Hi colleagues,
- Please see the detailed question there. So, some selection is important: either to keep existing ESPResSo-specific rotational formalism (does maybe someone could kindly provide a reference?) or to adjust the formulae implemented in ESPResSo. Even without a proper original reference: I'm personally OK to use existing ESPResSo formalism in the theoretical part of next papers just for the sake of consistency. But some clarity is important :-) Also, I'm ready to help with the adjustments by the PR.
P.S. As I mentioned in the issue: the discrepancy, probably, is very simple: some formalisms imply zero-th quaternion component as the real one and remaining as imaginary and some use the very last component. It sounds simple, but in a case of linear algebra operations and formulae compare: this is really sophisticated-to-handle difference.
Sincerely yours / mit freundlichen Grüßen,
Bogdan Tanygin