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Updated: Jul 24, 2025
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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
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A Complex Reaction Network Model for Spontaneous Mirror Symmetry Breaking in Viedma Deracemizations
María E Noble-Terán1, José-Manuel Cruz2, Hugo I Cruz-Rosas1
1Centro de Investigaciones Químicas - IICBA, Universidad Autónoma del Estado de Morelos, Avenida Universidad 1001, 62209, Cuernavaca, Morelos, Mexico.
Summary
Viedma deracemization uses grinding to create pure crystals from mixtures. This study models the process, revealing specific grinding intensities and autocatalysis are key to spontaneous mirror symmetry breaking.
Area of Science:
- Crystallization science
- Chemical kinetics
- Chiral chemistry
Background:
- Viedma deracemization is a non-equilibrium method for obtaining enantiomerically pure crystals from racemic mixtures.
- The underlying mechanisms of attrition-enhanced chiral symmetry breaking remain incompletely understood.
Purpose of the Study:
- To develop and validate a comprehensive kinetic model for Viedma deracemization.
- To elucidate the fundamental principles governing spontaneous mirror symmetry breaking (SMSB) in this process.
Main Methods:
- Development of a continuous kinetic rate equation model incorporating primary nucleation, crystal growth, and Ostwald ripening.
- Implementation of a microreversible kinetic scheme with size-dependent solubility (Gibbs-Thomson rule).
- Validation using experimental data from a sodium chlorate (NaClO3) deracemization experiment.
Main Results:
- The model successfully reproduces spontaneous mirror symmetry breaking (SMSB) under simulated grinding conditions.
- Identification of a bifurcation scenario defining critical grinding intensity limits for deracemization.
- Discovery that SMSB arises from multiple instances of concealed high-order autocatalysis.
Conclusions:
- The developed model provides new mechanistic insights into attrition-enhanced deracemization.
- Findings highlight the critical role of grinding intensity and autocatalysis in achieving enantiomeric purity.
- The study offers a framework for understanding chiral molecule synthesis and biological homochirality.
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