Deuterium Fractionation in Interstellar Clouds

  title={Deuterium Fractionation in Interstellar Clouds},
  author={Tom J. Millar},
  journal={Space Science Reviews},
  • T. Millar
  • Published 1 April 2003
  • Physics
  • Space Science Reviews
This paper reviews the chemical processes responsible for fractionating deuterium in interstellar molecules. I show that this process is intrinsically a low temperature phenomenon and discuss how the degree of enhancement of the deuterium content of molecules is related to the physical conditions, particularly abundances, in molecular clouds. If significant amounts of abundant species, such as CO, are frozen out on to interstellar dust grains, the resulting enhancement in H2D+ can result in its… 
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