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Updated: May 20, 2025
Hyperspectral Imaging as a Tool to Study Optical Anisotropy in Lanthanide-Based Molecular Single Crystals
Published on: April 14, 2020
Circularly Polarized Luminescence From Spontaneous Symmetry Breaking in a Bimetallic Eu-Al Complex
Marcin Górecki1, Elisa Gallo2, Luca Bellucci2
1Institute of Organic Chemistry, Polish Academy of Sciences, ul. Kasprzaka 44/52, Warsaw, Poland.
Abstract:
The emergence of optically active functional compounds through spontaneous chiral symmetry breaking is a rare but intriguing phenomenon with relevance of both practical and fundamental interest. Here we show that a racemic Eu-Al compound, bearing only non-chiral ligands, forms a conglomerate upon crystallization. Single crystals of the compound are electronic circular dichroism (ECD) and circularly polarized luminescence (CPL) active. Moreover, we found that a significant enantiomeric excess (50%) of either enantiomer is present in each crystallization batch (non-racemic conglomerate). Such spontaneous symmetry breaking leads not only to optically active single enantiomorph crystals but to an overall solid bulk with significant ECD and CPL.
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