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
Diserahkan: 7
Disember 2009 / Diterima: 13 Julai 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
RUJUKAN
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*Pengarang
untuk surat-menyurat; email: onglh@usm.my
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