To run ORCA 2.7 in parallel - max. 8 CPUs - it is installed in /apps/orca_x86_64_exe_r2131 First set your mpi enviroment mpi-selector-menu choose 1. openmpi_gcc-1.2.8 and per user You can use script running 8 cpu job: qsub /apps/bin/orca28 input_name If you use your own script your should have: #$ -pe orte 8 ---------------------- and in your input ! PAL8 Be careful and ask queue and program for the same amount of CPUs ---------------------------- Input example ! BP ECP{def2-TZVP,def2-TZVP/J) def2-tzvp def2-tzvp/j tightscf opt ! PAL8 * xyz -2 2 Au 0 0 0 Cl 2.5 0 0 Cl -2.5 0 0 Cl 0 2.5 0 Cl 0 -2.5 0 * To submit job qsub /apps/bin/orca28 input_name