2,2’-Biphospholes:New Building Blocks For Tuning The HOMO-LUMO Gap

Organic p-conjugated systems are useful lightweight semi-conducting materials for electronics.The control of their HOMO-LUMO energy gap is one of the key issues in the optimization of these materials.There are several structural factors in controling of the energy gap. Among all these structural factors, only the torsion angle is considered to be the most effective potential regulator. Herein, we show that exploiting the properties of the2,2’-biphosphole unit allows a unique combined covalent/metal coordination approach for an on-demand tuning of the torsion angle between the two conjugated P heteroles. At the same time, a perfect white emission has been obtained with a phosphole-based dopant. The fact that this novel series of P-basedunits within π-conjugated systems can be employed as materials in optoelectronics opens interesting perspectives towards the development of novel materials.