Title: A new method for calculating the pressure profile by LAMMPS
Presenter: Takenobu Nakamura
Affiliation: Tohoku University WPI-AIMR
Abstract: Different from density or kinetic energy, the computation for local pressure tensor has not been supported by LAMMPS. That is partly because the local pressure tensor is not defined as a “per-atom” quantity but as a result of an interaction among several atoms in a cluster potential. According to the literature 1, the local pressure tensor can be explicitly represented by using a contour integration. Using the representation, we have developed a method to calculate the local pressure tensor along the radial axis for a spherical material 2. Additionally, we have recently developed a method for calculating the 3-dimensional local pressure tensor with high accuracy 3. Our method exactly assigns the contribution of contour integration to each 3D bin without a numerical approximation as in the previous method 4. We have made a new command calculating local pressure field for (1) cuboids divided in a 3 dimensional grid pattern, (2) planar bins sliced along 1 dimensional axis 5, (3) spherical bins sliced along the radial axis from a chosen center. In this talk, after a brief introduction of the theoretical background of the method, we will demonstrate a few application studies. We also show how to use the method in lammps.
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