相关实验视频
Updated: Jun 7, 2025

09:02
Rapid PCR Thermocycling using Microscale Thermal Convection
Published on: March 5, 2011
22.7K
在任何温度下反应速率的半古典实时理论:严格的实时导出如何解决交叉温度问题
1Simons Center for Computational Physical Chemistry, New York University, New York, New York 10003, USA and Department of Chemistry, New York University, New York, New York 10003, USA.
The Journal of chemical physics
|November 13, 2024
概括
这项研究引入了化学反应速率的严格半古典理论,将瞬间理论扩展到低温之外. 新方法准确地模拟了在所有温度下穿过障碍物的道,简化了复杂的计算.
科学领域:
- 化学物理 化学物理
- 量子力学就是量子力学.
- 理论化学 理论化学
背景情况:
- 瞬间理论将道速率与周期性的古典轨迹联系起来.
- 标准实时理论仅限于在交叉点以下的温度.
- 现有的方法在温度依赖的速率计算方面遇到了困难.
研究的目的:
- 开发一个严格的半古典理论反应速率有效在所有温度.
- 克服标准实时理论的局限性.
- 提供计算可访问的方法来计算道开通率.
主要方法:
- 结合布莱斯坦的方法,以实现均的非对称扩张.
- 采用了理查森流量相关函数的实时修改.
- 使用了第一原则,第一原则的方法.
主要成果:
- 开发了一种适用于所有温度的理论,平稳地连接低温和高温制度.
- 该理论仍然是可计算的,类似于标准的实时理论.
- 在模型系统中表现出卓越的数值准确性.
结论:
- 新理论提供了一个统一而准确的道挖掘率描述.
- 它比以前的实时理论扩展提供了优势.
- 该框架允许未来的理论进步,包括多轨道贡献.
相关概念视频
Temperature Dependence on Reaction Rate
81.2K
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...
81.2K
Thermal Sigmatropic Reactions: Overview
2.1K
Sigmatropic rearrangements are a class of pericyclic reactions in which a σ bond migrates from one part of a π system to another. These are intramolecular rearrangements where the total number of σ and π bonds remain unchanged.
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
Sigmatropic shifts are classified based on an order term [i, j ], where i and j indicate the number of atoms across which each end of the σ bond migrates. Below are examples of a [3,3] sigmatropic shift in...
2.1K
Reaction Mechanisms
25.5K
Chemical reactions often occur in a stepwise fashion, involving two or more distinct reactions taking place in a sequence. A balanced equation indicates the reacting species and the product species, but it reveals no details about how the reaction occurs at the molecular level. The reaction mechanism (or reaction path) provides details regarding the precise, step-by-step process by which a reaction occurs.
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
For instance, the decomposition of ozone appears to follow a mechanism with two steps:
25.5K
Effect of Temperature Change on Reaction Rate
4.0K
The Arrhenius equation,
4.0K
Predicting Reaction Outcomes
8.2K
Kinetics describes the rate and path by which a reaction occurs. In contrast, thermodynamics deals with state functions and describes the properties, behavior, and components of a system. It is not concerned with the path taken by the process and cannot address the rate at which a reaction occurs. Although it does provide information about what can happen during a reaction process, it does not describe the detailed steps of what appears on an atomic or a molecular level. On the other hand,...
8.2K
Reaction Rate
51.4K
The rate of reaction is the change in the amount of a reactant or product per unit time. Reaction rates are therefore determined by measuring the time dependence of some property that can be related to reactant or product amounts. Rates of reactions that consume or produce gaseous substances, for example, are conveniently determined by measuring changes in volume or pressure.
The mathematical representation of the change in the concentration of reactants and products, over time, is the rate...
The mathematical representation of the change in the concentration of reactants and products, over time, is the rate...
51.4K

