This article from the Journal of Chemical Physics termed Up- and Down-Conversion in Molecules and Materials aims to bring together the different ways to convert energy in materials, highlight the common concepts, and define the most promising directions and challenges for future research. Downconversion (DC) describes the conversion of higher-energy particles into single or multiple lower-energy particles. The article highlights examples of singlet fission and lanthanide-based DC systems. Many of the contributions to this article collection focus on singlet fission (SF). The article also shows that in molecules, the particles that carry energy are excitons, and the conversion of exciton energy between a spin-singlet exciton and two spin-triplet excitons can be used for upconversion (UC) or DC. Molecular DC is termed singlet fission (SF), where one singlet exciton is converted into two triplet excitons,1 and molecular UC is termed triplet fusion or triplet–triplet annihilation (TTA), where two spin-triplet excitons combine to form a singlet exciton.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)
- Physical and Theoretical Chemistry