摘要
The first cyclic molecule formation reactions from ethyne （C2H2）, initiated by ethynyl radical （C2H）, were studied by theoretical quantum mechanic. The study included the competition reaction between structure re-arrangement for the favourable ring-closure mechanism and ethyne addition in each step. The analysis was done by evaluating the energy difference of activation （AE）, entalphy （AH）, Gibbs （AG） of the optimized stable and transition molecules. The reaction temperatures were set at normal （T = 298 K） and combustion （T = 1200 K） condition.
