The Formation of Complex Interstellar Molecules

  • A. Dalgarno
Part of the Physics of Atoms and Molecules book series (PAMO)


A rich array of complex molecules has been detected in interstellar space. Table 1 is a list arranged in order by the number of atoms contained in the molecule. For the complex organic species the abundances relative to hydrogen are of the order 10−8∓1010 or less. The abundances vary from one interstellar cloud to another. In TMC-1 there are observed high abundances of cyanopolyynes and complex hydrocarbons, whereas in SGR B2 oxygen-bearing organic molecules appear to be relatively enhanced. In the Orion molecular cloud, large variations occur which are associated with high velocity outflows from embedded young stars. Various attempts have been made to construct theoretical models of the formation and destruction of interstellar molecules. We review them here with particular reference to molecular species containing several carbon atoms.


Polycyclic Aromatic Hydrocarbon Abundance Ratio Dense Cloud Interstellar Cloud Dissociative Recombination 
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Copyright information

© Plenum Press, New York 1987

Authors and Affiliations

  • A. Dalgarno
    • 1
  1. 1.Harvard-Smithsonian Center for AstrophysicsCambridgeUSA

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