Modelling Interstellar Chemistry:
Why do Carbon Compounds Dominate the Observed Gas Phase Species?
 
Flavio Scappini^* and William Klemperer^{**
         *}scappini@astbo1.bo.cnr.it
        ^**billk@midas.harvard.edu
Department of Chemistry
Harvard University, Cambridge MA 02138, USA

We discuss molecule formation with a view towards treating the question of excess oxygen. We will discuss the stability of gas phase and solid phase species in the radiation fields that exist. We will also discuss molecular emission and high-energy molecular processes, in stellar envelopes.