The Spectroscopy and Photophysical Behavior of Diphosphine- and Diisocyanide-Containing Coordination and Organometallic Oligomers and Polymers: Focus on Palladium and Platinum, Copper, Silver, and Gold

The field of organometallic and coordination oligomers and polymers has rapidly flourished in recent years [1–11]. The quest for finding new materials is driven by applications in photonics such as light-emitting-diodes, nonlinear optical and photoconducting materials and photovoltaic cells, electronic devices including materials based on semi-conductivity properties, liquid crystals useful in digital display, nanomaterials, and heterogeneous catalysis. Although the field is “dominated” by the use of N-containing and organometallic assembling ligands, relatively little is known about oligomers and polymers built on diphosphines and diisocyanides [2]. This chapter deals more particularly with recent advances in spectroscopy and photophysical behavior of coordination and organometallic polymers based on the diphosphine and diisocyanide bridging ligands involving direct P-M and NC-M bonds in the backbone, mainly for cases where the metals are palladium, platinum, cooper, silver, and gold. The photophysical parameters and phenomena addressed in this chapter are triplet energy extracted from the emission maxima, excited state lifetimes extracted from luminescence kinetics, emission quantum yields, emission quenching, photoinduced electron and energy transfers, and exciton phenomena. In addition, photovoltaic cell performance for one case is also addressed. Although this field appears to be in its infancy when compared with the well established organometallic and N-donor ligand-containing polymers, very clear advances are being reported at an ever-increasing pace. This chapter stresses the comparison between the polymers, oligomers, and the mononuclear related complexes in an attempt to show how the phophysical parameters and phenomena are influenced by the presence of interacting short-, medium-, and long-chains.