The π-interactions of ammonia ligands evaluated byab initioligand field theory

Abstract

Ammonia and amine ligands are commonly assumed to be σ-only ligands in coordination chemistry, i.e. they are not expected to interact significantly with a metal via a π-path. Ligand field...

AOMadillo: A program for fitting angular overlap model parameters

“…There are many examples for which the combination of LFT, AOM and computational chemistry work in a clear and unambiguous way. As we showed in previous publications, 21,25…”

“…With the above examples and the ones in previous publications 21,25 it is shown that our procedure can be applied to a variety of transition metal complexes. Nonetheless, the user must be careful and aware of problems and ambiguities in the AOM parameterization choices that might not be obvious.…”

“…Even for ligands that had been considered σ-only so far, we expect a significant π-interaction. 25 The two π-interactions e πx and e πy can be discerned, which increases the parameter space. The additional angle that needs to be defined can be either provided by the user or calculated from the structure of the molecule.…”

“…An example with distorted bond angles is shown in Table 1. We have shown previously that this approach works and allows to fit AOM parameters to formerly underdetermined problems such as tetrahedral 21 and octahedral 25 complexes.…”

“…4 2þ , which can be considered an archetypal example of d-s mixing 25. ‡ If optimized freely, the SCN À ligands orient themselves to the hydrogen atoms and a Cu-SCN-H-N-Cu pseudo-cycle forms.…”