quire on lammps

hi sir,
I am Nandlal pingua from IIT kanpur, INDIA new user of LAMMPS.

Question :-

  1. I have a doubts that is what formate should i used for time-step. e.g-either 2*10e-8 or 0.00000002. in both case simulation work results are different so, what formate i will use in time steps? one more thing that, is there important role of time-step in simulation? I have seen if i increase or decrease the time-step in that case one error shown after first iteration all atoms lost. what is reason behind i am not getting.?

  2. In lattice-command, How i will known that which style i will choose for simulation? e.g fcc or bcc or hcp or sc etc

  3. How neighbour list effect the simulation? is it is high or low build

Thank You

Why are you posting the same quest. again?