Scanning the Potential Energy Surface for Synthesis of Dendrimer-Wrapped Gold Clusters : Design Rules for True Single-Molecule Nanostructures

Thompson, Damien and Hermes, Jens P. and Quinn, Aidan J. and Mayor, Marcel. (2012) Scanning the Potential Energy Surface for Synthesis of Dendrimer-Wrapped Gold Clusters : Design Rules for True Single-Molecule Nanostructures. ACS Nano, 6 (4). pp. 3007-3017.

Full text not available from this repository.

Official URL: http://edoc.unibas.ch/dok/A6031588

Downloads: Statistics Overview


The formation of true single-molecule complexes between organic ligands and nanoparticles is challenging and requires careful design of molecules with size, shape, and chemical properties tailored for the specific nanoparticle. Here we use computer simulations to describe the atomic-scale structure, dynamics, and energetics of ligand-mediated synthesis and interlinking of 1 nm gold clusters. The models help explain recent experimental results and provide insight into how multidentate thioether dendrimers can be employed for synthesis of true single-ligand-nanoparticle complexes and also nanoparticle-molecule-nanoparticle 'dumbbell' nanostructures. Electronic structure calculations reveal the individually weak thioether-gold bonds (325 ± 36 meV), which act collectively through the multivalent (multisite) anchoring to stabilize the ligand-nanoparticle complex (ca. 7 eV total binding energy) and offset the conformational and solvation penalties involved in this 'wrapping' process. Molecular dynamics simulations show that the dendrimer is sufficiently flexible to tolerate the strained conformations and desolvation penalties involved in fully wrapping the particle, quantifying the subtle balance between covalent anchoring and noncovalent wrapping in the assembly of ligand-nanoparticle complexes. The computed preference for binding of a single dendrimer to the cluster reveals the prohibitively high dendrimer desolvation barrier (1.5 ± 0.5 eV) to form the alternative double-dendrimer structure. Finally, the models show formation of an additional electron transfer channel between nitrogen and gold for ligands with a central pyridine unit, which gives a stiff binding orientation and explains the recently measured larger interparticle distances for particles synthesized and interlinked using linear ligands with a central pyridine rather than a benzene moiety. The findings stress the importance of organic-inorganic interactions, the control of which is central to the rational engineering and eventual large-scale production of functional building blocks for nano(bio)electronics.
Faculties and Departments:05 Faculty of Science > Departement Chemie > Chemie > Molecular Devices and Materials (Mayor)
UniBasel Contributors:Mayor, Marcel and Hermes, Jens
Item Type:Article, refereed
Article Subtype:Research Article
Publisher:American Chemical Society
Note:Publication type according to Uni Basel Research Database: Journal article
Identification Number:
Last Modified:05 Apr 2017 11:55
Deposited On:08 Nov 2012 16:17

Repository Staff Only: item control page