Add new reactions using chemmech

Hi everyone,

I am using chemmech to add new reactions to the existing mechanism. One of the reactions i want to add is:

The reaction rate constant is given as k0 and kinf. However, i went over the guide for writing reaction rate constant. There is no such rate constant format (the types of reaction rate constant are given in the below picture).

Can anyone help with formating this rate constant!

The nature of problem is unclear. Please reply with the formula that you wish to use to calculate the rate constant.