Tungsten nitrosyl hydrides

First, we look at the term which is closely related to the term from the perturbational analysis. The trend predicted for the influence of the trans-ligand is reflected in the values. We also note that the orbital interaction energy for the tungsten nitrosyl hydride systems is essentially the same, independent of the number of phosphine ligands. For all three compounds, the steric contribution AP is stabilizing, and therefore dominated by attractive electrostatic interactions. Increasing the number of P-donors further increases the absolute value of A , and strengthens the TM-H bond. 

Group 6 Molybdenum and Tungsten Nitrosyl Hydrides for Ionic Hydrogenations 176... 

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