Structural Dynamic Impact of Chromophores on Singlet Fission

Singlet fission (SF) represents a unique mechanism that allows a single high-energy photon to split into two triplet excitons, significantly enhancing the quantum efficiency of photovoltaic and optoelectronic materials. Therefore, SF shows great potential for applications in solar cells and optoelectronic devices. Despite significant progress in recent years, synergistic effects of various factors that govern the structural dynamics of solvated chromophores individually or jointly and lead to the complicated dynamics of SF still require further exploration. This Perspective systematically analyzes various factors that affect and even modulate the efficiency and mechanism of SF, especially the structural dynamics of solvated chromophores, including molecular vibrations, chromophore dynamic interactions, solvent and environmental fluctuations, temperature and thermodynamic variations, and pressure and physical changes. The inherent dynamic characteristics of these factors dominate the structural and electronic properties and interchromophore interactions, thereby manipulating the energetics and kinetic pathways of SF and ultimately determining the SF efficiency and feasibility. The discussions presented in this Perspective provide dynamics insights, important foundations, and strategies for future design of materials and performance optimization of optoelectronic devices through considering dynamic factors.