The reaction of oxygen atoms O(P-3) with unsaturated nitriles (RCN), v
iz. acrylonitrile (CH2=CHCN), and crotononitrile (CH3CH=CHCN), was stu
died in a flow discharge tube in the pressure range 1.2-1.7 Torr using
the O(P-3) chemiluminescence titration method. The rate constants for
the reaction O(P-3)+RCN-->products was determined at room temperature
to be (4.9+/-1.0)x10(-13) and (5.4+/-0.8)x10(-13) cm(3) molecule(-1)
s(-1) for acrylonitrile and crotononitrile respectively. The activatio
n energies for the above reactions were estimated using the MNDO metho
d. The formation of a biradical involving the addition of an oxygen at
om to the double bond is proposed as the major channel for the reactio
n. (C) 1997 Elsevier Science B.V.