[lammps-users] No fix, No move?

Hi, everyone,
If I don’t want any ensemble(like NVT, NVE, NPT) to constraint my system and just want to use the 2nd Newton law to update position and velocity, what am I going to do? How about giving a pulse laser in a span time?

thanks

Hi, everyone,

If I don't want any ensemble(like NVT, NVE, NPT) to constraint my
system and just want to use the 2nd Newton law to update position

this _is_ NVE.

axel.

Dear Xiaopeng

When you say that you want Newton’s 2nd law to update position/velocity, you should use NVE as they are constant energy simulation.
In a isolated system, total energy should be constant. So, whatever initial structure you start with, it would have certain potential energy. During the nve run, a part of that energy will get transformed into KE (depending upon forces on atoms) and which will everntially change the potential energy. System will equilibrate itself at desired temperature depending upon your initial configuration and hence energy.

P.S. Seems like Axel put in short. :slight_smile:

2008/10/22 Xiaopeng Huang <[email protected]…127…>