MOLECULAR ORBITAL STUDY OF THE DISSOCIATIVE RECOMBINATION; $HC_{3}NH^{+} + e^{-}$. IS IT POSSIBLE TO PRODUCE ALL OF ISOMERS OF CYANOACETYLENE?

Abstract

The dissociative recombination reaction between $HC_{3}NH^{+}$ and an electron is one of the major route to produe canoacetylene. $HC_{3}N$, in interstellar clouds. We have studied various pathways of this recombination reaction producing $HC_{3}N$ and its isomers, $HNC_{3}$, HCCNC and HCNCC, theoretically. Potential energy surfaces for the processes from neutralized $HC_{3}NH$ are examined by using the ab initio molecular orbital method. The calculated result shows that HCCNC is also produced via the isomerization processes in addition to the products $HC_{3}N$ and HNCCC from the direct hydrogen dissociation. Several product channels $C_{2}H + HNC, C_{2}H + HCN, NH + C_{3}H, CN + C_{2}H_{2}, C_{3} + NH_{2}$ and $C_{3}N + H_{2}$ are shown to be energetically possible based on the thermochemical relationships.