Abstract
Pattern formation of ice crystals during their growth in supercooled water shows a drastic change from a circular disk shape to a well-developed dendritic shape with hexagonal symmetry. Recent experiments for the pattern formation of ice crystal, which were carried out by modern experimental techniques, are summarized. As a result, it is to be emphasized that the anisotropy of inter facial free energy(inter facial tension) around the basal face is negligibly small, while the degree of anisotropy of inter facial kinetic effect increases with the increase of crystal growth velocity. This result means that the hexagonal symmetry of ice dendrite is governed by the inter facial kinetics, instead of the anisotropy of interface free energy.
