在环境条件下在纯水中进行质子转移的微观机制
Jun Huo1, Jianghao Chen1,2, Pei Liu3
1Kuang Yaming Honors School, Nanjing University, Nanjing 210023, China.
Journal of chemical theory and computation
|June 27, 2023
概括
在纯水中的质子转移 (PT) 在 (H3O+) 和氧化物 (OH-) 离子之间有显著差异. 模拟揭示了不同的结构,特性和转移机制,解释了水的结构,特性和转移机制.
科学领域:
- 计算化学和凝聚物质物理.
- 研究分子动力学和量子力学的原理.
背景情况:
- 质子转移 (PT) 在化学和生物系统中至关重要.
- 在纯水中研究PT是具有挑战性的,因为自离电常数很低.
- 之前的研究重点是酸性/性溶液,而不是纯水.
研究的目的:
- 模拟和理解纯水中的质子转移机制.
- 阐明水中 (H3O+) 和氧化物 (OH-) 离子的不同行为.
- 为水系统中 PT 过程提供微观解释.
主要方法:
- 使用一个神经网络潜力 (NNP) 与量子力学准确度.
- 在较长时间内进行大规模 (1000个分子) 分子动力学模拟.
- 训练NNP进行MP2级计算,考虑电子相关性.
主要成果:
- 和氧化离子表现出不同的水化结构和特性.
- 氧化离子形成更稳定的水合结构,具有更高的PT能量障碍.
- 质子转移机制不同:与OH相关的PT较少发生,而H3O+PT则涉及循环或链条模式中的多个分子.
结论:
- 这项研究为纯水中的质子转移提供了详细的显微镜解释.
- 阐明了H3O+和OH-离子的明显的PT行为.
- 模拟的大小和持续时间对于水PT研究的准确结果至关重要.
更多相关视频
05:51Isotopic Effect in Double Proton Transfer Process of Porphycene Investigated by Enhanced QM/MM Method
Published on: July 19, 2019
6.3K
10:52Multiscale Sampling of a Heterogeneous Water/Metal Catalyst Interface using Density Functional Theory and Force-Field Molecular Dynamics
Published on: April 12, 2019
12.9K
相关概念视频
Water: A Bronsted-Lowry Acid and Base
50.7K
The reaction between a Brønsted-Lowry acid and water is called acid ionization. For example, when hydrogen fluoride dissolves in water and ionizes, protons are transferred from hydrogen fluoride molecules to water molecules, yielding hydronium ions and fluoride ions:
50.7K
ATP Driven Pumps I: An Overview
8.3K
ATP-driven pumps, also known as transport ATPases, are integral membrane proteins. They have binding sites for ATP located on the membrane's cytosolic side and the ion-conducting domain in the transmembrane region. These pumps use the free energy released from ATP hydrolysis to move the solutes across cell membranes against an electrochemical gradient.
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
There are four main types of ATP-driven pumps - P-type, V-type, F-type, and ABC transporter. All these pumps are of varying complexities and...
8.3K
Solubility Equilibria: Ionic Product of Water
1.0K
Pure water is a weak electrolyte; only a small amount ionizes into hydrogen and hydroxide ions. At any given temperature, the concentration of undissociated water is almost constant, so the ionic product of water is the product of the hydrogen and hydroxide ion concentrations, denoted as Kw. The square root of Kw gives the individual ion concentrations.
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...
The ionic product of water varies with temperature, and its value is 1.0 x 10−14 at standard experimental conditions. Per Le...
1.0K
¹H NMR of Labile Protons: Deuterium (²H) Substitution
927
This lesson illustrates the role of deuterium substitution in simplifying the NMR spectrum of compounds comprising labile protons. One method employed is the use of deuterium. Amongst the three isotopes of hydrogen, deuterium (2H) has a nucleus composed of one proton and one neutron. When the D2O solvent is added to a pure dry ethanol solution, its labile proton is substituted with deuterium.
927
Proton (¹H) NMR: Chemical Shift
1.8K
Organic molecules primarily contain carbon and hydrogen atoms. While all the hydrogen isotopes are NMR-active, protium or hydrogen-1 is the most abundant. It has a significant energy separation between its nuclear spin states due to its large gyromagnetic ratio. As per Boltzmann's distribution, an increase in the energy separation implies a greater excess population of nuclei available for excitation, resulting in a strong NMR absorption signal.
Absorption signals of all the protium nuclei...
Absorption signals of all the protium nuclei...
1.8K
Aquaporins
4.9K
Aquaporins or AQPs are a family of integral membrane proteins whose primary function is to transport water, while some called aquaglyceroporins also transport glycerol. In addition, aquaporins have also been suspected to be involved in transporting volatile substances, such as carbon dioxide and ammonia, across membranes. Such AQPs that act as gas channels are often highly expressed in cells involved in the gaseous exchange, such as red blood cells, epithelial cells, and pulmonary capillaries.
4.9K
