Irreverent Nature of Dissymmetry Factor and Quantum Yield in Circularly Polarized Luminescence of Small Organic Molecules

Yuya Nagata; Tadashi Mori

doi:10.3389/fchem.2020.00448

Irreverent Nature of Dissymmetry Factor and Quantum Yield in Circularly Polarized Luminescence of Small Organic Molecules

Front Chem. 2020 Jun 9:8:448. doi: 10.3389/fchem.2020.00448. eCollection 2020.

Authors

Yuya Nagata¹, Tadashi Mori²

Affiliations

¹ Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Sapporo, Japan.
² Department of Applied Chemistry, Graduate School of Engineering, Osaka University, Osaka, Japan.

Abstract

Recently, a rational modification of small organic molecules has attracted considerable attention for designing advanced materials with enhanced circularly polarized luminescence (CPL) activity. A particular emphasis has been placed on fully allowed π-π^* transition of rigid aromatic systems, due to their relatively superior emission properties or quantum yields of luminescence (Φ_lum). However, their dissymmetry factors (g _lum), differential left and right CPL intensities, are typically disappointingly low at least in one to two orders of magnitude. Truly useful organic CPL materials, rated by a circular polarization luminosity index (Λ_CPL) per single molecule, possess both |g _lum| and Φ_lum values high. However, how to improve these two factors simultaneously with a proper molecular design is an open question. Here, we addressed this issue by theoretical and statistical inspection on a possible relation of the g _lum and Φ_lum values. According to the analysis, we propose simple, unpretentious, yet pertinent guidelines for designing superior organic CPL materials for the future with large Λ_CPL values.

Keywords: allowed π-π* transition; circularly polarized luminescence; dissymmetry factor; luminescence quantum yield; structure-chiroptical property relationship.

Publication types

Review