構造 単結晶X線 difraktionによって明らかにされた2D共性有機フレームワークの進化
Lezhi Yi1, Yijun Gao1, Shuming Luo1
1Key Laboratory of Biomedical Polymers Ministry of Education, College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, China.
Journal of the American Chemical Society
|July 11, 2024
まとめ
この研究では,化学反応と溶媒変化の過程で起こる動的変異と構造的進化を詳細に説明する2次元共性有機フレームワーク (COF) の9つの結晶構造が明らかになりました. 長期注文は,これらの構造的な変化を通して維持されます.
科学分野:
- 材料科学
- クリスタルグラフィー
- 超分子化学
背景:
- 協和有機フレームワーク (COF) は,調節可能な構造を持つ結晶性多孔ポリマーである.
- 2D COFの構造的ダイナミクスを理解することは,機能的な材料の設計に不可欠です.
- 以前の研究では,ダイナミックなプロセス中のCOFに関する詳細な構造情報が欠けていました.
研究 の 目的:
- 2D COF とその誘導体の詳細な結晶構造を解明する.
- 化学反応と溶媒交換中の2DCOFの構造的進化を調査する.
- 分子構造とフレームワークの順序の関係についての洞察を提供するためです.
主な方法:
- 単結晶X線微分法 (SCXRD) を用いて,9つの結晶構造を決定した.
- 高解像度SCXRDデータ (最大0.85 Å) は,構造パラメータの詳細な分析を可能にしました.
- 溶媒の交換/損失および化学的誘導過程で捕捉された動的状態をin situまたはex situで分析する.
主要な成果:
- スタッキングモード,層間距離,孔口,分子傾斜角度を含む詳細な構造パラメータは,親COF,5の誘導体,3の動的状態で決定されました.
- この研究では,構造的進化を推進する分子構成要素の段階的な変形が観察されました.
- 重要な構造変化にもかかわらず,2D COFの長距離オーダーリングは維持されました.
結論:
- この研究は,2D COFのダイナミックな行動に関する前例のない構造的洞察を提供します.
- 構造の進化を理解することは,アプリケーションのCOF特性を制御する鍵です.
- トランスフォーメーション中の長期的秩序の維持は,COFの枠組みの強さを強調しています.
関連する概念動画
02:18X-ray Crystallography
23.9K
The size of the unit cell and the arrangement of atoms in a crystal may be determined from measurements of the diffraction of X-rays by the crystal, termed X-ray crystallography.
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
Diffraction
Diffraction is the change in the direction of travel experienced by an electromagnetic wave when it encounters a physical barrier whose dimensions are comparable to those of the wavelength of the light. X-rays are electromagnetic radiation with wavelengths about as long as the distance between neighboring...
23.9K
02:58Crystal Field Theory - Octahedral Complexes
26.3K
Crystal Field Theory
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...
26.3K
02:18Network Covalent Solids
13.4K
Network covalent solids contain a three-dimensional network of covalently bonded atoms as found in the crystal structures of nonmetals like diamond, graphite, silicon, and some covalent compounds, such as silicon dioxide (sand) and silicon carbide (carborundum, the abrasive on sandpaper). Many minerals have networks of covalent bonds.
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
To break or to melt a covalent network solid, covalent bonds must be broken. Because covalent bonds are relatively strong, covalent network solids are typically...
13.4K
02:46Crystal Field Theory - Tetrahedral and Square Planar Complexes
42.0K
Tetrahedral Complexes
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
Crystal field theory (CFT) is applicable to molecules in geometries other than octahedral. In octahedral complexes, the lobes of the dx2−y2 and dz2 orbitals point directly at the ligands. For tetrahedral complexes, the d orbitals remain in place, but with only four ligands located between the axes. None of the orbitals points directly at the tetrahedral ligands. However, the dx2−y2 and dz2 orbitals (along the Cartesian axes) overlap with the ligands less than the dxy,...
42.0K
02:22Structures of Solids
14.1K
Solids in which the atoms, ions, or molecules are arranged in a definite repeating pattern are known as crystalline solids. Metals and ionic compounds typically form ordered, crystalline solids. A crystalline solid has a precise melting temperature because each atom or molecule of the same type is held in place with the same forces or energy. Amorphous solids or non-crystalline solids (or, sometimes, glasses) which lack an ordered internal structure and are randomly arranged. Substances that...
14.1K
02:37Metallic Solids
18.4K
Metallic solids such as crystals of copper, aluminum, and iron are formed by metal atoms. The structure of metallic crystals is often described as a uniform distribution of atomic nuclei within a “sea” of delocalized electrons. The atoms within such a metallic solid are held together by a unique force known as metallic bonding that gives rise to many useful and varied bulk properties.
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability....
18.4K