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Updated: Feb 24, 2026
08:04
Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
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Excitonically Coupled States in Crystalline Coordination Networks
Ritesh Haldar1, Antoine Mazel2, Reetu Joseph3
1Karlsruhe Institute of Technology (KIT), Institute of Functional Interfaces (IFG), Hermann-von-Helmholtz Platz-1, 76344, Eggenstein-Leopoldshafen, Germany.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|August 18, 2017
Summary
Surface-mounted metal-organic frameworks (SURMOFs) incorporating core-substituted naphthalene diimides (cNDIs) exhibit unique photophysical properties. These supramolecular assemblies offer novel ways to control light interactions in advanced materials.
Area of Science:
- Materials Science
- Photophysics
- Supramolecular Chemistry
Background:
- Chromophore proximity drives excitonically coupled states via noncovalent interactions (π-π/CH-π).
- These coupled states alter photophysical properties, influenced by interaction strength and molecular orientation.
- Supramolecular assemblies allow controlled variation of these parameters for tailored optical properties.
Purpose of the Study:
- To investigate the photophysical properties of core-substituted naphthalene diimides (cNDIs) within surface-mounted metal-organic frameworks (SURMOFs).
- To compare the optical characteristics of cNDIs in SURMOFs with conventional aggregates.
- To explore the potential of SURMOFs for controlling photophysical properties through structural design.
Main Methods:
- Fabrication of MOF thin films on transparent substrates using cNDI-based organic linkers.
- Thorough characterization of the optical and structural properties of the highly ordered chromophoric assemblies.
- Investigation of excited-state properties and energy levels within the crystalline SURMOF structure.
Main Results:
- cNDIs incorporated into SURMOFs display optical properties distinct from solution or crystalline aggregates.
- The crystalline SURMOF material exhibits non-emissive excited states.
- Structural modifications provided insights into the coupling mechanisms responsible for the observed excited-state energy levels.
Conclusions:
- SURMOFs provide a platform for creating highly ordered chromophoric assemblies with tunable photophysical properties.
- The formation of non-emissive excited states in cNDI-based SURMOFs highlights the influence of supramolecular organization on excited-state dynamics.
- This work demonstrates the potential of rationally designed SURMOFs for advanced optoelectronic applications.
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