whats is the difference between using pxx, pyy, pzz, etc and stress/atom command

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1

Hello all,

I saw in the codes that for calculationg the stress in order to get
stress/strain results, they use the components of pressure which are
pxx, pyy, .... as the stresses.
is it right??
Shouldn't we use stress/atom command?
The results in two cases are really different.

2

Hello all,

I saw in the codes that for calculationg the stress in order to get
stress/strain results, they use the components of pressure which are
pxx, pyy, … as the stresses.
is it right??
Shouldn’t we use stress/atom command?

Depends. Computing the global pressure/stress is much more efficient. If you can use it, the you should do it.

The results in two cases are really different.

Virial stress and pressure are not the same.

Axel

3

In particular note the volume term missing from stress/atom. This

is discussed in detail on the compute stress/atom doc page.

Steve