CLF v. AOM: We win!
After over 30 years of scratching away at the problem, the issue of whether the potential-based CLF approach gives a better picture of ligand field theory (LFT) than the orbital-overlap-based AOM has finally been settled. Using state-of-the-art CASSCF/NEVPT2 wavefunction theory as implemented in the ab initio LFT scheme in the ORCA program system, it can categorically be demonstrated that the Gerlochian view of LFT - i.e. the CLF model - is closer to reality than the AOM. The first installment is due out in EJIC mid April, 2020. (DOI: 10.1002/ejic.202000143)