Locally symmetric oxygen vacancy around Cd impurities in CeO2

Autor(es)

Ferreira, W. L. ^[1] ; Pereira, L. F. D. ^[1] ; Neto, O. F. S. Leite ^[1] ; Maciel, L. S. ^[1] ; Goncalves, V. C. ^[1] ; Saxena, R. N. ^[1] ; Carbonari, A. W. ^[1] ; Costa, M. S. ^[2] ; Cabrera-Pasca, G. A. ^[3]

Afiliação do(s) autor(es)

^[1] Inst Pesquisas Energet & Nucl IPEN CNEN SP, Sao Paulo - Brazil

^[2] Univ Fed Para UFPA, Fac Ciencias Exatas & Tecnol, Fortaleza, Ceara - Brazil

^[3] Univ Fed Para UFPA, Programa Posgrad Ciencia & Engn Mat, Fortaleza, Ceara - Brazil

• Tipo de documento: Artigo Científico
• Fonte: Physical Review B; v. 104, n. 3 JUL 23 2021.
• Citações Web of Science: 0

Resumo

A detailed investigation of the electronic structure in the neighborhood of Cd impurities in CeO2 has been performed by ab initio calculations to elucidate the interplay between the oxygen vacancies and electric quadrupole interactions. The quadrupole frequency related to the major component of the electric-field gradient (EFG) at impurities sites from its neighboring charge density as well as its symmetry were calculated by simulating oxygen vacancies at oxygen nearest neighbor of Cd. Results show a very good agreement with experimental hyperfine interactions measurements at the Cd-111 nucleus replacing Ce at CeO2. A systematic mapping of oxygen vacancies in CeO2 supercells was proposed within the framework of density-functional theory using the WIEN2K code focusing on the electronic distribution in the vicinity of Cd impurities. Results show that the calculated values of EFG crucially depend on impurity-vacancy complex position and the striking axial symmetry observed when an oxygen monovancy is at the nearest neighborhood of Cd is explained by a rearrangement of its p orbitals. (AU)

• Processo FAPESP: 14/14001-1 - Projeto e construção de um espectrômetro digital: um equipamento mais eficiente e moderno para investigação de materiais utilizando técnica PAC
• Beneficiário: Rajendra Narain Saxena
• Modalidade de apoio: Auxílio à Pesquisa - Regular