The synthesis and a detailed investigation into the electronic properties of mononuclear and dinuclear Ru (II) complexes of the ligand bis (2-hydroxyphenyl)-2, 5-dihydropyrazine (H2BHD) is described. In these complexes the Ru (II) moieties are bound through O, N coordination to an anionic phenolate and the pyrazine bridge. Relatively few reports are available on the dinuclear complexes bridged across a phenolate and this study provides ...