Fig. 4: Factors affecting through-space conjugation (TSC) and CL process.
From: Emergent clusteroluminescence from nonemissive molecules
a Dihedral angles between the phenyl rings (θ1 and θ2) in the oligo(phenylene methylene) (OPM[n], n = 3, 4) chain. The diphenylmethane (DPM) unit with appropriate dihedral angle favorites intramolecular (π,π) TSC leads to a red-shift in emission color and an increase in quantum yield (ΦPL). b The CL behaviors and electrostatic potential maps of triphenylmethane (TPM) and its derivatives carrying electron-donating (TPM-NMe) and electron-withdrawing (TPM-NO2) substituents (isovalue = 0.02, GaussView). c The CL behaviors, LUMO diagrams (isovalue = 0.05, IQmol), and intramolecular interactions of DPM and its derivatives containing heteroatoms; the modes of TSC [(π,π), (n,π), (σ,π), (n,n)] are increased with increasing the number of nitrogen atoms in the DPM derivatives. d The extent of charge separation (isovalue = 0.05, IQmol) and solvatochromic effect in the luminogens involving TBCT and TSCT processes: the emission color of the CLgen with complete charge separation (DMA-CN-DPM) bathochromically shifts to a larger extent with an increase in the solvent polarity (1 = hexane, 2 = toluene, 3 = tetrahydrofuran, 4 = chloroform, 5 = acetone, 6 = dimethylformamide, 7 = dimethyl sulfoxide, 8 = acetonitrile); concentration is 5 × 10-4 M. b is adapted with permission from ref. 65 Copyright (2021) American Chemical Society. c is adapted with permission from ref. 41 Copyright (2025) Cell Press. d is adapted with permission from ref. 40 Copyright (2024) Springer Nature.
