関連する実験動画
Updated: Jul 18, 2026

12:29
Optimization of Crystal Growth for Neutron Macromolecular Crystallography
Published on: March 13, 2021
形態学の設計と制御に向けた協調ポリマーの化学反応による結晶の成長にインスパイアされた
Shigeyuki Masaoka1, Daisuke Tanaka, Hiroyuki Kitahata
1Department of Synthetic Chemistry and Biological Chemistry, Graduate School of Engineering, Kyoto University, Katsura, Nishikyo-ku, Kyoto 615-8510, Japan.
Journal of the American Chemical Society
|December 7, 2006
まとめ
この研究は,協調ポリマーのための新しい結晶成長システムを導入し,表面化学反応がダンベルやスーパーラットのようなマクロスコープの結晶形にどのように影響するかを明らかにします.
科学分野:
- マテリアルサイエンス 材料科学
- クリスタルグラフィーです.
- 化学合成とは,化学合成というものです.
背景:
- コーディネーションポリマーは,高度なアプリケーションのために調節可能な特性を提供します.
- 結晶の成長メカニズムを理解することは,物質形態学の制御に不可欠です.
- ヘキザザトリフェニレン誘導体などの複雑な有機リガンドの合成は,ユニークな課題を提示しています.
研究 の 目的:
- 特定の調整枠組みのための新しい結晶成長システムを報告する.
- ダンベル,ドッグホイール,スーパーラットなどの様々な結晶形態の形成を調査する.
- 顕微鏡の結晶構造を決定する表面化学反応の役割を明らかにする.
主な方法:
- {[Cu3(CN) 3{hat-(CN) 3(OEt) 3}]]nの結晶化は,hat-(CN) 6,エタノール,および銅の反応によって行われます.
- 採取した結晶の形態学的分析 (ダンベル,歯車,スーパーラティス).
- 結晶の成長率の動的分析は,c軸に平行および垂直である.
- 反応-拡散プロセスとしてシステムをモデリングする.
主要な成果:
- コーディネーション・フレームワーク {[Cu3(CN) 3{hat-(CN) 3(OEt) 3}]}n.n.の成功シンセシス
- 観測された結晶形態には,ダンベル,ドッグホイール,および周期的な分岐を持つスーパーラティスが含まれる.
- ダンベル結晶には,結晶学軸に沿った異なる成長率が認められた.
- 実験結果は,反応拡散モデルによって成功裏に再現されました.
結論:
- 表面の化学反応は,マクロスコープの結晶の形状に大きく影響する.
- 開発されたシステムは,結晶の成長と構造を制御するための洞察を提供します.
- 反応-拡散プロセスは,観測された結晶形成パターンを理解するための鍵です.
関連する概念動画
Crystal Growth: Principles of Crystallization
Crystallization is a phase transformation process in which crystals are precipitated from a supersaturated solution or formed from other sources. During crystallization, atoms or molecules arrange themselves into a well-defined, rigid crystal lattice to minimize energy.
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent – the...
Cationic Chain-Growth Polymerization: Mechanism
The cationic polymerization mechanism consists of three steps: initiation, propagation, and termination. In the initiation step of the polymerization process, the π bond of a monomer gets protonated by the Lewis acid catalyst, which is formed from boron trifluoride and water. The protonation of the π bond generates a carbocation stabilized by the electron‐donating group. In the propagation step, the π bond of the second monomer acts as a nucleophile and attacks the generated carbocation,...
Ziegler–Natta Chain-Growth Polymerization: Overview
Ziegler–Natta polymerization is another form of addition or chain‐growth polymerization used for synthesizing linear polymers over branched polymers. The catalyst used for polymerization is the Ziegler–Natta catalyst, named after Karl Ziegler and Giulio Natta, who developed it in 1953. This catalyst is an organometallic complex of titanium tetrachloride and triethyl aluminum, with the active form of the catalyst being an alkyl titanium compound. Using the Ziegler–Natta catalyst, high molecular...
Step-Growth Polymerization: Overview
Step-growth or condensation polymerization is a stepwise reaction of bi or multifunctional monomers to form long-chain polymers. As all the monomers are reactive, most of the monomers are consumed at the early stages of the reaction to form small chains of reactive oligomers, which then combine to form long polymer chains in the late stages. Hence, the reaction has to proceed for a long time to achieve high molecular weight polymers.
Many natural and synthetic polymers are produced by...
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Anionic Chain-Growth Polymerization: Mechanism
The mechanism for anionic chain-growth polymerization involves initiation, propagation, and termination steps. In the initiation step, a nucleophilic anion, such as butyl lithium, initiates the polymerization process by attacking the π bond of the vinylic monomer. As a result, a carbanion, stabilized by the electron‐withdrawing group, is generated. The resulting carbanion acts as a Michael donor in the propagation step and attacks the second vinylic monomer, which acts as a Michael acceptor.
Anionic Chain-Growth Polymerization: Overview
The polymerization process that involves carbanion as an intermediate is called anionic polymerization. It is also a type of addition or chain-growth polymerization. Anionic polymerization gets initiated by a strong nucleophile such as an organolithium or a Grignard reagent. The most commonly used initiator for anionic polymerization is butyl lithium. Monomers involved in anionic polymerization must possess a vinyl group bonded to one or two electron-withdrawing groups. For instance,...

