The formation of cubic ice under conditions relevant to Earth's atmosphere

  title={The formation of cubic ice under conditions relevant to Earth's atmosphere},
  author={Benjamin J. Murray and Daniel A. Knopf and Allan K. Bertram},
An important mechanism for ice cloud formation in the Earth's atmosphere is homogeneous nucleation of ice in aqueous droplets, and this process is generally assumed to produce hexagonal ice. However, there are some reports that the metastable crystalline phase of ice, cubic ice, may form in the Earth's atmosphere. Here we present laboratory experiments demonstrating that cubic ice forms when micrometre-sized droplets of pure water and aqueous solutions freeze homogeneously at cooling rates… Expand

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