The ion-neutral reactions of the C₂H₂N⁺ cation with C₂H₂ have been investigated using a Guided Ion Beam Mass Spectrometer (GIB-MS). The following ionic products were observed: CH₃⁺, C₂H₂⁺, C₂H₃⁺, HNC⁺/HCN⁺, HCNH⁺, C₃H⁺, C₂N⁺, C₃H₃⁺, HCCN⁺ and C₄H₂N⁺. Theoretical calculations have been carried out to propose reaction pathways leading to the observed products. These processes are of relevance for the generation of long chain nitrogen-containing species and they may be of interest for the chemistry of Titan’s ionosphere or circumstellar envelopes.

The current study was undertaken to probe the ionic products of the ion-neutral reaction of C2H2N+ with CH4 using guided ion beam mass spectrometry (GIB-MS) in which the CH3+, C2H3+, HCNH+, C2H5+, C2H3N+ and C3H4N+ ions are identified as products. Theoretical calculations were performed to suggest reaction pathways leading to the detected products. These processes might be of relevance for the generation of long chain carbon-nitrogen bearing compounds in Titan's atmosphere, the interstellar medium or circumstellar envelopes.

In this study we report theoretical and experimental evidence for the formation of ionic products by the ion-neutral reaction of C2H2N+ with C2H6. Our investigations consist of laboratory measurements using a guided ion beam mass spectrometer together with complementary ab initio quantum chemical computations, at the MP2/6-311++G(d,p) level of theory, in order to elucidate the energetics and geometries of the intermediates and transition states that are involved in the production of the observed product ions. This study also provides insights on the isomeric nature of the observed product ions, their formation pathways together with collision energy and pressure dependences. The experimental data agrees well with the predictions of the ab initio calculations. Despite data provides evidence for the occurrence of C2H5+ as the most salient product ion, the production of CH3+, C2H3+, C3H5+, C3H7+ and C2H4N+ is also evident. A reaction scheme was proposed to elucidate the mechanisms responsible for the formation of the observed product ions. These processes might be intermediate steps in the generation of long chain carbon and nitrogen-bearing compounds in Titan's ionosphere, the interstellar medium or circumstellar envelopes.

The gas phase reactivity of C₂H₂N⁺ with C₂H₄ is studied using a combined experimental and theoretical approach through guided ion beam mass spectrometry (GIB-MS) and ab initio calculations. Results indicate the formation of C₃H₅⁺, C₂H₄⁺, C₄H₅N⁺ and C₃H₃⁺ as major products, in addition to minor generation of C₂H₃⁺, C₂H₄N⁺, C₄H₄N⁺, C₃H₂N⁺, and CH₃⁺. Theoretical calculations show that reaction proceeds via formation and subsequent rearrangements of a [C₄H₆N]⁺ adduct. In the quest to probe its singlet electronic state hypersurface, the most relevant stationary points along the reaction pathway leading to the various products are located and optimized. The results of our calculations at the MP2/6-311++G(d,p) level were found to be in agreement with our experimental findings, as well as with the derived enthalpies of reaction for the designated reaction channels. The present study provides substantial new insights on the formation of complex organics in Titan’s ionosphere detected by the Ion and Neutral Mass Spectrometer (INMS) onboard the Cassini spacecraft. These pathways might also be of relevance for the generation of long chain carbon-nitrogen bearing compounds in low-temperature environments e.g. the interstellar medium or circumstellar envelopes.