Recent advances in oligomers/polymers with unconventional chromophores

Nonconventional chromophores, without classic conjugation and rigid units, are a hot topic of luminescent materials nowadays because of their unique under-explored fundamental properties and their promising applications. Despite the increased attention recently paid to this exciting area, the structural design and the mechanism of photoluminescence in these materials remain unclear and controversial. Different luminescence mechanisms have been successively proposed in recent years, such as oxidation, aggregation of carbonyl units, interactions with phenyl groups, clustering of chromophores and through-space conjugation, etc. This review summarizes oligomers/polymers with unconventional chromophores reported in recent years, which are classified according to their chemical structures and luminescence mechanisms. We present an interconnected overview of the topic highlighting the opportunities for new materials synthesis, looking forward to accelerated future innovation and developments in this area.