Heterotrimetallic Mixed-Valent Molecular Precursors Containing Periodic Table Neighbors: Assignment of Metal Positions and Oxidation States.

A known trinuclear structure was used to design the heterobimetallic mixed-valent, mixed-ligand molecule [Co (hfac) -Na-Co (acac) ] (1). This was used as a template structure to develop heterotrimetallic molecules [Co (hfac) -Na-Fe (acac) ] (2) and [Ni (hfac) -Na-Co (acac) ] (3) via isovalent site-specific substitution at either of the cobalt positions. Diffraction methods, synchrotron resonant diffraction, and multiple-wavelength anomalous diffraction were applied beyond simple structural investigation to provide an unambiguous assignment of the positions and oxidation states for the periodic table neighbors in the heterometallic assemblies.