An investigation of Solid‐State Emission of Halogenated Diphenyl Phosphanyl Anthracenes.

In today's world, the development and research of optoelectronic materials and devices based on solid‐state luminescence is essential. Due to their versatile application possibilities, e.g. as light‐emitting diodes or lasers, they are already indispensable. This work presents three halogenated anthracene derivatives [9‐PPh2‐10‐X‐(C14H8)] and their respective photoluminescent behavior in solution and in the solid state. The formation of halogen–π interactions in the solid state leads to unanticipated luminescence properties for the chlorinated species, resulting in a strong bathochromic shift, green fluorescence and a longer lifetime. In contrast, the other two derivatives, which in turn form only weak π–π interactions due to a small overlap of the anthracene rings, barely change their luminescence behavior in the solid state. By employing additional charge density studies, the structure–property correlation is also investigated. In particular, focus is given to halogen bonding and halogen–π interactions and their influence on photophysical properties of the studied compounds. Through the new knowledge gained, this study will help in the future development and selective application of the photophysical properties of solid‐state luminescent materials. [ABSTRACT FROM AUTHOR]