Quamtum expresso is an integrated suite of computer codes for electronic-structure calculations and materials modeling at the nanoscale. It is based on density-functional theory, plane waves, and pseudopotentials (both norm-conserving and ultrasoft).
Running Quantum Espresso at PDC
To see what versions of Quantum Espresso are available on each machine use the command
module avail espresso
Running on Lindgren
To run on Lindgren you need to first load the gamess module then use aprun to start the exectuable.
module add espresso/4.3 aprun -n 48 qe_pw.x < input_file > output_file
IMPORTANT : You should always use the option disk_io=low on Lindgren. With this option the wave functions are only written at the END of the job rather than after every intermediate step. This will substantially reduce the load on the disk systems and make your job run faster.
Also it is NOT ALLOWED to run the the phonon part of Quantum Espresso (i.e. ph.x) on Lindgren. This is because the phonon part does not seem to have the equivalent of disk_io=low and therefore creates more IO than the shared Lustre system can handle.
Example Job script
#PBS -N myjob # 23 hour wall-clock time will be given to this job #PBS -l walltime=23:00:00 # Number of MPI tasks. #PBS -l mppwidth=96 #ALWAYS ask for full nodes here (even if you do not use all the cores later) #i.e. mppwidth should almost always be a multiple of 24 # Change to the work directory cd $PBS_O_WORKDIR #enable modules within the batch system . /opt/modules/default/etc/modules.sh #load the module module add espresso/4.3 # Run gamess aprun -n 96 qe_pw.x < input_file > output_file