Wien2k

The program package WIEN2k performs electronic structure calculations of solids using density functional theory (DFT). It is based on the full-potential (linearized) augmented plane-wave ((L)APW) + local orbitals (lo) method, one among the most accurate schemes for band structure calculations. Wien2k was developed at the Institute for Materials Chemistry at the Technical University, Vienna.

Wien2k is available on bassi with both serial and parallel versions.

• Setup and Access for Wien2k
• Running Wien2k on bassi
• Running W2web on bassi
• Documentation and Help

Setup and Access for Wien2k

The modules package controls access to software.

To use the default version of Wien2k, include the line:

% module load wien2k

in your .profile.ext or .login.ext files, or type this command whenever you want to access Wien2k for a single session.

Running Wien2k on bassi

A sample job script for k-point parallel execution of Wien2k (modified from the sample at http://www.wien2k.at/reg_user/faq/):

#!/usr/bin/sh
#@ job_type = parallel
#@ output = $(Executable).$(Cluster).$(Process).out
#@ error = $(Executable).$(Cluster).$(Process).err
#@ class = debug 
#@ notification = complete
#@ node = 1
#@ total_tasks = 5
#@ environment= COPY_ALL
#@ network.MPI = sn_all,not_shared,us
#@ wall_clock_limit= 00:30:00
#@ queue

#
echo $LOADL_PROCESSOR_LIST
echo $LOADL_PROCESSOR_LIST > myhosts # _PROCESSOR_LIST where the job will be exec
export np=5; #nbr of PROCESSORS = total_tasks
export k1=35; #kpoint distribution, repeat until k$np
export k2=35;
export k3=35;
export k4=35;
export k5=35;

# generate .machines file
rm -fr .machines
awk ' {for (x=1;x< ENVIRON ["np"]+1;x++) print "k"x":"$x }' myhosts > machines
x=1;
while [ "$x" -le $np ];
do eval z=`echo '$'"k$x"`; grep k$x machines | awk 'BEGIN { FS = ":" } { print $2 }' | sed "s/^/$z:/" >>.machines;
x=$(expr $x + 1);
done
echo "granularity:1" >> .machines
rm -fr machines myhosts

#run your job
run_lapw -ec 0.0001 -p

Please consult with the developers or refer to the Wien2k Users Guide for the fine grained parallel execution. Wien2k on bassi was built with the fine grained parallel execution enabled, but we haven't work out a working job script for it or for the mixed type of parallel execution (k-point and fine grained parallel execution) yet, we will update this website as soon as we have a working job script.

Running W2web

Wien2k on bassi is built with the graphical user interface W2web enabled. To use w2web, you need to use local tunnel. Since bassi doesn't allow a web browser directly point to the port on it, but it allows a given local port to be forwarded to bassi and a port on it through a secure local tunnel.

Please ssh -L 46500:localhost:46600 bassi.nersc.gov, and then upon the login, module load wein2k/2007.2, and then run w2web, it will ask you to pick a port number, which should be 46600. And then point your web browser to http://localhost:46500 (instead of pointing your web browser to bassi.nersc.gov:46600), you should be able to see the startup screen of w2web.

If you use windows, and use F_secure shell client or putty to access bassi, then please use the local tunnel as follows:

Open F-Secure shell client, choose Edit-->settings, it will pop up a new setting window, on that window you click add, it will pop up another small window for you to define your local tunnel: please fill in 46500 to the source port field, 46600 to the destination field, and in the destination host field please fill in bassi.nersc.gov.

It is similar to use local tunnels on putty. On the destination host field you need to fill in bassi.nersc.gov:46600 (there is no separate field for destination port as in F-secure client).

Note: the port numbers 46600 and 46500 here, are just examples, you can choose any number larger than 1024 and less than 65535.

Documentation and Help

The Wien2k Textbooks website has a detailed description of the electronic structure methods available in Wien2k, and a set of technical notes.

The Wien2k Users Manual is particularly useful.