[Pw_forum] Constraint on centre of mass of a molecule

[Lorenzo Paulatto]

On Fri, 09 Apr 2010 11:33:00 +0200, Ngoc Linh Nguyen <nnlinh at sissa.it>  
wrote:
> In that
> case, the diffusion of molecules will be presented, and it can be seen
> as a picture that the molecules are moving parallelly to the plane's
> substrate to find out the activate sites. And of course, the center of
> mass is not changed at all belong to Oz component.

yes, but the molecule cannot rotate if you fix the z components of all its  
atoms: it is a condition sufficient to fix the center of mass, but not  
necessary.

cheers



-- 
Lorenzo Paulatto

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