Electronic wavefuntions must be constructed to have permutational antisymmetry because the N electrons are indistinguishable Fermions 9.1: Electronic Configurations Atoms, linear molecules, and non-linear molecules have orbitals which can be labeled either according to the symmetry appropriate for that isolated species or for the species in an environment which produces lower symmetry. 9.2: Antisymmetric Wavefunctions A general introduction to the anti-symmetric nature of multi-electron wavefunctions (as fermions) and the consequence this has on construction and application of these wavefunctions.