Singlet fission (SF) hold immense potential in efficient solar energy conversion on account of the vital role in alleviation of thermalization loss for high-energy photons. Although tremendous effort and progress have been made, the application of such a potential process in practical photovoltaic devices remains a formidable task. Therefore, exploitation of efficient SF molecular systems and in-depth study of their excitonic dynamics are of great importance to the implementation of photovoltaic application. Herein, we have developed a series of benzodipyrrolidone (BDPP) derivatives and delved into the SF dynamics in these loose packing thin films using time-resolved spectroscopy and morphology analyses. Results illustrate that efficient triplet formation could be achieved in all these loose packing thin films with a distinct crystallographic form and intermolecular packing mode. Suitable excited state energy levels, strong absorption in the blue–green light region, and excellent stability render BDPP as a robust SF molecular system targeted to practical utilization.
