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Particle analogs of electrons in colloidal crystals.

ABSTRACT: A versatile method for the design of colloidal crystals involves the use of DNA as a particle-directing ligand. With such systems, DNA-nanoparticle conjugates are considered programmable atom equivalents (PAEs), and design rules have been devised to engineer crystallization outcomes. This work shows that when reduced in size and DNA grafting density, PAEs behave as electron equivalents (EEs), roaming through and stabilizing the lattices defined by larger PAEs, as electrons do in metals in the classical picture. This discovery defines a new property of colloidal crystals-metallicity-that is characterized by the extent of EE delocalization and diffusion. As the number of strands increases or the temperature decreases, the EEs localize, which is structurally reminiscent of a metal-insulator transition. Colloidal crystal metallicity, therefore, provides new routes to metallic, intermetallic, and compound phases.

SUBMITTER: Girard M

PROVIDER: S-EPMC8237478 | biostudies-literature | 2019 Jun

REPOSITORIES: biostudies-literature

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Particle analogs of electrons in colloidal crystals.

Girard Martin M Wang Shunzhi S Du Jingshan S JS Das Anindita A Huang Ziyin Z Dravid Vinayak P VP Lee Byeongdu B Mirkin Chad A CA Olvera de la Cruz Monica M

Science (New York, N.Y.) 20190601 6446

A versatile method for the design of colloidal crystals involves the use of DNA as a particle-directing ligand. With such systems, DNA-nanoparticle conjugates are considered programmable atom equivalents (PAEs), and design rules have been devised to engineer crystallization outcomes. This work shows that when reduced in size and DNA grafting density, PAEs behave as electron equivalents (EEs), roaming through and stabilizing the lattices defined by larger PAEs, as electrons do in metals in the cl ...[more]

PMID: 31221857

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