  Recent observations have revealed the existence of Complex Organic Molecules
(COMs) in cold dense cores and prestellar cores. The presence of these
molecules in such cold conditions is not well understood and remains a matter
of debate since the previously proposed "warm- up" scenario cannot explain
these observations. In this article, we study the effect of Eley- Rideal and
complex induced reaction mechanisms of gas-phase carbon atoms with the main ice
components of dust grains on the formation of COMs in cold and dense regions.
Based on recent experiments we use a low value for the chemical desorption
efficiency (which was previously invoked to explain the observed COM
abundances). We show that our introduced mechanisms are efficient enough to
produce a large amount of complex organic molecules in the gas-phase at
temperatures as low as 10K.
