Recently, I came across some lecture notes on electronic structure theory which had something peculiar about it. I noticed that FCI (configuration interaction) was introduced before Hartree-Fock theory, that got me thinking if its possible to think about FCI as an approach independent of HF theory as starting point (not particularly as post-HF method).
Would such an approach be possible?
In general can there be a generalized formalism for Full configuration interaction? (say in the form of a particle-hole construction, for example see the introduction section in arXiv:1906.11361)