Revealing Local Structures of Chiral Molecules via X-ray Circular Dichroism

Abstract

Chirality is crucial due to its role in biological and chemical systems, where molecular handedness impacts structure and function. Chiral molecules with nonsuperimposable mirror images exhibit distinct biological activities pivotal in drug design and catalysis. This theoretical study explores X-ray circular dichroism (XCD) as a tool for probing the local structures of chiral molecules. We calculated the XCD signals at the chlorine, oxygen, and nitrogen K edges in various molecular systems. Our results show that electron delocalization plays an important role in the sensitivity of XCD to X-ray chromophore–chiral center distance. Furthermore, the XCD signals at multiple X-ray chromophores could offer multidimensional insights to pinpoint chiral center, providing spatial information about the local structures of complex chiral molecules.