Selective nanomechanics of aromatic versus aliphatic thiolates on gold surfaces

Thiolated gold nanointerfaces play a key role in numerous fields of science, technology, as well as modern medicine to coat, functionalize, and protect. Our computational study reveals that the mechanical vs thermal stabilities of aliphatic thiolates on gold surfaces are strikingly different from th...

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Bibliographic Details
Authors: Zoloff Michoff, Martin E., Ribas Ariño, Jordi, Marx, Dominik
Format: article
Status:Published version
Publication Date:2019
Country:España
Institution:Universidad de Barcelona
Repository:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/154885
Online Access:https://hdl.handle.net/2445/154885
Access Level:Open access
Keyword:Nanotecnologia
Oxidació
Nanotechnology
Oxidation
Description
Summary:Thiolated gold nanointerfaces play a key role in numerous fields of science, technology, as well as modern medicine to coat, functionalize, and protect. Our computational study reveals that the mechanical vs thermal stabilities of aliphatic thiolates on gold surfaces are strikingly different from those of aromatic thiolates. The aliphatic thiolates feature, at the same time, a higher thermal desorption energy but a lower mechanical rupture force than thiophenolates. Our analysis discloses that this most counterintuitive property is due to different mechanochemical detachment mechanisms. Electronic structure analyses along the detachment pathways trace this back to the distinct electronic properties of the S─Au bond in stretched nanojunctions. The discoveries that it is a higher thermal stability that entails a lower mechanical stability and that mechanical loads generate different local nanostructures depending on the nature of the thiolate are highly relevant for the rational design of improved thiol-gold nanocontacts.