Molecular dynamics simulation of a slab of water in contact with vacuum. The water model is TIP4P/2005. The surface tension is measured from the difference between the stresses normal and parallel to the liquid-vapour interface. This video has been made with this script.
Execute the input.lammps file using LAMMPS. Visualize the dump file using VMD, and extract the temperature and surface tension from the two data files.
If you are new to LAMMPS, you can find tutorials and instructions here.
Feel free to contact me by email if you have inquiries. You can find contact details on my personal page.