USE OF THE EXPERIMENTAL ELECTROSTATIC POTENTIAL TO PREDICT THE COMPLEXATION OF METALLIC ATOMS - THE CASE OF BIPYRIMIDINE LIGANDS

The electron density distribution of 2,2'-dimethyl-6,6'-diphenyl-4,4'- bipyrimidine was determined from high-resolution low-temperature X-ray diffraction data. The electron density multipolar parameters were use d to calculate the electrostatic potential around a molecule removed f rom the crystal lattice. As expected, electronegative regions were fou nd at the vicinity of nitrogen atoms which are expected to participate in a metal complexation. It is confirmed by mapping out the electrost atic potential of the molecule in its model s-cis conformation.