相关实验视频
Updated: Mar 18, 2026

08:52
Characterizing Electron Transport through Living Biofilms
Published on: June 1, 2018
9.0K
在Arrhenius图中观察到的马库斯钟形电子转移动力学
Morteza M Waskasi1, Gerdenis Kodis1, Ana L Moore1
1School of Molecular Sciences and ‡Department of Physics, Arizona State University , Tempe, Arizona 85287, United States.
Journal of the American Chemical Society
|July 6, 2016
概括
电子转移的马库斯理论预测了一个钟形的速率依赖. 在富勒-氨酸二合体上的实验表明这种速率定律适用于温度变化,而不仅仅是化学变化.
科学领域:
- 物理化学
- 摄影化学
- 电子转移
背景情况:
- 马库斯理论描述了基于反应自由能量的电子转移速率.
- 一个关键的预测是钟形 (反向抛物线) 速率依赖.
- 传统上通过改变分子结构来观察.
研究的目的:
- 通过实验验证马库斯理论对钟形速率依赖性的预测.
- 调查温度变化,而不是化学修饰,可以诱导这种现象.
- 提供一个清晰的证实马库斯的能量缺口法则.
主要方法:
- 研究了一种富勒-二系统.
- 研究了光诱导电子转移和随后的电荷重组.
- 分析电荷重组的速度作为温度的反向函数.
主要成果:
- 观察到电荷重组率与温度的反向依赖.
- 在冷却时的速度增加,然后在较低的温度下降.
- 这种非Arrhenius行为是由于重组和反应自由能量的显著温度变化造成的.
结论:
- 证明温度变化可以诱导马库斯倒置抛物线效应.
- 提供了强有力的实验证据, 马库斯能量差距的法律没有化学变化.
- 突出了温度依赖的重组和反应自由能量在电子转移动学的作用.
相关概念视频
Arrhenius Plots
48.8K
The Arrhenius equation relates the activation energy and the rate constant, k, for chemical reactions. In the Arrhenius equation, k = Ae−Ea/RT, R is the ideal gas constant, which has a value of 8.314 J/mol·K, T is the temperature on the kelvin scale, Ea is the activation energy in J/mole, e is the constant 2.7183, and A is a constant called the frequency factor, which is related to the frequency of collisions and the orientation of the reacting molecules.
The Arrhenius equation can be used...
The Arrhenius equation can be used...
48.8K
Temperature Dependence on Reaction Rate
90.5K
The Collision Theory
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
Atoms, molecules, or ions must collide before they can react with each other. Atoms must be close together to form chemical bonds. This premise is the basis for a theory that explains many observations regarding chemical kinetics, including factors affecting reaction rates.
The collision theory is based on the postulates that (i) the reaction rate is proportional to the rate of reactant collisions, (ii) the reacting species collide in an orientation allowing contact between...
90.5K
Introduction to Enzyme Kinetics
35.7K
Enzyme kinetics studies the rates of biochemical reactions. Scientists monitor the reaction rates for a particular enzymatic reaction at various substrate concentrations. Additional trials with inhibitors or other molecules that affect the reaction rate may also be performed.
The experimenter can then plot the initial reaction rate or velocity (Vo) of a given trial against the substrate concentration ([S]) to obtain a graph of the reaction properties. For many enzymatic reactions involving a...
The experimenter can then plot the initial reaction rate or velocity (Vo) of a given trial against the substrate concentration ([S]) to obtain a graph of the reaction properties. For many enzymatic reactions involving a...
35.7K
Effect of Temperature Change on Reaction Rate
5.3K
The Arrhenius equation,
5.3K
The Integrated Rate Law: The Dependence of Concentration on Time
47.1K
While the differential rate law relates the rate and concentrations of reactants, a second form of rate law called the integrated rate law relates concentrations of reactants and time. Integrated rate laws can be used to determine the amount of reactant or product present after a period of time or to estimate the time required for a reaction to proceed to a certain extent. For example, an integrated rate law helps determine the length of time a radioactive material must be stored for its...
47.1K
E2 Reaction: Kinetics and Mechanism
13.1K
SN2 substitutions and E2 eliminations of alkyl halides proceed via a concerted pathway. While the nucleophile attacks the alpha carbon in SN2 reactions, it functions as a strong base and abstracts a beta hydrogen in the E2 mechanism. The rate-limiting transition state in E2 elimination reactions is characterized by partially broken carbon–hydrogen and carbon–halogen bonds and a partially formed pi bond between the alpha and beta carbons. The beta hydrogen and halide are eliminated...
13.1K

