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Updated: Jan 12, 2026
08:51
Coulomb Explosion Imaging as a Tool to Distinguish Between Stereoisomers
Published on: August 18, 2017
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Deconstructing Chirality: Probing Local and Nonlocal Effects in Azobenzene Derivatives with X-ray Circular Dichroism
Ajay Khanna1, Victor M Freixas2, Lei Xu3
1Theoretical Division, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, United States.
The Journal of Physical Chemistry Letters
|October 30, 2025
Summary
This study introduces site-specific X-ray circular dichroism (XCD) to resolve molecular chirality. XCD successfully distinguishes local and global chiral features, enabling precise control over chiroptical signals for designing advanced chiral systems.
Area of Science:
- Chemistry
- Molecular Spectroscopy
- Chirality Studies
Background:
- Resolving molecular chirality at the atomic scale is a significant challenge.
- Traditional Optical Circular Dichroism (OCD) spectroscopy struggles with localized structural features.
- Understanding atomic-level chiroptical signals is crucial for designing functional chiral molecules.
Purpose of the Study:
- To computationally investigate site-specific X-ray circular dichroism (XCD) for atomic-scale chirality analysis.
- To deconstruct and interpret chiroptical signals from trans-azobenzene derivatives.
- To establish a framework for engineering chiroptical responses and designing chiral systems.
Main Methods:
- Computational investigation of site-specific X-ray circular dichroism (XCD).
- Analysis of trans-azobenzene derivatives with varying chiral features.
- Modeling of dichroic contributions from local chiral centers and global molecular twists.
Main Results:
- XCD can differentiate contributions from local chiral centers and global molecular twists.
- Steric distortions can significantly influence or even suppress the XCD signal from chiral centers.
- Demonstrated interplay between local and global features influencing chiroptical signals.
Conclusions:
- Site-specific XCD provides atomic-level insights into molecular chirality.
- A new molecular design principle for tuning chiroptical activity is proposed.
- The framework supports the development of functional chiral systems with controlled conformational dynamics.
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