Potential-energy surfaces and their dynamic implications

Abstract

Accurate density functional and abinitio calculations have been performed to study the potential-energy surfaces (PESs) and their implications for kinetics and dynamics of: (1) the spin-forbidden reaction CH(²Π) +N₂→HCN+N(⁴S); PES characteristics are calculated and used to evaluate the overall rate using non-adiabatic transition-state theory. (2) Gas-phase ion–molecule reactions: C₂H₂⁺+NH₃; PESs are calculated and the mechanism of efficient charge transfer and proton transfer competing with stable complex formation is discussed. C₂H₂⁺+CH₄; the mode-enhancement effect has been elucidated in terms of the new transition state and by direct trajectory calculations.

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