Frustrated structure of an anticlinic-like smectic-C phase

• Tipo: Artigo em Revista Científica Internacional
• Data: 2006

Autores

Sebastiao, PJ (Autor) Outra; Carvalho, PS (Autor) FCUP; Chaves, MR (Autor) Outra; Nguyen, HT (Autor) Outra; Ribeiro, AC (Autor) Outra

Revista

Título: European Physical Journal E

Vol. 20

Páginas: 55-61

ISSN: 1292-8941

Editora: Springer Nature

Indexação

ISI Web of Knowledge - 5 Citações

Scopus - 5 Citações

Classificação Científica

FOS: Ciências da engenharia e tecnologias > Engenharia dos materiais

Outras Informações

ID Authenticus: P-004-KXN

DOI: 10.1140/epje/i2005-10119-2

Abstract (EN): We present a polarising optical microscopy study of the low-temperature anticlinic-like tilted mesophase of the liquid-crystal compound octylphenyl-2-chloro-4-(p-cyano-benzoyloxy) (DB8Cl). This mesophase has been described as a bilayer smectic structure in which the molecules within each layer are organised in an anticlinic way. The optical textures observed in samples with planar orientation show a double stripe pattern, with the lines aligned parallel to the rubbing direction, characteristic of a double periodic modulation of the refractive index of the material. The long-period modulation is temperature dependent and disappears for thin sample cells (< 5 mu m). The short-period modulation is nearly independent of the thickness of the cells. The experimental results are analysed in terms of a model which considers that there is a special distribution of the principal optical axis which may be in or out of the polariser-analyser plane. The observed periodic variation of the principal optical axis could not be interpreted in terms of the original structure proposed for this phase. DB8Cl presents a structure formed by dimers that can be viewed as flexible bent-core-like molecules, showing similarities with phases found in banana-like systems, but exhibiting a much more complex structure.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7