Hard sphere

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1

Hey Meisam,

I think you can get a good result by tweaking the lj interaction to make it behave similar to a hard sphere, i.e. steeper repulsion over shorter cutoff and kill off the attaractive part.

Good luck.

HK

 

> Dear All, 
> 
> LAMMPS can support Hard sphere? 

No. 

> (I want to simulate a system that have spheres with different sizes and there is no interaction between them). If yes, how? 
> 
> Thanks, 
> Meisam 
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2

Hey Meisam,

I think you can get a good result by tweaking the lj interaction to make it
behave similar to a hard sphere, i.e. steeper repulsion over shorter cutoff
and kill off the attaractive part.

hadi,

that is not the same thing. no matter how steep you make
your LJ potential it will always be "soft" and the steeper
you make it, the shorter the time step will have to be and
thus it will be _very_ inefficient.

to do a _real_ hard sphere simulation, you have to write
a new integrator that can track collisions and adjust trajectories
after the fact accordingly. it is somewhat similar to what
is done in the granular package, but those are still "soft"
particles.

cheers,
   axel.