Lattice dynamics and phase transitions in betaine arsenate

Authors
Moreira, JA Santos, ML Chaves, MR Almeida, A Klopperpieper, A Gervais, F
Citation
Ja. Moreira et al., Lattice dynamics and phase transitions in betaine arsenate, FERROELECTR, 239(1-4), 2000, pp. 963-970
Citations number
10
Categorie Soggetti
Apllied Physucs/Condensed Matter/Materiales Science
Journal title
FERROELECTRICS
ISSN journal
00150193 → ACNP
Volume
239
Issue
1-4
Year of publication
2000
Pages
963 - 970
Database
ISI
SICI code
0015-0193(2000)239:1-4<963:LDAPTI>2.0.ZU;2-B
Abstract
In this work we present an experimental study of infrared reflectivity spec troscopy in betaine arsenate (BA). The results obtained corroborate the ord er-disorder character of the phase transition in BA at 120 K, observed by R aman spectroscopy, They also provide a clear evidence of the proton orderin g in the hydrogen bonds, associating different ordering temperatures to dif ferent bonds orientations. Precursory effects are observed well above 120 K .