由真空-液体界面的原子电离引起的化电子的反应
William A Alexander1, Justin P Wiens, Timothy K Minton
1Department of Chemistry and Biochemistry, Montana State University, Bozeman, MT 59717, USA.
概括
液体表面附近的电子产生反应性D原子. 令人惊的是,许多D原子从糖醇表面逃到真空中,影响了随后的反应.
科学领域:
- 物理化学 物理化学
- 表面科学是一门学科.
- 化学动力学 化学动力学
背景情况:
- 溶解电子是液体中的强化学试剂,能够裂解键并产生像原子这样的反应性物种.
- 了解液体表面的电子化学是至关重要的,因为它因独特的界面条件而不同于散装反应.
研究的目的:
- 为了研究当电子在液体表面附近产生时发生的独特化学反应,特别是糖醇.
- 识别和量化在液体-真空界面上由原子与脱糖醇相互作用形成的产物.
主要方法:
- 液体糖醇 (C(3) D(5) 液体糖醇 (OD) 暴露于一束 (Na) 原子.
- 使用表面敏感技术检测反应产物,包括 (D) 原子,D(2),D(2) O和糖碎片.
主要成果:
- 原子在糖表面有离子,产生与化糖反应的电子.
- 确定的主要产品是D原子,D(2),D(2) O和糖碎片.
- 在与C-D键发生反应之前,显著部分 (43 ± 4%) 的生成的D原子从表面被吸收到真空中.
结论:
- 与散装反应相比,液体表面的电子启动反应产生不同的产物.
- D原子从甘油表面的脱离是一个重要的途径,影响后续的化学过程.
- 这项研究强调了界面现象在控制化学反应性方面的重要性.
相关概念视频
Electrolysis
In a galvanic cell, the electrical work is done by a redox system on its surroundings as electrons produced by the spontaneous redox reactions are transferred through an external circuit. Alternatively, an external circuit does work on a redox system by imposing a voltage sufficient to drive an otherwise nonspontaneous reaction in a process known as electrolysis. For instance, recharging a battery involves the use of an external power source to drive the spontaneous (discharge) cell reaction in...
Solvating Effects
An understanding of the solvating effect helps rationalize the relation between solvation and acidity of the compound. In addition, this also explains the relative stability of conjugate bases for compounds with different pKa values. This lesson details, in-depth, the principle of solvating effects. The strength of an acid and the stability of its corresponding conjugate base are determined using pKa values. This observed relationship is a consequence of solvation, which is the interaction...
Intermolecular Forces in Solutions
The formation of a solution is an example of a spontaneous process, a process that occurs under specified conditions without energy from some external source.
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Such a solution is called an ideal solution. A mixture of ideal gases (or gases such as helium and argon,...
SN1 Reaction: Mechanism
Kinetic studies of ionization of a tertiary halide in a protic solvent suggest that only the substrate participates in the rate-determining step (slow step). The nucleophile is involved only after the slowest step. The SN1 reaction takes place in a multiple-step mechanism.
Firstly, the haloalkane ionizes to generate a carbocation intermediate and a halide ion. This heterolytic cleavage is highly endothermic with large activation energy. The ionization of the substrate, facilitated by a polar...
Firstly, the haloalkane ionizes to generate a carbocation intermediate and a halide ion. This heterolytic cleavage is highly endothermic with large activation energy. The ionization of the substrate, facilitated by a polar...
Energetics of Solution Formation
The formation of a solution is an example of a spontaneous process, which is a process that occurs under specified conditions without energy from some external source.
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Formation of the solution requires the solute–solute and solvent–solvent electrostatic forces to...
When the strengths of the intermolecular forces of attraction between solute and solvent species in a solution are no different than those present in the separated components, the solution is formed with no accompanying energy change. Formation of the solution requires the solute–solute and solvent–solvent electrostatic forces to...
Reduction of Alkynes to trans-Alkenes: Sodium in Liquid Ammonia
Alkynes can be reduced to trans-alkenes using sodium or lithium in liquid ammonia. The reaction, known as dissolving metal reduction, proceeds with an anti addition of hydrogen across the carbon–carbon triple bond to form the trans product. Since ammonia exists as a gas (bp = −33°C) at room temperature, the reaction is carried out at low temperatures using a mixture of dry ice (sublimes at −78°C) and acetone.
When dissolved in liquid ammonia, an alkali metal, such as sodium, dissociates into a...
When dissolved in liquid ammonia, an alkali metal, such as sodium, dissociates into a...


