The Structure of Defects, the Electron Energy-Band Structure, and the Semiconductor–Metal Transition in PrBaCo2O5.5 Cobaltite: Ab Initio PAW Approach

Zhukov V., Chulkov E.

Physics of the Solid State, vol.63, no.3, pp.395-404, 2021 (SCI-Expanded, Scopus) identifier

  • Nəşrin Növü: Article / Article
  • Cild: 63 Say: 3
  • Nəşr tarixi: 2021
  • Doi nömrəsi: 10.1134/s1063783421030197
  • jurnalın adı: Physics of the Solid State
  • Jurnalın baxıldığı indekslər: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, Chemical Abstracts Core, INSPEC
  • Səhifə sayı: pp.395-404
  • Açar sözlər: cobaltites, electronic structure, PAW method, semiconductor-metal transition
  • Açıq Arxiv Kolleksiyası: Məqalə
  • Adres: Bəli

Qısa məlumat

Abstract: The electronic energy-band structure of the PrBaCo2O5 + δ cobaltite at the oxygen content close to 5.5 are calculated by the first-principle PAW methods. The semiconductor–metal phase transition at 5 + δ = 5.5 is shown to be a result of the transition of cobalt atoms in the octahedral environment from the high-spin to low-spin state. The cause of the appearance of the metallic conduction is an increase in the energy of antibonding eg states of pyramidal cobalt atoms, and, as a result, they are at the Fermi level, thereby determining the metallic character of the system. The effect of a deviation of the oxygen content from 5.5 on the energy-band structure and the conductivity is studied. The semiconductor–metal transition is shown can be observed only in a narrow range of the values of 5 + δ lower 5.5.