Abstract

Singlet fission (SF) is a spin-allowed process in which a singlet exciton, 1(S1S0), within an assembly of two or more chromophores spontaneously down-converts into two triplet excitons via a multiexciton correlated triplet pair state, 1(T1T1). To elucidate the involvement of charge transfer (CT) states and vibronic coupling in SF, we performed 2D electronic spectroscopy (2DES) on dilute solutions of a covalently linked, slip-stacked terrylene-3,4:11,12-bis(dicarboximide) (TDI) dimer. This dimer undergoes efficient SF in nonpolar 1,4-dioxane and symmetry-breaking charge separation in polar dichloromethane. The various 2DES spectral features in 1,4-dioxane show different pump wavelength dependencies, supporting the presence of mixed states with variable 1(S1S0), 1(T1T1) and CT contributions that evolve with time. Analysis of the 2DES spectra in dichloromethane reveals the presence of a state having largely 1(T1T1) character during charge separation. Therefore, the 1(T1T1) multiexciton state plays an important role in the photophysics of this TDI dimer irrespective of solvent polarity.

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.