English
 
User Manual Privacy Policy Disclaimer Contact us
  Advanced SearchBrowse

Item

ITEM ACTIONSEXPORT

Released

Paper

Nuclear dynamics of singlet exciton fission: a direct observation in pentacene single crystals

MPS-Authors
/persons/resource/persons21421

Rossi,  M.
Fritz-Haber-Institut der Max-Planck-Gesellschaft;
Simulations from Ab Initio Approaches, Theory Department, Max Planck Institute for the Structure and Dynamics of Matter, Max Planck Society;

/persons/resource/persons202770

Schwoerer,  H.
Miller Group, Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, Max Planck Society;

External Ressource
Fulltext (public)

2011.12016.pdf
(Preprint), 6MB

Supplementary Material (public)
There is no public supplementary material available
Citation

Seiler, H., Krynski, M., Zahn, D., Hammer, S., Windsor, Y. W., Vasileiadis, T., et al. (2020). Nuclear dynamics of singlet exciton fission: a direct observation in pentacene single crystals.


Cite as: http://hdl.handle.net/21.11116/0000-0007-751A-9
Abstract
Singlet exciton fission (SEF) is a key process in the development of efficient opto-electronic devices. An aspect that is rarely probed directly, and yet has a tremendous impact on SEF properties, is the nuclear structure and dynamics involved in this process. Here we directly observe the nuclear dynamics accompanying the SEF process in single crystal pentacene using femtosecond electron diffraction. The data reveal coherent atomic motions at 1 THz, incoherent motions, and an anisotropic lattice distortion representing the polaronic character of the triplet excitons. Combining molecular dynamics simulations, time-dependent density functional theory and experimental structure factor analysis, the coherent motions are identified as collective sliding motions of the pentacene molecules along their long axis. Such motions modify the excitonic coupling between adjacent molecules. Our findings reveal that long-range motions play a decisive part in the disintegration of the electronically correlated triplet pairs, and shed light on why SEF occurs on ultrafast timescales.