How to combine the if and run command

Hello:

   Recently I performed a simulation and I'd like to implement a conditional run-command. In a NVE emsemble simulation, I want to stop the running when the the maximal kinetic energy of atoms in the system is less than 1 eV and turn to the next fix simulation. I have no idea how to combine the if and run command as I tried this “run 100000 every 1000 if ***”, but it didn’t work. So could you give me some suggestions how to realize this. Thanks.

2011-11-25