Spherical-Pressure-Tensor

FORTRAN code for calculating local pressure tensor in spherical coordinates.

Files

• Foler /TIP4P_Ice/ contains source code to calculate spherical and planar local pressure tensor profile using TIP4P/Ice model, as described in Ref. 1.
  
• Folder /Hard_sphere/ contains source code used to calculate spherical pressure tensor using hard sphere model, as described in Ref. 2.

Requirement

1). gfortran compiler
2) libgmxfort for reading GROMACS compressed trajectory files (.xtc)

Usage

Compilation

Once installed libgmxfort, FORTRAN code for pressure tensor calculation can be compiled using

gfortran $file -I/usr/local/include `pkg-config --libs libgmxfort`

where /usr/local/include is path to the installed module file. Replace $file with the corresponding file name for FORTRAN code.

Computation parameters

All input parameters for the pressure tensor calculations are set at the beginning of the FORTRAN source code. GROMACS trajectory file (.xtc) and center-of-mass coordinate file for spherical nucleus (CM_True.dat) are needed. "CM_True.dat" file is used to translate the system origin to the center of the nucleus. An example of "CM_true.dat" is provided in the /Hard_sphere/ directory.

Reference

[1] P. Montero de Hijes=, K. Shi=, C. Vega, and C. Dellago, "Comparing the Mechanical and Thermodynamic Definitions of Pressure in Ice Nucleation". to be submitted.
[2] P. Montero de Hijes, K. Shi, E. G. Noya, E. E. Santiso, K. E. Gubbins, E. Sanz and C. Vega, "The Young–Laplace equation for a solid–liquid interface". Journal of Chemical Physics, 153 (2020) 191102. [link][PDF]