Reassessing the use of one-electron energetics in the design and characterization of organic photovoltaics

Brett M. Savoie, Nicholas E. Jackson, Tobin J. Marks, Mark A. Ratner

Research output: Contribution to journalArticlepeer-review

52 Citations (Scopus)


We present results showing that common approximations employed in the design and characterization of organic photovoltaic (OPV) materials can lead to significant errors in widely adopted design rules. First, we assess the validity of the common practice of using HOMO and LUMO energies in place of formal redox potentials to characterize organic semiconductors. We trace the formal justification for this practice and survey its limits in a way that should be useful for those entering the field. We find that while the HOMO and LUMO energies represent useful descriptive approximations, they are too quantitatively inaccurate for predictive material design. Second, we show that the excitonic nature of common organic semiconductors makes it paramount to distinguish between the optical and electronic bandgaps for materials design. Our analysis shows that the usefulness of the "LUMO-LUMO Offset" as a design parameter for exciton dissociation is directly tied to the accuracy of the one-electron approximation. In particular, our results suggest that the use of the "LUMO-LUMO Offset" as a measure of the driving force for exciton dissociation leads to a systematic overestimation that should be cautiously avoided.

Original languageEnglish
Pages (from-to)4538-4547
Number of pages10
JournalPhysical Chemistry Chemical Physics
Issue number13
Publication statusPublished - Apr 7 2013

ASJC Scopus subject areas

  • Physics and Astronomy(all)
  • Physical and Theoretical Chemistry

Fingerprint Dive into the research topics of 'Reassessing the use of one-electron energetics in the design and characterization of organic photovoltaics'. Together they form a unique fingerprint.

Cite this