Structural transitions in amorphous water ice and astrophysical implications.

  title={Structural transitions in amorphous water ice and astrophysical implications.},
  author={Peter Jenniskens and D. F. Blake},
Selected area electron diffraction is used to monitor structural changes of vapor-deposited water ice in vacuum during warm-up from 15 to 188 K. A progression of three amorphous forms of water ice is found with well-defined transitions. The formation of a high-density amorphous form (Iah) at 15 K is confirmed, and the transition to the more familiar low-density form (Ial) occurs gradually over the range 38 to 68 K. At 131 K, the ice transforms into a third amorphous form (Iar), which precedes… 

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We employ classical molecular dynamics simulations to investigate the molecular-level structure of water during the isothermal compression of hexagonal ice (I$h$) and low-density amorphous (LDA) ice



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