Organic semiconductors (OSCs) have been of considerable interest for their potential applications in modern electronics, such as flexible displays and solar cells. Such materials are readily synthesized from solution, resulting in low-cost production with high synthetic yields. An important metric by which an optoelectronic material can be evaluated is the charge carrier mobility - the efficiency of moving a charged particle throughout a material before its annihilation. Charge carrier mobility values in OSCs are highly variable, with rubrene demonstrating mobility values as great as 40 cm2 V-1 s-1, while TIPS-Pentacene displays single digit mobility values. Understanding the distinct molecular properties that influence the charge carrier mobility is pivotal for the development of effective OSCs. While many factors influence carrier mobilities, scattering of carriers via electron-phonon coupling is one of the most detrimental to experimentally measured mobilities. Terahertz time-domain spectroscopy (THz-TDS) is a powerful technique in the evaluation of these materials, as the vibrations contributing to detrimental electron-phonon couplings are directly experimentally probed. In the case of OSCs, ‘killer-modes’ exist as specific terahertz vibrations that directly and strongly hinder the semiconducting ability of these materials by effectively reducing the overlap of the frontier orbitals involved in the charge transport process. The specific descriptions of these vibrational modes rely upon highly-accurate solid-state density functional theory (ss-DFT), which in turn provides the theoretical model by which the detrimental effects of these vibrations are evaluated. In this work we not only identify these ‘killer-modes’, but armed with this understanding, describe a rational design of derivatives which minimize the effect of terahertz vibrations upon charge transport.

Identification and characterization of ‘killer-modes’ in organic semiconductors with terahertz spectroscopy

Macromolecular Chemistry: The Second Century

[Author Benefits](https://scimeetings.acs.org/?utm_source=pubs_content_marketing&utm_medium=website&utm_campaign=0320_MCF_NPI_Launch_Spring_Homepage&ref=pubs_content_marketing)

[How to use SciMeetings](https://storage.googleapis.com/dl.morressier.com/acs/SciMeetings-ACSSpring2020-HowToGuide_M3020-Final.pdf)

[Frequently Asked Questions](https://storage.googleapis.com/dl.morressier.com/acs/SciMtng_ACSNMSp2020_FAQ_M3120_Final.pdf)

ACS Spring 2020 National Meeting & Expo

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.