trunk/tengDissertation/LiquidCrystal.tex

\chapter{\label{chapt:liquidcrystal}LIQUID CRYSTAL}

\section{\label{liquidCrystalSection:introduction}Introduction}
% liquid crystal

Long range orientational order is one of the most fundamental
properties of liquid crystal mesophases. This orientational
anisotropy of the macroscopic phases originates in the shape
anisotropy of the constituent molecules. Among these anisotropy
mesogens, rod-like (calamitic) and disk-like molecules have been
exploited in great detail in the last two decades. Typically, these
mesogens consist of a rigid aromatic core and one or more attached
aliphatic chains. For short chain molecules, only nematic phases, in
which positional order is limited or absent, can be observed,
because the entropy of mixing different parts of the mesogens is
paramount to the dispersion interaction. In contrast, formation of
the one dimension lamellar sematic phase in rod-like molecules with
sufficiently long aliphatic chains has been reported, as well as the
segregation phenomena in disk-like molecules.

% banana shaped
Recently, the banana-shaped or bent-core liquid crystal have became
one of the most active research areas in mesogenic materials and
supramolecular chemistry. Unlike rods and disks, the polarity and
biaxiality of the banana-shaped molecules allow the molecules
organize into a variety of novel liquid crystalline phases which
show interesting material properties. Of particular interest is the
spontaneous formation of macroscopic chiral layers from achiral
banana-shaped molecules, where polar molecule orientational ordering
is shown within the layer plane as well as the tilted arrangement of
the molecules relative to the polar axis. As a consequence of
supramolecular chirality, the spontaneous polarization arises in
ferroelectric (FE) and antiferroelectic (AF) switching of smectic
liquid crystal phases, demonstrating some promising applications in
second-order nonlinear optical devices.

The most widely investigated mesophase formed by banana-shaped
moleculed is the $\text{B}_2$ phase, which is also known as
$\text{SmCP}$.

%Previous Theoretical Studies

\section{\label{liquidCrystalSection:model}Model}

\section{\label{liquidCrystalSection:methods}Methods}

\section{\label{liquidCrystalSection:resultDiscussion}Results and Discussion}
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#	Content
1	\chapter{\label{chapt:liquidcrystal}LIQUID CRYSTAL}
2
3	\section{\label{liquidCrystalSection:introduction}Introduction}
4	% liquid crystal
5
6	Long range orientational order is one of the most fundamental
7	properties of liquid crystal mesophases. This orientational
8	anisotropy of the macroscopic phases originates in the shape
9	anisotropy of the constituent molecules. Among these anisotropy
10	mesogens, rod-like (calamitic) and disk-like molecules have been
11	exploited in great detail in the last two decades. Typically, these
12	mesogens consist of a rigid aromatic core and one or more attached
13	aliphatic chains. For short chain molecules, only nematic phases, in
14	which positional order is limited or absent, can be observed,
15	because the entropy of mixing different parts of the mesogens is
16	paramount to the dispersion interaction. In contrast, formation of
17	the one dimension lamellar sematic phase in rod-like molecules with
18	sufficiently long aliphatic chains has been reported, as well as the
19	segregation phenomena in disk-like molecules.
20
21	% banana shaped
22	Recently, the banana-shaped or bent-core liquid crystal have became
23	one of the most active research areas in mesogenic materials and
24	supramolecular chemistry. Unlike rods and disks, the polarity and
25	biaxiality of the banana-shaped molecules allow the molecules
26	organize into a variety of novel liquid crystalline phases which
27	show interesting material properties. Of particular interest is the
28	spontaneous formation of macroscopic chiral layers from achiral
29	banana-shaped molecules, where polar molecule orientational ordering
30	is shown within the layer plane as well as the tilted arrangement of
31	the molecules relative to the polar axis. As a consequence of
32	supramolecular chirality, the spontaneous polarization arises in
33	ferroelectric (FE) and antiferroelectic (AF) switching of smectic
34	liquid crystal phases, demonstrating some promising applications in
35	second-order nonlinear optical devices.
36
37	The most widely investigated mesophase formed by banana-shaped
38	moleculed is the $\text{B}_2$ phase, which is also known as
39	$\text{SmCP}$.
40
41	%Previous Theoretical Studies
42
43	\section{\label{liquidCrystalSection:model}Model}
44
45	\section{\label{liquidCrystalSection:methods}Methods}
46
47	\section{\label{liquidCrystalSection:resultDiscussion}Results and Discussion}