58 research outputs found
Spontaneous breaking and re-making of the RS-Au-SR staple in self-assembled ethylthiolate/Au(111) interface
The stability of
the self-assembled RS–Au–SR (R =
CH<sub>2</sub>CH<sub>3</sub>)/AuÂ(111) interface at room temperature
has been investigated using scanning tunneling microscopy (STM) in
conjunction with density functional theory (DFT) and MD calculations.
The RS–Au–SR staple, also known as Au-adatom-dithiolate,
assembles into staple rows along the [112Ě…] direction. STM imaging
reveals that while the staple rows are able to maintain a static global
structure, individual staples within the row are subjected to constant
breaking and remaking of the Au–SR bond. The C<sub>2</sub>S–Au–SC<sub>2</sub>/AuÂ(111) interface is under a dynamic equilibrium and it is
far from rigid. DFT/MD calculations show that a transient RS–Au–Au–SR
complex can be formed when a free Au atom is added to the RS–Au–SR
staple. The relatively high reactivity of the RS–Au–SR
staple at room temperature could explain the reactivity of thiolate-protected
Au nanoclusters, such as their ability to participate in ligand exchange
and intercluster reactions
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