一个分子动力学研究在同质和异质核化之间的边界
1BCAST, Brunel University London, Uxbridge, Middlesex UB8 3PH, United Kingdom.
The Journal of chemical physics
|March 1, 2024
概括
经典核化理论 (CNT) 的差异是通过原子模拟来解释的. 光滑的表面通过结构模板促进异质核化,而粗的表面通过波动触发均核化,影响核化动力学.
科学领域:
- 材料科学 材料科学 材料科学
- 物理化学 物理化学
- 计算物理 计算物理
背景情况:
- 经典核化理论 (CNT) 的预测往往与核化动力学的实验和模拟数据有所不同.
- 这种差异使人们对CNT的基本有效性提出了疑问.
- 了解核化机制对于材料合成和加工至关重要.
研究的目的:
- 为了研究液体 (Al) 与无形基质相互作用的核化的原子化机制.
- 阐明基质表面地形 (光滑与粗) 在确定核化路径中的作用.
- 为了解释理论,模拟和实验之间的核化动力学观察到的差异.
主要方法:
- 用分子动力学 (MD) 模拟来建模与无形基板接触的液态Al.
- 模拟专注于分析不同表面条件下的原子结构和核化事件.
- 在同质和异质条件下核化动态的比较.
主要成果:
- 光滑的无形表面通过结构模板机制促进异质核形成.
- 粗的无形表面通过波动机制在较高的低冷却下导致同质核形成.
- 在光滑的表面上,初始核的生长速度明显快于同质核形成.
- 这些发现协调了CNT预测和模拟/实验结果之间的差异.
结论:
- 在同质和异质核化机制之间存在明确的界限.
- 结构模板是异质核形成的一般机制.
- 在没有模板的情况下,通过波动发生同质核化,这可能解释了杂质的作用.
- 这项研究提供了对核化现象,桥梁理论和实验的更深入的理解.
相关概念视频
SN2 Reaction: Kinetics
8.4K
Kinetic Studies and Significance
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
In a chemical reaction, a relationship exists between the concentration of reactants and the rate at which the reaction proceeds. The study to measure this relationship is known as the kinetics of a chemical reaction. Kinetic studies are used to deduce the rate law of a chemical reaction, which provides information about the species involved during the transition state of the rate-determining step. Thus, kinetic studies help to derive the mechanism of a...
8.4K
Crystal Growth: Principles of Crystallization
1.9K
Crystallization is a phase transformation process in which crystals are precipitated from a supersaturated solution or formed from other sources. During crystallization, atoms or molecules arrange themselves into a well-defined, rigid crystal lattice to minimize energy.
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent...
Initiating crystallization involves manipulating the concentration of the solute and the temperature of the solution. Since crystal growth occurs when the ratio of concentration and solubility of the solute in the solvent...
1.9K
Boundary Layer Characteristics
109
When a fluid encounters a solid surface, a boundary layer forms due to the interaction between the fluid's motion and the stationary surface. This phenomenon is characterized by a thin region adjacent to the surface where viscous forces dominate, influencing the fluid's velocity profile. The development of the boundary layer begins at the leading edge of the surface and evolves as the fluid moves downstream.As the fluid flows over the surface, friction between the fluid and the wall slows down...
109
Molecular Orbital Theory II
19.2K
Molecular Orbital Energy Diagrams
19.2K
Comparing Intermolecular Forces: Melting Point, Boiling Point, and Miscibility
44.3K
Intermolecular forces are attractive forces that exist between molecules. They dictate several bulk properties, such as melting points, boiling points, and solubilities (miscibilities) of substances. Molar mass, molecular shape, and polarity affect the strength of different intermolecular forces, which influence the magnitude of physical properties across a family of molecules.
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
Temporary attractive forces like dispersion are present in all molecules, whether they are polar or nonpolar. They...
44.3K
Homogeneous Equilibria for Gaseous Reactions
25.2K
Homogeneous Equilibria for Gaseous Reactions
For gas-phase reactions, the equilibrium constant may be expressed in terms of either the molar concentrations (Kc) or partial pressures (Kp) of the reactants and products. A relation between these two K values may be simply derived from the ideal gas equation and the definition of molarity. According to the ideal gas equation:
For gas-phase reactions, the equilibrium constant may be expressed in terms of either the molar concentrations (Kc) or partial pressures (Kp) of the reactants and products. A relation between these two K values may be simply derived from the ideal gas equation and the definition of molarity. According to the ideal gas equation:
25.2K


