Order-disorder behavior in betaine arsenate studied by Raman scattering

• Tipo: Artigo em Revista Científica Internacional
• Data: 2000

Autores

Yuzyuk, YI (Autor) Outra; Moreira, JA (Autor) Outra; Almeida, A (Autor) FCUP; Chaves, MR (Autor) FCUP; Pinto, F (Autor) Outra; Klopperpieper, A (Autor) Outra

Revista

Título: Physical Review B - Condensed Matter and Materials Physics

Vol. 61

Páginas: 15035-15041

ISSN: 1098-0121

Editora: American Physical Society

Indexação

ISI Web of Knowledge - 8 Citações

Scopus - 9 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Física

Outras Informações

ID Authenticus: P-000-ZZV

DOI: 10.1103/physrevb.61.15035

Abstract (EN): A detailed study of Raman polarized spectra in betaine arsenate (BA) is presented. The results obtained give a significant contribution to the clarification of some controversial aspects of the critical behavior in BA. The temperature evolution of the hydrogen bonds stretching modes shows that different types of hydrogen bonds present different kinds of critical behavior. It also provides evidence of a proton ordering in the shorter hydrogen bond, i.e., along the c direction, at the para-ferroelectric phase transition. An order-disorder mechanism in the low-temperature region manifests itself by the progressive softening of the dynamical central peak observed in the tow-frequency spectra. Futhermore, a hint of a short-range ordering below 150 K was found which is related to the existence of polar clusters even in the paraelectric phase.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7