This PR completes #1900 although the final product is to introduce "phantom" rather than "artificial" atoms.
Briefy, a phantom atom is a normal SpeciesAtom and is part of a Species, connected to other SpeciesAtoms, and is evolved by MC / MD in the standard way. However, it makes no contribution to correlation functions or weights as calculated by the various correlation modules. Thus, they can affect the behaviour of a species / system but are invisible to structural probes.
Closes #1900.
Follow-on issue #1952 captures further work.
This PR completes #1900 although the final product is to introduce "phantom" rather than "artificial" atoms.
Briefy, a phantom atom is a normal
SpeciesAtomand is part of aSpecies, connected to otherSpeciesAtoms, and is evolved by MC / MD in the standard way. However, it makes no contribution to correlation functions or weights as calculated by the various correlation modules. Thus, they can affect the behaviour of a species / system but are invisible to structural probes.Closes #1900. Follow-on issue #1952 captures further work.