Hi PSi4 community,
I remember that PSI4 provides a module to quantify self interaction error, called orbital many-electron self-interaction error, and actually used for my publication.
But that feature is missing in the current version?
I couldn’t find this in the current manual.
I’m not aware of any self-interaction quantification in Psi. We have some tools that can help analyze this, but I’m not familiar with their use.
There is no one way to quantify self-interaction error for a general computation. If you can describe what the self-interaction quantification procedure was, I can look again to see if I can find anything, but I’m doubtful.
Some methods exist for quantifying and removing self-interaction error in the literature, but they tend to be very costly and also have very bad side effects, see our paper https://pubs.acs.org/doi/10.1021/acs.jctc.6b00347.
Usually the best one can do is look at functionals with a varying amount of exact exchange to see how your property changes. If it is very sensitive to the presence of exact exchange, self-interaction error may play a significant role.