Singlet fission in spiroconjugated dimers

Area of Science:

• Photophysics and photochemistry
• Organic electronics
• Computational chemistry

Background:

• Singlet fission (SF) is a key process for efficient solar energy conversion.
• Controlling electronic interactions between chromophores is crucial for SF viability.
• Spiroconjugation offers a unique method for linking chromophores and tuning their electronic properties.

Purpose of the Study:

• To computationally investigate intramolecular singlet fission in spiroconjugated dimers.
• To characterize excited electronic states and interstate couplings.
• To explore the role of vibrational modes in the singlet fission mechanism.

Main Methods:

• Computational modeling of spiroconjugated dimers.
• Characterization of low-lying excited electronic states.
• Evaluation of interstate couplings and singlet fission mechanisms.
• Analysis of vibrational mode contributions to exciton fission.

Main Results:

• Spiro linkage facilitates favorable excited singlet and triplet energies.
• Low-lying charge resonance states are identified as crucial for triplet pair formation.
• The spiro architecture supports efficient singlet fission pathways.

Conclusions:

• Spiroconjugated dimers are promising candidates for efficient singlet fission.
• The spiro linkage provides a versatile platform for designing SF materials.
• This work provides insights into designing molecules for enhanced solar energy applications.