We model the mechanical response of alkanethiol-passivated gold nanoparticle superlattice (supercrystal) at ambient and elevated pressures using large-scale molecular dynamics simulation. Because of the important roles of soft organic ligands in mechanical response, the supercrystals exhibit entropic viscoelasticity during compression at ambient pressure. Applying a hydrostatic pressure of seve...

Understanding how polyhedra pack into extended arrangements is integral to the design and discovery of crystalline materials at all length scales. Much progress has been made in enumerating and characterizing the packing of polyhedral shapes, and the self-assembly of polyhedral nanocrystals into ordered superstructures. However, directing the self-assembly of polyhedral nanocrystals into denses...

A series of group 11 m-terphenyl complexes have been synthesized via a metathesis reaction from the iron(II) (2,6-Mes2C6H3)2Fe and (2,6-Xyl2C6H3)2Fe (Mes = 2,4,6-Me3C6H2; Xyl 2,6-Me2C6H3). [2,6-Mes2C6H3M]2 (1, M Cu; 2, Ag; 6, Au) [2,6-Xyl2C6H3M]2 (3, 4, Ag) are dimeric in solid state, although different geometries observed depending on ligand. These feature short metal–metal distances expected ...

The geometric structures of ordered monolayers of large organic molecules (thiouracil) adsorbed to the surface of Ag(111) and graphite (0001) were analyzed using surface x-ray diffraction and scanning tunneling microscopy (STM), respectively. Although the substrates are different, in both cases the molecules are found to be arranged in parallel zig-zag rows. On graphite (0001) the molecules for...

We demonstrate assembly of spheroidal Ag nanoparticle clusters, chains and arrays induced by optical binding. Particles with diameters of 40 nm formed ordered clusters and chains in aqueous solution when illuminated by shaped optical fields with a wavelength of 800 nm; specifically, close-packed clusters were formed in cylindrically symmetric optical traps, and linear chains were formed in line...

We report coverage and temperature dependent bonding distances of vacuum-sublimed pentacene (PEN) submonolayers on Ag(111) obtained by the X-ray standing wave technique. The average vertical bonding distance of 2.98 Å at room temperature for 0.50 monolayer (ML) coverage increases to 3.12 Å for 0.75 ML due to competing intermolecular and adsorbate-substrate interactions. In contrast, decreasing ...

This project is an extension of TEM work conducted on a previous AINSE funded project AINGRA08066, and aims to use the TEM, STEM/HAADF, EDS and plasmon imaging facilities at ANSTO to structurally characterize novel supported silver nanoparticle catalysts for ozone abatement, and supported gold catalysts for low temperature CO oxidation. The catalysts, fabricated at the University of Auckland, c...

Self-assembling of nanocrystals involves organization of nanocrystals encapsulated by protective compact organic molecules into a crystalline material. The adsorbed molecules not only serve as the protection layer for the nanocrystals but also provide the dominant cohesive interactions (or “bonding”) sustaining the nanocrystal superlattices. The length of the adsorbed molecules is a controllabl...