B3LYP calculations limitations

Other DFT-B3LYP calculations were performed by Siegbahn and coworkers [343], this time on a neutral model system L3CU. .. Cu L3 to probe the mechanism of tyrosinase action. The ligands L chosen to model histidines, were either ammonia or formimine. The authors focus on the choice of chemical model and its limitations, the location of the transition state for 0-0 activation... 

Our B3LYP/6-311+G calculations supported a limiting associative exchange mechanism on the aquated lithium cation as shown in Fig. 6 (90). 

The energetically favorable conformations of model alkyl nitronate (88) and related compounds (89 to 91) (283) were determined by the B3LYP/6-31G(d) method (see Chart 3.9). It appeared that the marked conformations with the minimized dipole moments are energetically most favorable for compounds (88-91) (the use of the dipole-dipole interaction model in conformational analysis was also described in the publication (284)). Calculations including n-n interactions (see Fig. 3.1) did not change this situation because the contribution of this effect is equal in magnitude for both limiting conformations shown in Chart 3.9. 

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