Microscopic origin of chiral shape induction in achiral crystals

Abstract

In biomineralization, inorganic materials are formed with remarkable control of the shape and morphology. Chirality, as present in the biomolecular world, is therefore also common for biominerals. Biomacromolecules, like proteins and polysaccharides, are in direct contact with the mineral phase and act as modifiers during nucleation and crystal growth. Owing to their homochirality--they exist only as one of two possible mirror-symmetric isomers--their handedness is often transferred into the macroscopic shape of the biomineral crystals, but the way in which handedness is transmitted into achiral materials is not yet understood at the atomic level. By using the submolecular resolution capability of scanning tunnelling microscopy, supported by photoelectron diffraction and density functional theory, we show how the chiral 'buckybowl' hemibuckminsterfullerene arranges copper surface atoms in its vicinity into a chiral morphology. We anticipate that such new insight will find its way into materials synthesis techniques.

Chiral Buckybowl Molecules

“…Extension of π-conjugation through the outer rim of the corannulene provided a single chiral CNT [114]. Furthermore, the chiral island and nanowire ( Figure 20B) were found to form with different alignments of hemifullerenes.…”

“…Differing from the classical chiral assembly formation in a macroscopic organic system, chiral microscopic assemblies of buckybowl hemifullerene at the surface of inorganic crystal were achieved by Fasel and co-workers [114]. They discovered how chiral bowl-shape hemifullerenes, derivatives of sumanene ( Figure 20A), restructure on the copper surface atoms into chiral structures such as chiral nanowires and chiral islands.…”

“…They discovered how chiral bowl-shape hemifullerenes, derivatives of sumanene ( Figure 20A), restructure on the copper surface atoms into chiral structures such as chiral nanowires and chiral islands. Unlike other researchers using polar molecules with carbonyl groups as chiral surface modifiers [115,116], Fasel et al [114] turned their attention to metal-aromatic coordination bonds and found hemifullerenes suitable to induce chirality on a copper surface. Surprisingly, M enantiomers of hemifullerenes align along the [ ] direction, forming S kinks, which differs from the previously reported arrangement of C 60 /corannulene along the Cu [110] direction [2].…”

The Chain of Chirality Transfer as Determinant of Brain Functional Laterality. Breaking the Chirality Silence: Search for New Generation of Biomarkers; Relevance to Neurodegenerative Diseases, Cognitive Psychology, and Nutrition Science

“…Numerous experimental results demonstrate the transfer of chirality among different length scales ranging from dimensions of the elementary particles to the macro-scale (the length of the axon) [124]. In particular, it was shown that the chirality at the molecular scale (amino, acids, proteins, and polysaccharides) could be transferred to the macroscopic and macrolevel (neurofilaments and inorganic crystals) as shown in [168]. The issue of dimensionality in the chirality transfer effects is critical for brain information processing in the brain and artificial intelligence devices.…”

“…The chirality transfer (or the transfer of handedness) is observed between organic and inorganic molecular structure [168]. The central point of these studies is the chirality transfer in the variety of forms.…”