Kinetic Study on the Isomerization and Decomposition of the Alkenyl Radicals of 2,4,4-Trimethyl-1-pentene

The pressure- and temperature-dependent
rate coefficients
for the isomerization and decomposition of alkenyl radicals of 2,4,4-trimethyl-1-pentene
(JC8H16) were obtained using the RRKM/ME method.
The potential energy surfaces (PESs) were calculated at the DLPNO-CCSD/CBS//M06-2X/6-311G­(d,p)
level. Uncertainty analysis of dominant reactions was conducted. In
addition, the Metcalfe model was modified using our calculated rate
coefficients. As shown by the results, isomerization reactions are
dominant over the low-to-intermediate temperature range, while decomposition
reactions are significant above 1400 K. Pressure has a significant
effect on the radical stabilization reaction. With an increase of
pressure, the formation of JC8H15-C from JC8H15-A becomes more important. Finally, the updated
rate coefficients have little effect on simulated ignition delay times.
However, the modified mechanism could provide more reasonable flux
in the low-to-high temperature range.