Snowflake symmetry mirrors ice crystals’ molecular structure

Measurements of perfect ice crystals have revealed that kinetic parameters controlling the growth of snowflakes from water vapour result in their iconic shape. Now, Mary Jane Shultz from Tufts University, US, and her team have shown that the arrangement of water molecules in ice I_h – the type that forms snowflakes – is directly responsible for the formation of macroscopic six-sided crystals.