[lammps-users] Problem with temper command

I am trying to use parallel tempering and I am getting the following error, the lmp executable works fine with other commands. Please help.

COMMAND:
temper 40000 50 $t tempfix 0 45322
variable t world 0.9 1.0 1.1 1.2

ERROR:
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0[cli_0]: aborting job:
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 0
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 2[cli_2]: aborting job:
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 2
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 3[cli_3]: aborting job:
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 3
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 1[cli_1]: aborting job:
application called MPI_Abort(MPI_COMM_WORLD, 1) - process 1

I would try to see if you can run the individual simulations (at various
temperatures) without error. Tempering kind of removes you one
stage from those, so you might not be seeing errors generated at
a lower level.

Steve