NOの動きを,結晶 [Fe ((Porph)) ((NO)) ((1-MeIm)) ]でマッピングしています
Nathan J Silvernail1, Alexander Barabanschikov, J Timothy Sage
1Department of Chemistry and Biochemistry, University of Notre Dame, Notre Dame, Indiana 46556, USA.
Journal of the American Chemical Society
|January 24, 2009
まとめ
鉄ポルフィリナートのニトロシルリガンドは,温度に依存する方向性障害を示す. 分子間相互作用は,NOリガンドの動きを制御し,制限された方向性を許し,固体状態への移行に影響を与えます.
科学分野:
- 無機化学 無機化学とは
- 固体化学 固体化学
- クリスタログラフィーです.
背景:
- ニトロシル (NO) リガンドの指向性障害は,鉄のポルフィリネートに多く見られる.
- この障害を理解することは,鉄のポルフィリナート複合体の特徴化にとって極めて重要です.
研究 の 目的:
- 鉄のポルフィリネートにおけるニトロシルリガンドの秩序/混乱現象を分析する.
- NOリガンドの指向に対する非結合接触と分子間相互作用の影響を調査する.
主な方法:
- マルチ温度結晶学的データの分析.
- 半経験的関数を用いて非結合接触と潜在エネルギーの計算.
- 密度関数理論 (DFT) の計算により,回転障壁を決定する.
主要な成果:
- 非結合コンタクトは,構造変化と相関する温度依存の変動を示します.
- 分子間相互作用は,NOリガンドの動きを,限られた一連の方向に制限する.
- ヴァント・ホフ分析により,固体状態への移行における自由エネルギーとエンタルピーの評価が可能になった.
結論:
- 固体相互作用は,鉄のポルフィリナートにおけるニトロシルリガンドの方向性を決定する.
- この研究は,NOリガンド障害のダイナミクスとエネルギー景観の洞察を提供します.
- DFTの計算は,NOの方向が赤道的なボンド距離に与える影響を明らかにしています.
関連する概念動画
Imperfections in Crystal Structure: Point, Line and Plane Defects
A perfect crystal, in theory, has a uniform structure with the same unit cell and lattice points throughout. However, any deviation from this periodic arrangement is known as an imperfection or defect. These defects can be categorized into three types: point, line, and plane defects.Point defects occur when there is a deviation from the ideal due to missing atoms, displaced atoms, or additional atoms. These imperfections might occur due to imperfect packing during crystallization or because of...
Imperfections in Crystal Structure: Stoichiometric Point Defects
Schottky defects arise when some lattice points in a crystal, such as those in NaCl, remain unoccupied, creating lattice vacancies without disturbing the overall electrical neutrality of the crystal. This defect is common in ionic crystals where the positive and negative ions are similar in size, as seen in sodium chloride and cesium chloride. The presence of Schottky defects enables the crystal to conduct electricity to a small extent through an ionic mechanism. Electric fields cause nearby...
Imperfections in Crystal Structure: Non-Stoichiometric Defects
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...
Crystallographic Point Groups
Crystallographic point groups represent the various symmetry operations that can occur within crystals. They are unique in that at least one point will always remain unchanged during these actions. For instance, consider the triclinic system. This system, devoid of any axis or plane of symmetry, aligns with the C1 and Ci point groups.where Cᵢ is characterized solely by a center of inversion.Contrastingly, the monoclinic system introduces an element of symmetry. This system with one plane and...
Symmetry Elements in a Crystal
Crystal symmetry operations are isometric transformations that map objects onto indistinguishable copies while preserving distances, angles, and volumes. The simplest symmetry operation is translation, which shifts the entire infinite crystal lattice parallelly by a translation vector.Crystallographic rotations involve rotations by an angle of 2π/n around an axis without changing the positions of points on the axis. It is called the rotational axis of the symmetry, denoted by n. The combination...
Lattice Centering and Coordination Number
The structure of a crystalline solid, whether a metal or not, is best described by considering its simplest repeating unit, which is referred to as its unit cell. The unit cell consists of lattice points that represent the locations of atoms or ions. The entire structure then consists of this unit cell repeating in three dimensions. The three different types of unit cells present in the cubic lattice are illustrated in Figure 1.
Types of Unit Cells
Imagine taking a large number of identical...
Types of Unit Cells
Imagine taking a large number of identical...

