Title: Charge transport network dynamics in molecular aggregates

Abstract

Due to the nonperiodic nature of charge transport in disordered systems, generating insight into static charge transport networks, as well as analyzing the network dynamics, can be challenging. Here, we apply time-dependent network analysis to scrutinize the charge transport networks of two representative molecular semiconductors: a rigid n-type molecule, perylenediimide, and a flexible p-type molecule, $bBDT{\left(TDPP\right)}_2$ . Simulations reveal the relevant timescale for local transfer integral decorrelation to be $\mathrm{\sim }$ 100 fs, which is shown to be faster than that of a crystalline morphology of the same molecule. Using a simple graph metric, global network changes are observed over timescales competitive with charge carrier lifetimes. These insights demonstrate that static charge transport networks are qualitatively inadequate, whereas average networks often overestimate network connectivity. Finally, a simple methodology for tracking dynamic charge transport properties is proposed.

Authors:

Jackson, Nicholas E.; Chen, Lin X.; Ratner, Mark A.

Publication Date:

2016-07-20

Research Org.:

Energy Frontier Research Centers (EFRC) (United States). Argonne-Northwestern Solar Energy Research Center (ANSER)

Sponsoring Org.:

USDOE Office of Science (SC), Basic Energy Sciences (BES)

OSTI Identifier:

1267525

Alternate Identifier(s):

OSTI ID: 1388188

Grant/Contract Number:  

DC-SC0001059; SC0001059

Resource Type:

Journal Article: Published Article

Journal Name:

Proceedings of the National Academy of Sciences of the United States of America

Additional Journal Information:

Journal Name: Proceedings of the National Academy of Sciences of the United States of America Journal Volume: 113 Journal Issue: 31; Journal ID: ISSN 0027-8424

Publisher:

Proceedings of the National Academy of Sciences

Country of Publication:

United States

Language:

English

Subject:

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; catalysis (homogeneous); catalysis (heterogeneous); solar (photovoltaic); solar (fuels); photosynthesis (natural and artificial); bio-inspired; hydrogen and fuel cells; electrodes - solar; defects; charge transport; spin dynamics; membrane; materials and chemistry by design; optics; synthesis (novel materials); synthesis (self-assembly)