Possible to calculate stress?

[su rui]

I am not very clear how the analytical forces are calculated in AMP. For my work, I need to calculate stress to evaluate the stress strain curves. Is it possible to evaluate the stresses analytically or we should rely on the numerical stresses in ASE?

[Alireza Khorshidi]

Unfortunately we do not have get_stress method implemented yet. A few ASE calculators have this method, among them Jacapo (Dacapo) and Castep. You may want to check their source code and make sure how they calculate the stress, but as a first guess, I think they return the viral definition as the stress tensor. The viral stress should be pretty much straightforward to implement as long as we have atomic forces accessible. You may even want to push your implementation to the amp code in a separate branch.

[andrew_peterson]

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[andrew_peterson]

Issue #189 was marked as a duplicate of this issue.