Whether or not Crystal Growth Needs Thermal Activation in Pure Liquid Metals

The kinetics of atomic attachments at the liquid/solid interface is one of the foundations of solidification theory, and to date a long-standing question remains: whether or not the growth is thermal activated in pure liquid metals. I have resolved this problem by demonstrating a considerable fraction of liquid atoms at the interfaces of Al(111), (110) and (100) need the thermal activation for growth to take place while the others attach to the crystal without energy barrier, using molecular dynamics simulations and machine learning. My joint collision/diffusion model is proved to be robust to predict the general growth behaviours of pure metals. Here, I show this model is able to quantatively describe the temperature dependence of growth kinetics and to properly interpret some important experimental observations, which significantly advances our understanding of solidification theory and also is useful for modelling solidification, phase change materials and lithium dendrite growth in lithium-ion battery.