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Line Shape Analysis of Dynamic NMR Spectra for Characterizing Coordination Sphere Rearrangements at a Chiral Rhenium Polyhydride Complex
Published on: July 27, 2022
Highly emitting concomitant polymorphic crystals of a dinuclear rhenium complex
Elsa Quartapelle Procopio1, Matteo Mauro, Monica Panigati
1Dipartimento di Chimica Inorganica Metallorganica e Analitica Lamberto Malatesta, Università degli Studi di Milano, via Venezian 21, I-20133 Milano, Italy.
Journal of the American Chemical Society
|September 28, 2010
Summary
This study reveals two solid-state polymorphs of a dinuclear rhenium complex, exhibiting distinct photoluminescence properties. These polymorphs undergo a reversible phase transition, highlighting the impact of crystal organization on photophysical behavior.
Area of Science:
- Inorganic Chemistry
- Solid-State Chemistry
- Photochemistry
Background:
- Dinuclear rhenium complexes can exhibit polymorphism.
- Solid-state packing influences molecular properties.
- Photoluminescence is sensitive to molecular environment.
Purpose of the Study:
- To investigate the solid-state properties of a dinuclear rhenium complex.
- To understand the relationship between crystal structure and photoluminescence.
- To explore phase transitions in crystalline materials.
Main Methods:
- Crystallization to obtain distinct polymorphs (1Y and 1O).
- Photoluminescence spectroscopy to measure quantum yields and emission spectra.
- Variable temperature X-ray diffraction to study phase transitions.
Main Results:
- Two polymorphs (1Y and 1O) were obtained with different crystallization rates.
- Both polymorphs showed significantly enhanced photoluminescence in the solid state compared to solution.
- A single-crystal-to-single-crystal phase transition (1O → 1Y) was observed at 443 K.
- Polymorphs displayed different absorption and emission maxima despite weak intermolecular interactions.
Conclusions:
- The local organization of molecular dipoles in the crystal significantly impacts photophysical properties.
- Polymorphism in dinuclear rhenium complexes can lead to distinct optical behaviors.
- Crystal engineering strategies can tune the photoluminescence of metal complexes.
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