Orbital Interaction versus Electron Density of Phosphoryl Oxygen:
The organophosphorus compounds, namely trialkyl phosphates, phosphonates, phosphinates, and phosphine oxides, have been extensively used for complexing actinides. Hitherto, the assumption was that the enhanced electron density of phosphoryl oxygen (conventionally understood as the basicity of phosphoryl oxygen) in trialkyl phosphine oxides, when compared to phosphinates, phosphonates, and trialkyl phosphates, was primarily responsible for their better complexing behavior with actinides. However, for the first time, in the present study, we have demonstrated through quantum chemical calculations that "dispersion and orbital interactions" and not "phosphoryl oxygen electron density", are primarily responsible for the better complexing ability of phosphine oxides over other molecules.
Read More: J. Comput. Chem. 2023