Watery first steps

US chemists have observed the very first steps of water condensation using high resolution atomic force microscopy (AFM) of water on a flat mica surface with a layer of the carbon material graphene covering the water. The graphene prevents the AFM tip from nudging the water molecules around the surface and so allowed the Caltech team, led by Jim Heath, to get a close-up view of tiny ice crystals forming as water first condenses on a surface quickly followed by a build-up of liquid water. The technique could have wide application in adsorbate structure determination.