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Updated: Nov 27, 2025
Monitoring Protein Adsorption with Solid-state Nanopores
Published on: December 2, 2011
Ligand structure and adsorption free energy of nanocrystals on solid substrates
Matthew Pham1, Alex Travesset2
1Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011, USA.
Abstract:
We present an investigation on the absorption of alkylthiolated nanocrystals on a solid substrate. We calculate adsorption free energies and report a number of effects induced by the substrate. Nearest neighbor distances and bonding free energies are significantly different than for a free floating case, there is a weakening of bonding free energies among nanocrystals, and the adsorption is manifestly anisotropic, i.e., stronger along certain directions of the nanocrystal core. We contend that this last result accounts for the Bain transition (fcc → bcc) observed in experimental results. We report the presence of vortices induced by the substrate, which explain the increased nearest neighbor distance among nanocrystals, which is in excellent quantitative agreement with experimental results and with the predictions of the Orbifold Topological Model. Implications for the assembly of nanostructures and future experiments are also discussed.
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