Intrinsic ferromagnetism in CeO2: dispelling the myth of vacancy site localization mediated superexchange

Autor:	Graeme W. Watson, David O. Scanlon, Patrick R. L. Keating
Rok vydání:	2009
Předmět:	Ferromagnetism Condensed matter physics Chemistry Superexchange Vacancy defect chemistry.chemical_element General Materials Science Electron Magnetic semiconductor Condensed Matter Physics Oxygen Oxygen vacancy Electron localization function
Zdroj:	Journal of Physics: Condensed Matter. 21:405502
ISSN:	1361-648X 0953-8984
DOI:	10.1088/0953-8984/21/40/405502
Popis:	Intrinsic ferromagnetism in CeO(2) is a source of controversy in the literature and has been linked to the excess electrons left over upon oxygen vacancy formation on Ce sites neighbouring the vacancy. A recent theoretical study (Han et al 2009 Phys. Rev. B 79 100403) concluded that increased vacancy concentration changes the localization behaviour of CeO(2), resulting in some degree of charge localization in the vacancy site itself, which leads to superexchange and polarization effects that enhance the stability of ferromagnetism. In this report, we show conclusively that oxygen vacancy concentrations of up to 12.5% do not cause localization in the vacancy site, and that this is not responsible for any enhanced ferromagnetism. Investigation of oxygen vacancies on the (111), (110) and (100) low index surfaces also show no evidence for ferromagnetic preference.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_dedup___::d13c6f7c1f04134a31fce3adc86fc660 https://doi.org/10.1088/0953-8984/21/40/405502 Zobrazit plný text záznamu