量子状态解决了速度控制OH与NO基的双分子碰撞
Moritz Kirste1, Xingan Wang, H Christian Schewe
1Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany.
概括
本研究测量了两个开分子, (OH) 和氧化 (NO) 基的状态解析不弹性散射. 结果揭示了静电力在复杂分子碰撞中的关键作用.
科学领域:
- 化学物理 化学物理
- 分子碰撞分子碰撞
- 量子动力学 量子动力学是什么?
背景情况:
- 原子-分子碰撞在量子层面上是众所周知的.
- 检测两个状态选择分子之间的相互作用仍然是一个重大挑战.
研究的目的:
- 测量两个开分子之间的碰撞的状态解析不弹性散射截面.
- 研究静电力在分子相互作用中的作用.
主要方法:
- 在交叉光束设置中利用了Stark减速的基 (OH) 激素和六极聚焦的氧化 (NO) 激素.
- 测量绝对旋转和旋转轨道不弹性散射截面.
- 采用基于ab initio的潜在能量表面的量子合通道计算.
主要成果:
- 获得OH-NO碰撞的状态解析不弹性散射截面.
- 通过从70到300厘米的碰撞能量测量了横截面.
- 在实验数据和理论计算之间发现了合理的一致性.
结论:
- 静电力在复杂的分子碰撞过程中起着至关重要的作用.
- 该研究为分子相互作用的理论模型提供了一个基准.
- 进步了对开分子碰撞中的量子动力学的理解.
相关概念视频
Radical Reactivity: Overview
Radicals, the highly reactive species, gain stability by undergoing three different reactions. The first reaction involves a radical-radical coupling, in which a radical combines with another radical, forming a spin‐paired molecule. The second reaction is between a radical and a spin‐paired molecule, generating a new radical and a new spin‐paired molecule. The third reaction is radical decomposition in a unimolecular reaction, forming a new radical and a spin‐paired molecule. These three...
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...
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.
Radical Formation: Overview
A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the latter, also known...
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the latter, also known...
Radical Formation: Addition
Radicals can be formed by adding a radical to a spin-paired molecule. This is typically observed with unsaturated species, where the addition of a radical across the π bond leads to the production of a new radical by dissolving the π bond. For example, the addition of a Br radical to an alkene yields a carbon-centered radical.
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an unpaired...
Similar to charge conservation in chemical reactions, spin conservation is implicit for radical reactions. Accordingly, the product formed must possess an unpaired...
Radical Reactivity: Intramolecular vs Intermolecular
Radical reactions can occur either intermolecularly or intramolecularly. In an intermolecular radical reaction, a nucleophilic radical adds to an electrophilic alkene or vice versa. In such reactions, the radical and generally the alkene, which is also called the radical trap, are two different molecules. Additionally, for such intermolecular reactions to occur, the radical trap must be active, present in an excess concentration, and the radical starting material must have a weak carbon–halogen...


