A joint diffusion/collision model for crystal growth in pure liquid metals

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Chemistry

Background:

• Solidification theory relies on understanding atomic attachment kinetics at liquid/solid interfaces.
• A key unresolved question is whether atomic growth in pure liquid metals is thermally activated.

Purpose of the Study:

• To investigate the thermal activation requirements for atomic attachment in pure liquid metals.
• To develop and validate a model for predicting solidification growth kinetics.

Main Methods:

• Utilized molecular dynamics simulations to model atomic behavior at interfaces.
• Employed machine learning techniques to analyze simulation data.
• Developed a joint diffusion/collision model to describe growth mechanisms.

Main Results:

• Demonstrated that a significant fraction of atoms at Aluminum interfaces (Al(111), (110), (100)) require thermal activation for attachment.
• Showed that other atoms attach to the crystal lattice without an energy barrier.
• Validated the joint diffusion/collision model's ability to predict general metal growth behavior.

Conclusions:

• The study provides quantitative descriptions of temperature-dependent growth kinetics.
• The findings offer new insights into solidification theory and experimental observations.
• The model is applicable to phase change materials and lithium dendrite growth in batteries.