True nature of an archetypal self-assembly system: mobile Au-thiolate species on Au(111).
Alkanethiol self-assembled monolayer (SAM) phases on Au(111) have been assumed to involve direct S head group bonding to the substrate. Using x-ray standing wave experiments, we show the thiolate actually bonds to gold adatoms; self-organization in these archetypal SAM systems must therefore be governed by the movement of these Au-S-R moieties on the surface between two distinct local hollow sites on the surface. The results of recent ab initio total energy calculations provide strong support for this description, and a rationale for the implied significant molecular mobility in these systems.
Yu
Miao
M
Physics Department, University of Warwick, Coventry, UK.
Bovet
N
N
Satterley
Christopher J
CJ
Bengió
S
S
Lovelock
Kevin R J
KR
Milligan
P K
PK
Jones
Robert G
RG
Woodruff
D P
DP
Dhanak
V
V