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Updated: Apr 1, 2026

Atomic Scale Structural Studies of Macromolecular Assemblies by Solid-state Nuclear Magnetic Resonance Spectroscopy
Published on: September 17, 2017
The HOMO Nodal Arrangement in Polychromophoric Molecules and Assemblies Controls the Interchromophoric Electronic
Marat R Talipov1, Tushar S Navale1, Rajendra Rathore2
1Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, WI 53201-1881 (USA).
Abstract:
Triptycenes spontaneously assemble into two-dimensional networks in which long-range charge transport is facilitated by the extensive electronic coupling through the triptycene framework (intramolecularly) and by cofacial π-stacking (intermolecularly). While designing and synthesizing next-generation triptycenes containing polyaromatic chromophores, the electronic coupling amongst the chromophores was observed to be highly dependent on the nature and position of the substituents. Herein, we demonstrate using hexaalkoxytriptycenes that the electronic coupling amongst the chromophores is switched on and off by a simple repositioning of the substituents, which alters the nodal arrangement of the HOMOs of the individual chromophores. A visual inspection of the HOMOs can thus provide a ready evaluation of the electronic coupling in polychromophoric molecules/assemblies, and will serve as an important tool for the rational design of modern charge-transport materials.
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