I ran NBO analysis on a set of ~ 100 small molecules (4 heavy atoms max), and compared the NBO analysis with HF and B3LYP (both using the 6-311+G* basis set).
In my results, I find that NBO hyperconjugation energies obtained from the NBO analysis with the DFT wavefunction/density are basically the same (but scaled down) as those obtained with the HF wavefunction given as input.
Is that a normal behaviour to observe? Shouldn’t the wavefunctoin/density matrix be rather different when comparing HF and B3LYP? Has anyone else noticed this in the past?