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… 
Formation and stability of cubic ice in water droplets.
  • B. Murray, A. Bertram
  • Environmental Science, Physics
    Physical chemistry chemical physics : PCCP
  • 2006
Using X-ray diffraction, the formation of cubic ice in pure water droplets suspended in an oil matrix as a function of droplet size is studied, showing that droplets of volume median diameter 5.6 microm froze dominantly to cubic ice with stacking faults, supporting previous suggestions that cubic ice is the crystalline phase that nucleates when pure water Droplets freeze homogeneously at approximately 235 K.
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Microphysics and heterogeneous chemistry of polar stratospheric clouds.
  • T. Peter
  • Environmental Science, Physics
    Annual review of physical chemistry
  • 1997
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