Publications by authors named "Heather A Calcaterra"

We report a strategy to accelerate the synthesis and increase the crystallinity of colloidal crystals (CCs) engineered with DNA. Specifically, by holding the DNA-modified Au particle building blocks above the of the DNA bonding elements (i.e.

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Supercrystals of DNA-functionalized nanoparticles are visualized in three dimensions using X-ray ptychographic tomography, and their reciprocal spaces are mapped with small-angle X-ray scattering in order to better understand their internal defect structures. X-ray ptychographic tomography reveals various types of defects in an assembly that otherwise exhibits a single crystalline diffraction pattern. On average, supercrystals composed of smaller nanoparticles are smaller in size than supercrystals composed of larger particles.

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Reconfigurable, mechanically responsive crystalline materials are central components in many sensing, soft robotic, and energy conversion and storage devices. Crystalline materials can readily deform under various stimuli and the extent of recoverable deformation is highly dependent upon bond type. Indeed, for structures held together via simple electrostatic interactions, minimal deformations are tolerated.

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Semiconductors with chiral geometries at the nanoscale and mesoscale provide a rich materials platform for polarization optics, photocatalysis, and biomimetics. Unlike metallic and organic optical materials, the relationship between the geometry of chiral semiconductors and their chiroptical properties remains, however, vague. Homochiral ensembles of semiconductor helices with defined geometries open the road to understanding complex relationships between geometrical parameters and chiroptical properties of semiconductor materials.

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Nacre-like composites have been investigated typically in the form of coatings or free-standing sheets. They demonstrated remarkable mechanical properties and are used as ultrastrong materials but macroscale fibres with nacre-like organization can improve mechanical properties even further. The fiber form or nacre can, simplify manufacturing and offer new functional properties unknown yet for other forms of biomimetic materials.

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