Visual Molecular Dynamics (VMD) is a very good program for viewing all sorts of structure files.


It is free and can be obtained from and installed quite easily.


You will need to register but that won’t result in enormous amounts of spam.


Once installed, it is useful to set the VMDDIR environment variable:


>export VMDDIR=/usr/local/vmd                  # or wherever it happens to be


and include the directory that contains the executable in your path:


>export PATH=$PATH:$VMDDIR/bin


The documentation can be found at the above web site or at $VMDDIR/doc/ug.pdf.


This program can be a bit slow if run across the network or on a machine that is busily calculating something.

If you are calculating on a remote machine, it can be more convenient to download the appropriate files using scp or sftp to your local machine and run vmd locally.