Abstract
Molecular vibrations play a critical role in the charge transport properties of weakly van der Waals bonded organic semiconductors. To understand which specific phonon modes contribute most strongly to the electron-phonon coupling and ensuing thermal energetic disorder in some of the most widely studied high-mobility molecular semiconductors, state-of-the-art quantum mechanical simulations of the vibrational modes and the ensuing electron-phonon coupling constants are combined with experimental measurements of the low-frequency vibrations using inelastic neutron scattering and terahertz time-domain spectroscopy. In this way, the long-axis sliding motion is identified as a "killer" phonon mode, which in some molecules contributes more than 80% to the total thermal disorder. Based on this insight, a way to rationalize mobility trends between different materials and derive important molecular design guidelines for new high-mobility molecular semiconductors is suggested.
Highlights
The last decade has witnessed drastic improvements of the electronic properties, environmental and operational stability and processibility of organic semiconductors (OSCs) [1,2]
We model the spectra by fully-periodic quantum mechanical calculations and use the obtained set of normal phonon modes and their frequencies to determine the vibrational amplitudes and the corresponding mode-resolved electron-phonon coupling constants
We focus our work on the classical high mobility OSCs, pentacene and rubrene, as well as a group of thienoacenes, which have emerged as a very promising class of high mobility molecules
Summary
The last decade has witnessed drastic improvements of the electronic properties, environmental and operational stability and processibility of organic semiconductors (OSCs) [1,2].
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
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 callDisclaimer: 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.
