Sains Malaysiana 40(1)(2011): 9–11

Transitions of Smectic A to Tilted Phases in Thin Free

Standing Films of Liquid Crystal

(Peralihan Fasa Smektik A ke Fasa Condong dalam Filem Nipis Hablur Cecair Berdiri Bebas)

Chia-Yuee Lum & Lye-Hock Ong*

School of Physics, Universiti Sains Malaysia, 11800 USM, Penang, Malaysia

Mojca Čepic

Faculty of Education, University of Ljubljana

Kardeljeva pl. 16, 1000 Ljubljana, Slovenia

Received: 7 December 2009 / Accepted: 13 July 2010

ABSTRACT

The transition of orthogonal smectic A (SmA) phase to the tilted phases, upon lowering the temperature, is explored with a discrete phenomenological model and the phase diagrams are presented. The results show that the transition of SmA to uniplanar structures can be affected by the effect of chirality. The areas showing the uniplanar phase in the phase diagrams diminish with the increase in effect of chirality.

Keywords: Liquid crystal phase transition; model and theory; thin films

ABSTRAK

Peralihan fasa smektik A (SmA) ke fasa condong hablur cecair, dengan menurunkan suhu, telah dikaji dengan menggunakan model fenomenologi berbentuk diskrit dan gambarajah fasa peralihan ini dipaparkan. Keputusan menunjukkan peralihan fasa SmA ke fasa uniplanar dipengaruhi oleh kesan kekiralan. Luas kawasan untuk fasa uniplanar dalam gambarajah fasa semakin menyusut dengan penambahan kesan kekiralan.

Kata kunci: Filem nipis; model dan teori; peralihan fasa hablur cecair

REFERENCES

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*Corresponding author; email: onglh@usm.my