Boron chemistry lights the way: optical properties of molecular and polymeric systems.

Electrooptical and electronic materials are the subject of much research interest, whereby the focus has often been on electron-rich organic molecules. In the past years, new routes to electron-deficient systems have been developed that take advantage of the fact that three-coordinate boron is isoelectronic and isostructural with a positively charged carbocation, which allows neutral, p-type materials to be synthesized directly. This minireview summarizes recent work on compounds with 3- and 4-coordinate boron as well as boron clusters, placing it in the context of prior studies by the research groups of Williams and Glowgowski, Kaim, Lequan, and Marder.