http://www.cnr.it/ontology/cnr/individuo/prodotto/ID22137

Defect chemistry and dielectric properties of Yb3+:CaTiO3 perovskite (Articolo in rivista)

Type

Prodotto della ricerca (Classe)
Articolo in rivista (Classe)

Label

Defect chemistry and dielectric properties of Yb3+:CaTiO3 perovskite (Articolo in rivista) (literal)

Anno

2008-01-01T00:00:00+01:00 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#doi

10.1063/1.2828149 (literal)

Alternative label

M. Bassoli; M. T. Buscaglia; C. Bottino; V. Buscaglia; M. Molinari; F. Maglia; G. Parravicini; M. Dapiaggi (2008)
Defect chemistry and dielectric properties of Yb3+:CaTiO3 perovskite
in Journal of applied physics (online); American Institute of Physics, Melville [NY] (Stati Uniti d'America)
(literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#autori

M. Bassoli; M. T. Buscaglia; C. Bottino; V. Buscaglia; M. Molinari; F. Maglia; G. Parravicini; M. Dapiaggi (literal)

Pagina inizio

014104-1 (literal)

Pagina fine

014104-10 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#url

http://puma.isti.cnr.it/linkres.php?resource=cnr.ieni/cnr.ieni.ge/2008-A0-001 (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#numeroVolume

103 (literal)

Rivista

Journal of applied physics (Rivista)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#pagineTotali

10 (literal)

Note

Scopu (literal)
ISI Web of Science (WOS) (literal)

Http://www.cnr.it/ontology/cnr/pubblicazioni.owl#affiliazioni

Institute of Energetics and Interphases, National Research Council, Via De Marini 6, I-16149 Genoa, Italy; IENI/CNR, INSTM, and Department of Physical Chemistry, University of Pavia, Viale Taramelli, 16, I-27100 Pavia, Italy; Department of Physics, University of Pavia, Via Bassi, 6, I-27100 Pavia, Italy; Department of Earth Sciences, University of Milano, Via Botticelli 23, I-20133 Milano, Italy (literal)

Titolo

Defect chemistry and dielectric properties of Yb3+:CaTiO3 perovskite (literal)

Abstract

The defect chemistry of Yb3+ :CaTiO3 solid solutions has been investigated both theoretically and experimentally. Three different incorporation mechanisms with similar solution energy were predicted for Yb3+ by atomistic simulation: (i) Ca site substitution with Ca vacancy compensation; (ii) Ti site substitution with O vacancy compensation; (iii) simultaneous substitution at both Ca and Ti sites with self-compensation. X-ray diffraction and scanning electron microscopy results strongly support the possibility to realize the above defect chemistries in CaTiO3 by changing the Ca/Ti ratio to force Yb3+ on the Ca site (Ca/Ti<1), on Ti site (Ca/Ti>1), or on both sites (Ca/Ti=1) according to the calculations. The temperature dependence of the relative dielectric constant (10(2)-10(5) Hz) of ceramics corresponding to predominant Yb substitution either at the Ca site or the Ti site is qualitatively similar to that of undoped CaTiO3. The Curie-Weiss temperature is shifted to more negative values in comparison to CaTiO3, suggesting that the compositions Ca1-3/2xYbxTiO3 and CaYbxTi1-xO3 are further driven away from the ferroelectric instability. In contrast, the dielectric properties (10(2)-10(5) Hz) of ceramics corresponding to Ca1-x/2YbxTi1-x/2O3 are radically different. The relative dielectric constant is increased of about one order of magnitude (2200 at 30 K), is almost independent of temperature, with a maximum variation of 20% in range of 20-300 K, and shows frequency dispersion above 150 K. The loss tangent at 20-300 K is <5% for frequencies >=1 kHz. The possible mechanism for the observed dielectric behavior is discussed. (literal)

Editore