Phthalocyanoruthenium complexes and polymers with bridged ligands

Abstract

Electronic properties related to the semiconductivity of monomers and polymers of phthalocyanoruthenium with bidentate bridging ligands, [PcRu(L2)] and [PcRu(L)]n, have been investigated from density functional calculations (L = pyrazine, triazine, tetrazine, 4,4′-bipyridine, and bipyridyacetylene). The Pauli repulsion is the origin that the bridging axial ligands (L) prefer be located towards the aza positions of the macrocycle. The intrinsic semiconducting properties depend on the frontier band. The valence band is composed largely by the ruthenium dxy orbital. The conduction band is composed for a mixture between the metallomacrocycle and bridged ligand orbitals for systems formed by pyrazine, bipyridine, and bipyridyacetylene. However, this composition is different when the ligands are triazine and tetrazine, which they show a band composed by π* orbitals. © 2002 Elsevier Science B.V. All rights reserved.