6 / 19
allied
academies
Materials-Metals 2017
Page 18
November 16-17, 2017 Paris, France
13
th
Annual Conference on
Materials Science, Metal and Manufacturing
Journal of Materials Science and Nanotechnology
Volume 1 Issue 2
Silvia Karthäuser, Mater Sci Nanotechnol 2017, 1:2
Interface-driven formation of a two-dimensional
dodecagonal fullerene quasi crystal
Silvia Karthäuser
Forschungszentrum Jülich GmbH, Germany
C
lose-packed monolayers of Buckminsterfullerenes (C
60
) on
metallic substrates are very rich systems with respect to their
rotational degrees of freedom and possible interactions with
different adsorption sites or next neighbors. They have attracted
much attention due to their structural and electronic properties.
Here, we focus on the ability of C
60
to form self-assembled
monolayers that mirror impressively the electronic properties of
the respective substrate. Using low-temperature UHV-STM and
STS in combination with DFT calculations the interactions of C
60
molecules with a metallic surface, an alloy, and a thin titanium
oxide film are characterized in detail. The LT-STM images with
highly resolved orbital structure allow a detailed assignment
of the C
60
adsorption orientation and geometry with respect to
the underlying substrate. Moreover, even second order interface
effects, that is, interactions of C
60
with atoms of the subsurface
layer are identified. Most interestingly, in the case of a Pt
3
Ti-single
crystal alloy used as substrate the influence of subsurface Ti-
atoms on the self-assembly behavior of fullerenes is determined.
By employing DFT calculations, the preferred adsorption sites
of the fullerenes have been identified. Here, third layer Ti-atoms
provoke an adsorption energy landscape of the Pt
3
Ti-single
crystal alloy so that the C
60
/alloy interfacial interactions result
in the formation of a two-dimensional dodecagonal fullerene
quasicrystal, which can be described in terms of a square-triangle
tiling.
Figure 1:
Dodecagonal square-triangle tiling, as measured by
STM. (a) High-resolution UHV-STM image of C
60
on 2Pt-
Pt
3
Ti(111) (scale bar: 3 nm). One dodecagon and two local
structures are indicated in white. (b) Square-triangle tiling
extracted from a), with color-coded decomposition into different
types of approximants.
Recent Publications
• PaßensM,Waser R, Karthäuser S (2015) Enhanced fullerene-
Au(111) coupling in (2√3
x
2√3)R30°-superstructures
with cooperative intermolecular interactions. Beilstein J.
Nanotechnol. 6: 1421-1431.
• PaßensM,Karthäuser S (2015) Interfacial and intermolecular
interactions determining the rotational orientation of C
60
adsorbed on Au(111). Surf. Sci. 642: 11-15.
• Paßens M, Caciuc V, Atodiresei N, Moors M, Blügel S,
Waser R, Karthäuser S (2016) Tuning the surface electronic
structure of a Pt
3
Ti(111) electro catalyst. Nanoscale 8:
13924-13933.
• Paßens M, Moors M, Waser R, Karthäuser S (2017) Energy
level alignment at the fullerene/titanium oxide ultrathin
film interface. J. Phys. Chem. C 121: 2815-2821.
• Paßens M, Caciuc V, Atodiresei N, Feuerbacher M, Moors
M, Dunin-Borkowski R E, Blügel S, Waser R, Karthäuser
S (2017) Interface-driven formation of a two-dimensional
dodecagonal fullerene quasicrystal. Nat. Commun. 8: 15367.
Biography
Silvia Karthäuser has her expertise in the self-assembly of organic molecules
and nanomaterials on surfaces; surface analysis and electronic transport
phenomena with spectroscopic and scanning-probe methods; design,
fabrication and electronic characterization of novel nano-electronic test devices.
Special interest: phenomena at organic-metal or organic-semiconductor
interfaces; chemical structure – electronic property relationship of functional
organic molecules; addressing molecular structures by external triggers, e. g.
electronic or photonic.
s.karthaeuser@fz-juelich.de