[gmx-users] replica exchange

[Neda Rafiee]

Dear All,
I am doing replica exchange for a peptide in water and I used the following command to run my system:
mpirun -np 4 mdrun_mpi -v -multidir equil[0123] 
but I encountered with an error saying: 
HYDU_create_process (utils/launch/launch.c:75): execvp error on file mdrun_mpi (No such file or directory)
 Can anyone help me find out the problem? 
Thanks