ncpchem

The CHFClBr equilibrium geometry, optimised at the .. level (taken from here), was scaled in the range 0.5 - 2.0 and the total and EPV energy was calculated at the B3LYP level. As pointed out by Peter the bond stretching will inevitably lead to a breakdown of the SCF model. Indeed one observes that the HOMO-LUMO gap closes and the SCF did not converge beyond scaling factor 1.4

Nuclear repulsion energy

Total energy

Total energy

Total EPV energy