Do bonding and anti-bonding orbitals exist for ionic bonds?
Bonding and antibonding orbitals in a homonuclear diatomic molecule  A-B should mix due to polarization to give rise to pair of atomic orbitals with delocalized tails  for an ionic heteronuclear diatomic molecule. Now suppose A more electronegative and is the rightful anion and B the cation. The tailed atomic orbital of A is the bonding orbital(ie. A:- B°+) and the one belonging to B is the antibonding (ie. A°+ B:-). See original paper on Coulson Fischer theory.