Hydrogen Formation in the Photolysis of Propyne at 1236 Aring;

摘要

Hydrogen formation in the photolysis of propyne at 1236 Aring; occurs exclusively via a molecular process. The following reactions are energetically possible at 1236 Aring;:CH3Ctrpbnd;CHplus; hngr; rarr;C3H2plus;H2rarr;C3Hplus;Hplus;H2rarr;C3plus;2H2rarr;CHplus;C2Hplus;H2.Photolysis ofCH3Ctrpbnd;CHyields equal amounts of D2and HD; addition of inert gas (C2F6) reduces HD relative to D2. These observations are taken as evidence for participation of the overhyphen;all Process (E) which may be rewritten as follows:CH3Ctrpbnd;CHplus; hngr; rarr;C3HD*plus;D2,C3DH*rarr;C3plus;HD,C3DH*plus;Mrarr;C3DHplus;M.The dissociative lifetime of C3DH*is estimated to be 10minus;10sec assuming unit efficiency for collisional deactivation.