Hello everyone! I’m trying to simulate the motion of particles in a granular system. First I define the “dimension” to be 2, I make a box whose length in Z direction is much shorter than in X and Y direction. Then I used the “fix pour” command to pour particles in. The code can run but I cannot see any particle in OVITO. I check the dump file, and find that coordinate of all parti…

Hello, I run a simple system with two groups, top and bottom. The displacement of all atoms is limited by the “fix spring/self” command: fix 1 all spring/self 6.7867 And I want to compute the mean square displacement of the two groups with the “compute msd” command. Everything goes as expected when I run the input file, and a restart file is saved…

I would like to impose the total pressure (i.e., [Pxx+Pyy+Pzz]/3) on my simulation with one of the box lengths fixed. Theoretically, what I want is something like fix 3 all press/berendsen y ${targetP} ${targetP} ${pdamp} z ${targetP} ${targetP} ${pdamp} couple xyz This does not work as it is an illegal pressure configuration. Another idea was to use: variable lenX equal lx f…

I found that fix balance and energy minimization can’t be used simultaneously, is it really ? Why ? If I want to optimize the CPU, how can I minimize the energy ？ 1 post - 1 participant Read full topic

Hi, I installed 29 Sep 2021 LAMMPS version on Ubuntu with: sudo apt-get install lmp Now, I have some problem on recalling pair_style reaxff. I get an error: Unrecognized pair style ‘reaxff’ is part of the REAXFF package which is not enabled in this LAMMPS binary. (src/force.cpp:278) First, I tried lmp -help to see supported command lines, and unfortunately reaxff was not …