Probing the [CoC2H6](+) potential energy surface: A detailed guided-ion beam study

The potential energy surface for the CoC2H6+ system is probed by using a guided-ion beam tandem mass spectrometer in conjunction with a de discharge/flow tube ion source. Bimolecular reactions of Co+ + C2H6, Co+-(C2H4) + H-2 (D-2), and CoCH2+ + CH4 (CD4) are examined, as well as threshold collisional activation of Co+(C2H6) and Co+(C2H4) with Xe. The results allow details of the [CoC2H6](-) potential energy surface (PES) to be elucidated. Key features of the PES include barrier heights of 1.04 +/- 0.11 eV (0.29 +/- 0.09 eV in excess of the endothermicity) for the reaction of Co+ with ethane to form CoCH2+ + CH4 and of 0.32 +/- 0.12 eV for the exothermic reaction to form Co+(C2H4) + H-2. From the collisional activation studies, we determine 0 K bond dissociation energies for Co+-C2H4 and Co+-C2H6 complexes of 1.86 +/- 0.07 and 1.04 +/- 0.05 eV, respectively, in good agreement with literature values. D-0(DCo+-C2H4) = 1.13 +/- 0.16 eV is also determined although it is somewhat more speculative.