I send you my case, prova.in is the simulation control parameter, insteal cipolla is the coordinate file.
fix rigid command works well but rotate around y axis in the xy plane, but this is very strange because the top and the bottom interact via LJ potential. What’s wrong? The distance of equilibrium between top and bottom are 2, so when the distance between top and bottom are less than 2 the energy must be increase and the particle must be repelled at the equilibrium distance.
cipolla (6.74 KB)
prova.in (747 Bytes)