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Abstract The origins of chirality and chiroptical properties in ligand‐protected gold and silver nanoparticles (NPs) are considered herein. Current conceptual models including the chiral core model, dissymmetric field model, and chiral footprint model are described as mechanisms that contribute to the understanding of chirality in these systems. Then, recent studies on thiolate‐stabilized gold NPs, phosphine‐stabilized gold NPs, multi‐ligand‐stabilized silver NPs, and DNA‐stabilized silver NPs are discussed. Insights into the origin of chiroptical properties including reasons for large Cotton effects in circular dichroism spectra are considered using both experimental and theoretical data available. Theoretical calculations using density functional theory (DFT) and time‐dependent DFT methods are found to be extremely useful for providing insights into the origin of chirality. The origin of chirality in ligand‐protected gold and silver NPs can be considered to be a complex phenomenon, arising from a combination of the three conceptual models.
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Chiral Systems Made from DNA
Abstract The very chemical structure of DNA that enables biological heredity and evolution has non‐trivial implications for the self‐organization of DNA molecules into larger assemblies and provides limitless opportunities for building functional nanostructures. This progress report discusses the natural organization of DNA into chiral structures and recent advances in creating synthetic chiral systems using DNA as a building material. How nucleic acid chirality naturally comes into play in a diverse array of situations is considered first, at length scales ranging from an individual nucleotide to entire chromosomes. Thereafter, chiral liquid crystal phases formed by dense DNA mixtures are discussed, including the ongoing efforts to understand their origins. The report then summarizes recent efforts directed toward building chiral structures, and other structures of complex topology, using the principle of DNA self‐assembly. Discussed last are existing and proposed functional man‐made nanostructures designed to either probe or harness DNA's chirality, from plasmonics and spintronics to biosensing.
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- Award ID(s):
- 1827346
- PAR ID:
- 10380616
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Science
- Volume:
- 8
- Issue:
- 5
- ISSN:
- 2198-3844
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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