title: Microscopic distribution of metal dopants and anion vacancies in Fe-doped BaTiO(3-δ) single crystals.
abstract: A detailed microscopic structural study on two single crystalline dilute magnetic oxides, BaTi0.95Fe0.05O(3-δ) with and without perceptible δ, has been carried out. Although it has been reported earlier that varying δ significantly affects high temperature ferromagnetism, the real distribution/redistribution of vacancies and dopant Fe ions inside the 6H hexagonal structure was never probed. This study reveals that oxygen vacancies reduce the dopant Fe(3+) ions to Fe(2+) and mostly accumulate around these Fe(2+) ions. Another distinct trend is the tendency of the dopant Fe ions to get closer instead of being distributed randomly, thereby creating Fe2(2+)O(9-δ') like dimers within the 6H hexagonal unit cell. This experimental observation definitively confirms previous hypotheses based on theoretical models.
authors.affiliation: Centre for Advanced Materials, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India.
authors.forename: Tanushree
authors.initials: T
authors.lastname: Chakraborty
authors.forename: Carlo
authors.initials: C
authors.lastname: Meneghini
authors.forename: Giuliana
authors.initials: G
authors.lastname: Aquilanti
authors.forename: Sugata
authors.initials: S
authors.lastname: Ray