Impurities in Perovskites: Evidence from ESR of Posistor Barium Titanate Ceramics

Autor:	A. M. Slipenyuk, E. P. Garmash, V. A. Mikheev, L. P. Yurchenko, V. D. Tkachenko, I. P. Bykov, Maya D. Glinchuk
Rok vydání:	2003
Předmět:	Strontium Materials science Doping Analytical chemistry Niobium chemistry.chemical_element Manganese Condensed Matter Physics Electronic Optical and Magnetic Materials Cerium chemistry.chemical_compound chemistry Impurity Barium titanate Strontium titanate
Zdroj:	Ferroelectrics. 288:235-241
ISSN:	1563-5112 0015-0193
Popis:	Room temperature measurements of ESR spectra were performed on BaTiO 3 ferroelectrics doped either by cerium or by niobium and strontium. Both types of samples were doped by manganese. In the samples of first type the most intensive line with g-factor 1,9612 was ascribed to paramagnetic centers Ti 3+ --Ce 3+ . We observed ESR spectra of Fe 3+ --V O centers and Mn 2+ also. In the samples with strontium a spectrum of six intensive lines, which corresponds to the hyperfine structure of Mn 2+, was observed. We study the dependency of Mn 2+ ESR spectrum intensity and electrical resistivity on strontium concentration. This effect was supposed to be related to the decrease of the grain sizes that result in migration of manganese and maybe niobium ions into intergrain air space. The mutual influence of Ce, Mn, Sr and Nb impurities, their charges and position in the lattice on the PTCR effect is discussed.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::643a250a6b1a739d9308ecac3d873e0a https://doi.org/10.1080/00150190390211639 Zobrazit plný text záznamu