The reactivity of the molecular anion class="mathmlsrc">class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019103516000622&_mathId=si13.gif&_user=111111111&_pii=S0019103516000622&_rdoc=1&_issn=00191035&md5=52fad8475cacdfe9bee59c2222753764" title="Click to view the MathML source">C₃N⁻,class="mathContainer hidden">class="mathCode">${\mathrm{C}}_3{\mathrm{N}}^{-},$ proposed to be abundant in Titan’s ionosphere, is explored.

The kinetics and branching ratios of the class="mathmlsrc">title="View the MathML source" class="mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019103516000622&_mathId=si14.gif&_user=111111111&_pii=S0019103516000622&_rdoc=1&_issn=00191035&md5=fb3ef628573f69cd1794e7b34b1f7d0b">class="imgLazyJSB inlineImage" height="22" width="131" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S0019103516000622-si14.gif">class="mathContainer hidden">class="mathCode">${\mathrm{C}}_3^{15}{\mathrm{N}}^{-}+{\mathrm{HC}}_3^{14}\mathrm{N}$ and class="mathmlsrc">title="View the MathML source" class="mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019103516000622&_mathId=si15.gif&_user=111111111&_pii=S0019103516000622&_rdoc=1&_issn=00191035&md5=97c11d16d928215fa546c3239c324a67">class="imgLazyJSB inlineImage" height="22" width="131" alt="View the MathML source" title="View the MathML source" src="/sd/grey_pxl.gif" data-inlimgeid="1-s2.0-S0019103516000622-si15.gif">class="mathContainer hidden">class="mathCode">${\mathrm{C}}_3^{14}{\mathrm{N}}^{-}+{\mathrm{HC}}_3^{14}\mathrm{N}$ reactions are investigated in the laboratory down to 50 K with the CRESU method.

Proton transfer is the main exit channel which is indistinguishable with non-isotopically labeled reactants.

A minor exit channel, reactive detachment, has been uncovered, although the nature of the neutral products has not been identified.

It is concluded that the class="mathmlsrc">class="formulatext stixSupport mathImg" data-mathURL="/science?_ob=MathURL&_method=retrieve&_eid=1-s2.0-S0019103516000622&_mathId=si16.gif&_user=111111111&_pii=S0019103516000622&_rdoc=1&_issn=00191035&md5=82a3a9ab5e61effcadaf0b3d00453915" title="Click to view the MathML source">C₃N⁻+HC₃Nclass="mathContainer hidden">class="mathCode">${\mathrm{C}}_3{\mathrm{N}}^{-}+{\mathrm{HC}}_3\mathrm{N}$ reaction cannot contribute to the growth of anions in the upper atmosphere of Titan.