Study of Inelastic Light Scattering in LaxSr(1-1.5x)TiO3

• Tipo: Artigo em Livro de Atas de Conferência Internacional
• Data: 2008

Autores

Almeida, A (Autor) FCUP; Correia, TM (Autor) Outra; Chaves, MR (Autor) Outra; Vilarinho, PM (Autor) Outra; Kholkin, A (Autor) Outra

Ata de Conferência Internacional

Título: Advanced Materials Forum IV

Páginas: 148-152

IV International Materials Symposium Materiais 2007 and XIII Encontro da Sociedade Portuguesa de Materiais

Porto, Portugal, April 1-4, 2007

Indexação

ISI Web of Knowledge - 0 Citações

Scopus - 0 Citações

Outras Informações

ID Authenticus: P-004-277

Abstract (EN): In an attempt to gain a better understanding of the lattice dynamics in lanthanum doped SrTiO3 (STO) ceramics, with general formulae LaxSr(1-1.5x)TiO3, We have carried out a detailed Raman study of the x=0.0133 ceramic in the temperatures ranging from 10K to room temperature. Our results show that lanthanum substitution gives rise to new features in the Raman spectra. The Rayleigh band and the extra Raman-forbidden infrared active modes observed provide evidence for the existence of disorder in the system, apparently associated with grain structure, and lattice defects. Moreover, the absence of a TO1 polar soft mode supports the non-existence of a ferroelectric phase at low temperatures. The shift of the para-antiferrodistorsive transition temperature towards higher temperatures clearly evidences that the replacement of Strontium by Lanthanum occurs at the lattice A-site.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 5