関連する実験動画
Updated: Jun 26, 2026

06:53
Photoelectron Imaging of Anions Illustrated by 310 Nm Detachment of F−
Published on: July 27, 2018
Ag上でのNO二元体内の光誘導抽象反応 ((111))
Ki Hyun Kim1, Kazuo Watanabe, Dietrich Menzel
1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
Journal of the American Chemical Society
|January 17, 2009
まとめ
窒素 (N2) と酸化窒素 (N2O) は,銀の表面上の二酸化窒素 ((NO) 2) のレーザー誘発反応から形成されます. その結果生成されるN2は,表面の反発により高エネルギーで吸収されます.
科学分野:
- 表面科学とは,地表科学である.
- フォトケミストリー フォトケミストリー
- レーザーで誘発された反応
背景:
- 二酸化窒素 ((NO) 2) は,大気化学と表面反応に関連する分子です.
- 金属表面の光反応を理解することは,触媒と材料科学にとって極めて重要です.
研究 の 目的:
- 銀の表面 (Ag(111) に吸収された (NO) 2のナノ秒レーザー誘発光反応を調査する.
- フォトプロダクトを特定し,銀の表面の役割を含む反応機構を理解する.
主な方法:
- 大量選択光誘導脱吸収 (PID) は,脱吸収分子を検出するために使用されました.
- 飛行時間 (TOF) の測定は,光製品の変換エネルギーを決定するために使用されました.
主要な成果:
- 窒素 (N2) と酸化窒素 (N2O) は,単一の (NO) 2分子内の抽象反応によって形成された光産物として識別されました.
- N2光プロダクトは,5700 Kの高い変換温度で脱吸収し,強力な表面反発を示した.
- Ag111) 表面は, (NO) 2. 2 の N-N 結合を短縮することによって,N2O と N2 の形成を促進することが判明しました.
結論:
- ナノ秒レーザー照射は,分子内抽象反応を通じて, (NO) 2 から Ag 上の (NO) 2 から N2 と N2O の形成を誘導します.
- 銀の表面は, (NO) 2分子を活性化させ,N2製品の脱吸収ダイナミクスに影響を与える上で重要な役割を果たします.
関連する概念動画
Radical Formation: Abstraction
The electron of an atom can be abstracted from a compound by a relatively unstable radical to generate a new radical of relatively greater stability. For example, an initiator which forms radicals by homolysis can abstract a suitable species like a hydrogen atom or a halogen atom from a compound to generate a new radical. This ability of radicals to propagate by abstraction is a crucial feature of radical chain reactions.
Even though homolysis produces radicals, it is different from radical...
Even though homolysis produces radicals, it is different from radical...
Cycloaddition Reactions: MO Requirements for Photochemical Activation
Some cycloaddition reactions are activated by heat, while others are initiated by light. For example, a [2 + 2] cycloaddition between two ethylene molecules occurs only in the presence of light. It is photochemically allowed but thermally forbidden.
Photochemical Electrocyclic Reactions: Stereochemistry
The absorption of UV–visible light by conjugated systems causes the promotion of an electron from the ground state to the excited state. Consequently, photochemical electrocyclic reactions proceed via the excited-state HOMO rather than the ground-state HOMO. Since the ground- and excited-state HOMOs have different symmetries, the stereochemical outcome of electrocyclic reactions depends on the mode of activation; i.e., thermal or photochemical.
Selection Rules: Photochemical Activation
Selection Rules: Photochemical Activation
Radical Formation: Homolysis
A bond is formed between two atoms by sharing two electrons. When this bond is broken by supplying sufficient energy, either two electrons can be taken up by one atom forming ions by the cleavage called heterolysis, or the two electrons are shared by two atoms, with one each creating radicals by the cleavage called homolysis.
Deactivation Processes: Jablonski Diagram
Luminescence, the emission of light by a substance that has absorbed energy, is a process that involves the interaction of molecules with light. The energy-level diagram, or Jablonski diagram, is a graphical representation of these interactions, illustrating the various states and transitions a molecule can undergo. In a typical Jablonski diagram, the lowest horizontal line represents the ground-state energy of the molecule, which is usually a singlet state. This state represents the energies...
The Photochemical Reaction Center
Reaction centers are pigment-protein complexes that initiate energy conversion from photons to chemical entities. Therefore, photochemical reaction center is a more appropriate term that describes these complexes. The Nobel laureates Robert Emerson and William Arnold provided the first experimental evidence of photochemical reaction centers by demonstrating the participation of nearly 2,500 chlorophyll molecules for the release of just one molecule of oxygen. Despite thousands of photosynthetic...
![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
