チラルの分子からヒラルの同型液体
L E Hough1, M Spannuth, M Nakata
1Department of Physics and Liquid Crystal Materials Research Center, University of Colorado, Boulder, CO 80309, USA. hough@colorado.edu
Science (New York, N.Y.)
|July 25, 2009
まとめ
シンプルな曲った核の分子は,ユニークな液晶相を形成します. アキラルであるにもかかわらず,これらの相は,層の不安定性のために自発的なキラリティと高い光学回転力を発揮します.
科学分野:
- マテリアルサイエンス 材料科学
- 凝縮物質物理学 凝縮物質物理学
- 化学 化学は化学です.
背景:
- 曲った核の分子は,ユニークな性質を持つ液晶相を形成することができます.
- スメクティック液晶は,通常,平面流体層を示します.
- 自発的偏極化とキラリティは,アキラ分子では珍しい.
研究 の 目的:
- シンプルな曲ったコア分子によって形成された液晶相を調査するために.
- これらの相における自発的偏極化とキラリティの起源を理解する.
- これらの分子システムにおける安定性と対称性の破綻を特徴づける.
主な方法:
- 曲った核の分子の合成と特徴付け.
- 液晶相を研究するための顕微鏡とX線 difraktion.
- 回転力を測定するための光学測定.
主要な成果:
- 曲った核の分子は,平面流体層を持つスメクティック液晶相を形成する.
- 層内の構造的不一致は,サドルスプレーの変形に対する不安定につながります.
- 短距離の秩序と自発的なキラリティを持つマクロスコーピカルにイソトロピックな液体が形成されます.
- 高光回転力は,集積ドメインで観察されました.
結論:
- 曲った核の分子は,結晶の秩序なしに自発的なキラリティと極化を示すことができます.
- 層の不安定さがマクロスコピク特性を決定し,対称性が破られた同位体流体が生じる.
- これらの発見は,分子構造と液晶のマクロスコプ的性質の関係に関する新しい洞察を提供します.
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