Visible Photoluminescence in Polysilanes

Summary.

 The photoluminescence spectrum of poly-(methyl-(phenyl)-silanediyl) shows a strong narrow peak in the UV region which is of excitonic nature and related to σ^*-σ transitions. The broad emission peak in the visible region is related to polymer branching, charge transfer transitions, and defect electronic states (backbone scission). Chemical substitution of the Si backbone with π-conjugated side groups allows to generate photoluminescence also in the visible region.