Ligand, classification

The catalytic efficiency is also often determined by the nature of the coordinating ligands. The electronic and steric nature of the ligand has a remarkable influence on the activity of the catalytic systems and many attempts have been made to obtain a comprehensive system of ligand classification that allows correlation of catalytic activity and ligand structure. In this section it will be shown how homogeneous catalysts for CO2 transforming reactions can be developed and optimized on the basis of these concepts by combination of experimental and theoretical work. 

Figure 21 Simple examples of ligand classifications when exhibiting their maximum coordination modes.

Ma SL, Joung JY, Lee S, Cho KH, No KT (2012) PXR ligand classification model with SPED weighted WHIM and CoMMA descriptors. SAR QSAR Environ Res 23(5-6) 485-504 http //rdkit.org/docs/api/rdkit.Chem.MACCSkeys-pysrc.html... 

By the first ligand classification system that includes charges, the total number of valence electrons is then equal to the number of d-electrons plus the total number of electrons donated by both neutral and charged ligands. 

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