Abstract
The potential energy surface (PES) for the formation of C4H 4•+ from the pyridine radical cation by loss of HCN was determined from quantum chemical calculations using the G3//B3LYP method. The complete reaction pathways for the formation of the low-energy C 4H4•+ isomers, radical cations of methylenecyclopropene (MCP•+), vinylacteylene (VA •+), cyclobutadiene, and butatriene were obtained. Based on the PESs, a Rice-Ramsperger-Kassel-Marcus model calculation was performed to investigate the dissociation kinetics. The calculated dissociation rate constants agreed with the previous experimental data. It was predicted that a mixture of MCP•+ and VA•+ was formed by loss of HCN. The formation of MCP•+ was more favored near the dissociation threshold and at high energies, whereas the formation of VA •+ was more favored at the low energies corresponding to the ion lifetime of microseconds.
Original language | English |
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Pages (from-to) | 3087-3094 |
Number of pages | 8 |
Journal | Journal of Physical Chemistry A |
Volume | 115 |
Issue number | 14 |
DOIs | |
State | Published - 14 Apr 2011 |