471054

Swatek, Przemysław ^[1]; Kleinert, Maja ^[2]; Wiśniewski, Piotr ^[2]; Kaczorowski, Dariusz ^[2]

---

1. Polish Academy of Sciences, Wroclaw (Poland); Ames Lab. and Iowa State Univ., Ames, IA (United States)
2. Polish Academy of Sciences, Wroclaw (Poland)

Here, non-spin-polarized electronic structures and Fermi surface properties of RX₂Al₂₀ (R = La, Ce, Yb, Th, U; X = Ti, V, Cr, Mn) intermetallic compounds were calculated using the full potential all-electron local orbital (FPLO) approach in the framework of the local density approximation (LDA). Trends of the magnetism are discussed in terms of the characteristics of X-3d bands with a quantitative analysis of the relationship between band electron filling and crystal electric field splitting. Since coordination icosahedra of X-atoms have small trigonal distortion, crystal electric field splits the fivefold degenerate X-3d state into low-energy singlet and two higher-energy doublets e_g. In RTi₂Al₂₀ and RV₂Al₂₀ the population of the related 3d sub-band is not sufficient to cause energetically favorable spin polarization, whereas magnetic instabilities develop in the RCr₂Al₂₀ series. Finally, a manifestation of strong repulsive interactions between itinerant Mn-d electrons become most pronounced in ferromagnetic UMn₂Al₂₀. The influence of non-magnetic R-f states on magnetic and thermodynamic properties is discussed with special emphasis on the role of the f–p and f–d hybridization. For LaTi₂Al₂₀ and LaV₂Al₂₀ the calculated quantum oscillation frequencies are in accord with experimental reports.

• Research Organization: Ames Laboratory (AMES), Ames, IA (United States)
• Sponsoring Organization: USDOE Office of Science (SC), Basic Energy Sciences (BES)
• Grant/Contract Number: AC02-07CH11358
• OSTI ID: 1471054
• Alternate ID(s): OSTI ID: 1702205
• Report Number(s): IS-J-9739; PII: S0927025618304269
• Journal Information: Computational Materials Science, Vol. 153, Issue C; ISSN 0927-0256
• Publisher: ElsevierCopyright Statement
• Country of Publication: United States
• Language: English