Predicting New Pathways for the Reaction CN + C₂H₂

Isocyanoacetylene and cyanoacetylene formation study from C2H2 + CN reaction

“…The reaction of the acetilene with cyano radical may lead to the formation of the int1c complexes (−222.1 $$\rm kJ\,mol^{-1}$$), when the acetylene molecule is attacked by the carbon atom of the cyano radical, and to the nc‐int1c complex (−127.7 $$\rm kJ\,mol^{-1}$$), when acetylene is attacked by the nitrogen atom. These values are about 19.9–20.3 $$\rm kJ\,mol^{-1}$$ above other values found in the literature 3,12 . This amount of energy can be partially explained by the basis set the choice of the basis set and the respective level of calculation theory 22 .…”

“…We have performed improved ab initio calculations to get our PES with the possible pathways in producing HCCNC and HC 3 N from C 2 H 2 + CN reaction. Unlike what was performed in a previous study, 12 we calculate the initial equilibrium geometries of the reactions, common reactions, transition states, and product to get our PES via the M06L functional followed by a single point CCSD(T,full) method and aug‐cc‐pCVTZ basis set for all species involved in this reaction. The rate constants were calculated using the master equation software package MESMER.…”

“…These values are about 19.9-20.3 kJ mol −1 above other values found in the literature. 3,12 This amount of energy can be partially explained by the basis set the choice of the basis set and the respective level of calculation theory. 22 In Ref.…”

“…The HC 3 N has been investigated for many years by both experimental and theoretical studies, but its less stable isomer, isocyanoacetylene, has not received too much attention. However, in the literature [2][3][4]9,12 one finds some theoretical studies with respect to the formation of the HCCNC mechanism. The HC 3 NH + radical recombines with an electron leading to the breaking of the chemical bonds and the HC 3 N, HNC 3 , and HCCNC are all products of the dissociative recombination of the HC3NH + : HC 3 NH + + e ⟶ HC 3 N + H ⟶ HCCNC + H ⟶ HCNCC + H ⟶ HNC 3 + H.…”

“…The possible pathways for this reaction were previously studied elsewhere 12 where the potential energy surface (PES) was obtained within 6-311++g(d,p) basis set with the M06L functional level. 13 In spite of the achievement of the relatively good agreement with respect to other works, 3,4 the energy improvement using the CCSD(T) method 14 was not performed.…”