HI All

I imported the structure of GaN using “read data” with N-total number of atoms divided in two types. Then I assigned the atoms as Type-1 (Ga) and Type-2 (N) so that I can use SW potential. My problem comes when I want to calculate the VACF (velocity auto correlation function ) of specific atoms not of all (say VACF of Ga or N at the center or at the surface)…So I was wondering if there is a trick to do this.

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Thanks,

Z.

HI All

I imported the structure of GaN using "read data" with N-total number of

atoms divided in two types. Then I assigned the atoms as Type-1 (Ga) and

Type-2 (N) so that I can use SW potential. My problem comes when I want to

calculate the VACF (velocity auto correlation function ) of specific atoms

not of all (say VACF of Ga or N at the center or at the surface).....So I

was wondering if there is a trick to do this.

you can define groups by region as well, but please see the very

recent discussion in this forum on the fundamental ambiguity problem

with such an approach (i.e. you cannot use a dynamic group) in the

context of computing the MSD. it is the same problem here.