相关实验视频
Updated: Jun 4, 2025

10:37
Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
8.9K
电荷转移能量通过双极时刻
Javier Carmona-Espíndola1, Anaid Flores2, Joel Ireta2
1Departamento de Química, CONAHCYT-Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael Atlixco 186, Ciudad de México 09340, Mexico.
The Journal of chemical physics
|December 17, 2024
概括
这项研究引入了一种新的方法,使用分子二极点来准确计算电荷转移能量贡献,避免随意的群体分析和计算化学中的基准依赖性. 该方法为相互作用能量和激发提供了强大可靠的结果.
科学领域:
- 计算化学计算化学
- 量子化学 是一个量子化学.
- 理论化学 理论化学
背景情况:
- 电荷转移能量是总相互作用能量的一个有争议的组成部分.
- 目前的方法依赖于人口分析,导致任意和依赖基数组的结果.
- 空间分区方法消除了基础集合的依赖性,但仍然涉及任意的空间划分.
研究的目的:
- 开发一个可靠的方法来计算电荷转移能量贡献.
- 消除对人口分析和基数大小的依赖.
- 用分子二极极矩作为无电荷转移系统的参考.
主要方法:
- 约束双极时刻密度函数理论的方法.
- 使用缺乏电荷转移或偏振的参考二极子时刻.
- 计算13个非共价复合体的电荷转移能量贡献和总相互作用能量.
- 确定两个长距离的电荷转移激发.
主要成果:
- 计算的电荷转移能量贡献和激发能量与希尔什菲尔德方法非常一致.
- 约束双极时刻结果独立于人口分析.
- 该方法证明了对不同的电荷传输强度和基础集大小的稳定性.
结论:
- 分子二极极矩作为定义无电荷转移系统的可靠参考.
- 这种新方法克服了现有方法的局限性,提供了准确和一致的结果.
- 该方法在计算化学中计算电荷转移相互作用方面取得了重大进展.
相关概念视频
Induced Electric Dipoles
4.2K
A permanent electric dipole orients itself along an external electric field. This rotation can be quantified by defining the potential energy because the external torque does work in rotating it. Then, the potential energy is minimum at the parallel configuration and maximum at the antiparallel configuration. While the former is a stable equilibrium, the latter is an unstable equilibrium.
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
4.2K
Electric Dipoles and Dipole Moment
5.0K
Consider two charges of equal magnitude but opposite signs. If they cannot be separated by an external electric field, the system is called a permanent dipole. For example, the water molecule is a dipole, making it a good solvent.
Theoretically, studying electric dipoles leads to understanding why the resultant electric forces around us are weak. Since electric forces are strong, remnant net charges are rare. Hence, the interaction between dipoles helps us understand electrical interactions in...
Theoretically, studying electric dipoles leads to understanding why the resultant electric forces around us are weak. Since electric forces are strong, remnant net charges are rare. Hence, the interaction between dipoles helps us understand electrical interactions in...
5.0K
IR Spectrum Peak Intensity: Dipole Moment
651
The dipole moment of a bond is the product of the partial charge on either atom and the distance between them. Dipole moments influence the efficiency of IR absorption and the peak intensity. When a bond with a dipole moment is placed in an electric field, the direction of the field determines if the bond is compressed or stretched. Electromagnetic radiation consists of an electric field component that rapidly reverses direction. It follows that polar bonds are alternately stretched and...
651
Energy Associated With a Charge Distribution
1.5K
The work done to bring a charge through a distance r is given by the potential difference between the initial and the final position. To assemble a collection of point charges, the total work done can be expressed in terms of the product of each pair of charges divided by their separation distance, defined with respect to a suitable origin. Solving this expression gives the energy stored in a point charge distribution.
1.5K
Potential Due to a Polarized Object
365
A neutral atom consists of a positively charged nucleus surrounded by a negatively charged electron cloud. When placed in an external electric field, the external electric force pulls the electrons and nucleus apart, opposite to the intrinsic attraction between the nucleus and the electrons. The opposing forces balance each other with a slight shift between the center of masses of the nucleus and the electron cloud, resulting in a polarized atom. On the other hand, a few molecules, like water,...
365
Calculations of Electric Potential II
1.6K
An electric dipole is a system of two equal but opposite charges, separated by a fixed distance. This system is used to model many real-world systems, including atomic and molecular interactions. One of these systems is the water molecule, but only under certain circumstances. These circumstances are met inside a microwave oven, where electric fields with alternating directions make the water molecules change orientation. This vibration is equivalent to heat at the molecular level.
Consider a...
Consider a...
1.6K

