title: Microscopic theory of singlet exciton fission. III. Crystalline pentacene.
abstract: We extend our previous work on singlet exciton fission in isolated dimers to the case of crystalline materials, focusing on pentacene as a canonical and concrete example. We discuss the proper interpretation of the character of low-lying excited states of relevance to singlet fission. In particular, we consider a variety of metrics for measuring charge-transfer character, conclusively demonstrating significant charge-transfer character in the low-lying excited states. The impact of this electronic structure on the subsequent singlet fission dynamics is assessed by performing real-time master-equation calculations involving hundreds of quantum states. We make direct comparisons with experimental absorption spectra and singlet fission rates, finding good quantitative agreement in both cases, and we discuss the mechanistic distinctions that exist between small isolated aggregates and bulk systems.
authors.affiliation: Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.
authors.forename: Timothy C
authors.initials: TC
authors.lastname: Berkelbach
authors.affiliation: Center for Functional Nanomaterials, Brookhaven National Laboratory, Upton, New York 11973-5000, USA.
authors.forename: Mark S
authors.initials: MS
authors.lastname: Hybertsen
authors.affiliation: Department of Chemistry, Columbia University, 3000 Broadway, New York, New York 10027, USA.
authors.forename: David R
authors.initials: DR
authors.lastname: Reichman