関連する実験動画
Updated: Jun 30, 2025
07:03
Measuring Magnetically-Tuned Ferroelectric Polarization in Liquid Crystals
Published on: August 15, 2018
8.8K
フェロ電気液晶のキラル基底状態
Priyanka Kumari1,2, Bijaya Basnet1,2, Maxim O Lavrentovich3,4
1Advanced Materials and Liquid Crystal Institute, Kent State University, Kent, OH 44242, USA.
Science (New York, N.Y.)
|March 21, 2024
まとめ
フェロ電気ネマティック液晶は,基底状態で自発的なキラリティを示し,左側と右側偏振の回転を形成する. 化学的構造ではなく分子秩序から生じ,イオンドーピングの影響を受けます.
科学分野:
- 柔らかい物質の物理
- 液晶科学について
- チラリティ研究
背景:
- 鉄電性ネマティック液晶 (FNLC) は,大きな二極瞬間を持つアキラル分子により,片方向に極性三次元的方向順序を有する.
- 化学的に誘発されたキラルセンターのないFNLCにおけるキラル性の自発的な出現は,未知の現象である.
研究 の 目的:
- 磁気流体結晶の平らな板の基本状態を調査する.
- 外部アライナメントの欠如で自発的なキラリティが生じるかどうかを判断する.
- 材料の構造を形作る際の 弾性と静電性エネルギーの相互作用を理解する
主な方法:
- プレート幾何学における鉄電気ネマティック液晶の理論モデル化.
- 基底状態へのエネルギー貢献 (弾性対静電) の分析.
- 観察されたキラル構造に対するイオンドーピングの効果の調査.
主要な成果:
- 無制限の鉄電気ネマティック・スラブの基底状態は本質的にキラルであり,自発的な左側と右側の偏振の回転を特徴とする.
- ヘリコイド変形とドメイン壁は弾性エネルギーを増加させますが,キラル回転は静電エネルギーを大幅に減少させます.
- イオンドーピングはキラル回転を弱め 静電相互作用への依存を示します
結論:
- アキラル分子における極性指向順序は 軟質系におけるヒラリティを 本質的に引き起こすことができる.
- 観察されたキラリティは,電気静的エネルギーを最小限に抑え,弾性エネルギーを上回る結果です.
- FNLCは,分子順序と静電力によって引き起こされるキラリティの出現を研究するための新しいプラットフォームを提供します.
関連する概念動画
02:25Chirality
24.2K
Chirality is a term that describes the lack of mirror symmetry in an object. In other words, chiral objects cannot be superposed on their mirror images. For example, our feet are chiral, as the mirror image of the left foot, the right foot, cannot be superposed on the left foot.
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
Chiral objects exhibit a sense of handedness when they interact with another chiral object. For example, our left foot can only fit in the left shoe and not in the right shoe. Achiral objects — objects that have...
24.2K
02:25Molecules with Multiple Chiral Centers
11.7K
Molecules that possess multiple chiral centers can afford a large number of stereoisomers. For instance, while some molecules like 2-butanol have one chiral center, defined as a tetrahedral carbon atom with four different substituents attached, several molecules like butane-2,3-diol have multiple chiral centers. A simple formula to predict the number of stereoisomers possible for a molecule with n chiral centers is 2n. However, there can be a lower number where some of the stereoisomers are...
11.7K
02:30Chirality at Nitrogen, Phosphorus, and Sulfur
5.7K
Chirality is most prevalent in carbon-based tetrahedral compounds, but this important facet of molecular symmetry extends to sp3-hybridized nitrogen, phosphorus and sulfur centers, including trivalent molecules with lone pairs. Here, the lone pair behaves as a functional group in addition to the other three substituents to form an analogous tetrahedral center that can be chiral.
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
A consequence of chirality is the need for enantiomeric resolution. While this is theoretically possible for all...
5.7K
02:30Chirality in Nature
13.4K
Chirality is the most intriguing yet essential facet of nature, governing life’s biochemical processes and precision. It can be observed from a snail shell pattern in a macroscopic world to an amino acid, the minutest building block of life. Most of the snails around the world have right-coiled shells because of the intrinsic chirality in their genes. All the amino acids present in the human body exist in an enantiomerically pure state, except for glycine - the sole achiral amino acid.
13.4K
02:24Properties of Enantiomers and Optical Activity
17.0K
It is essential to understand the difference between chiral and achiral interactions and the implications thereof in optical activity and their applications. Just as our feet, which are chiral, interact uniquely with chiral objects, such as a pair of shoes, but identically with achiral socks, enantiomers of a molecule exhibit different properties only when they interact with other chiral media. An example of a significant implication from this facet is the phenomenon known as optical activity,...
17.0K
02:52Stereoisomerism
11.9K
Isomerism in Complexes
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
Isomers are different chemical species that have the same chemical formula.
Transition metal complexes often exist as geometric isomers, in which the same atoms are connected through the same types of bonds but with differences in their orientation in space. Coordination complexes with two different ligands in the cis and trans positions from a ligand of interest form isomers. For example, the octahedral [Co(NH3)4Cl2]+ ion has two isomers (Figure 1) In the cis...
11.9K