Unveiling the nature of atomic defects in graphene on a metal surface

• Karl Rothe,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2024, 15, 416–425, doi:10.3762/bjnano.15.37

• by noble-gas ion irradiation [6][13][14][17][19][21][24], represents an opportunity for systematic defect studies. The work presented here was stimulated by the lack of experimental data on the actual geometry of atomic-scale defects in graphene. So far, scanning tunneling microscope (STM

• ) topographies have been claimed to be in accordance with, for example, single-C vacancy sites. However, clear-cut evidence for a missing C atom in the graphene lattice has remained elusive. Therefore, in addition to an STM, an atomic force microscope (AFM) has been used in the present study to unveil the

• geometric structure of the defect sites. Surprisingly, the smallest defect in graphene on Ir(111), which appears as a depression in STM images and, therefore, may readily be assigned to a single-C vacancy site, gives rise to an undistorted graphene lattice in AFM images. In contrast, slightly larger defects

Design, fabrication, and characterization of kinetic-inductive force sensors for scanning probe applications

• August K. Roos,
• Ermes Scarano,
• Elisabet K. Arvidsson,
• Erik Holmgren and
• David B. Haviland

Beilstein J. Nanotechnol. 2024, 15, 242–255, doi:10.3762/bjnano.15.23

• strip to connect the base of the cone to the Nb-Ti-N film, which is the ground plane of the microwave circuit. This feature enables the measurement of the tunneling current between the tip (grounded) when a DC bias is applied to a conductive sample surface. Scanning tunneling microscopy (STM) operation

• was verified both at room temperature and in a cryogenic environment. Thus, the deposited material is suitably conductive for STM and various electrostatic AFM techniques that require applying a low-frequency voltage to the tip. Mechanical mode Our chips were the same size as an AFM cantilever chip

Spatial variations of conductivity of self-assembled monolayers of dodecanethiol on Au/mica and Au/Si substrates

• Julian Skolaut,
• Jędrzej Tepper,
• Federica Galli,
• Wulf Wulfhekel and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2023, 14, 1169–1177, doi:10.3762/bjnano.14.97

• current maps after DDT SAM formation. The presence of a well-ordered SAM on the surface was confirmed by scanning tunneling microscopy (STM) images on alkanethiol-covered Au surfaces prepared in the same way, in which the individual molecules can be resolved, shown in Figure S4 in Supporting Information

• . A. Skolaut, ”Molecular Motor Based on Single Chiral Tripodal Molecules Studied with STM”, Doctoral Dissertation, Karlsruhe Institute of Technology, KIT Scientific Publishing, 2023. Funding This work was partly funded by the Netherlands Organisation for Scientific Research (NWO), grant 680.92.18.01

Two-dimensional molecular networks at the solid/liquid interface and the role of alkyl chains in their building blocks

• Suyi Liu,
• Yasuo Norikane and
• Yoshihiro Kikkawa

Beilstein J. Nanotechnol. 2023, 14, 872–892, doi:10.3762/bjnano.14.72

• coordination, halogen bonding, and dispersion forces [12][13][14][15][16][17][18][19][20][21][22]. Scanning tunneling microscopy (STM) is an important tool for the direct visualization of molecular arrangements, especially for two-dimensional (2D) networks. STM observations have been performed on atomically

• flat conducting substrates, such as metal surfaces and highly oriented pyrolytic graphite (HOPG), under ultrahigh vacuum (UHV) conditions, at solid/air or solid/liquid interfaces [23][24][25][26][27][28]. Although UHV-STM offers high-resolution imaging, it requires large, complex, and expensive

• instruments as well as thermally stable samples that do not decompose under sublimation during sample preparation. By contrast, STM at the solid/liquid interface is efficient for various sample types and requires only a simple apparatus [24]. Physisorbed monolayers at the solid/liquid interface have been

Current-induced mechanical torque in chiral molecular rotors

• Richard Korytár and
• Ferdinand Evers

Beilstein J. Nanotechnol. 2023, 14, 711–721, doi:10.3762/bjnano.14.57

• charge carrier and the mass of the helix per winding number. Keywords: molecular junctions; molecular motors; molecular switches; Introduction Experiments employing scanning tunneling microscopy (STM) have achieved the directed rotation of molecules controlled by an electrical current. Correspondingly

• unidirectional rotation in the STM setup requires a degree of symmetry breaking. There are two typical situations, that is, either the molecule by itself exhibits a handedness (chirality) or chirality is imposed by the geometry of the molecular junction [6][10]. The purpose of this article is to provide a

• potential minimum or its motion is unbound. In Figure 9 in the Appendix section, we have plotted the critical parameters m/M, , and N. Helix under a current The threshold ratio m/M1 = 1/6 is too high to be achieved in molecules in a STM. However, we can make it more favorable if we consider the helix under

Molecular nanoarchitectonics: unification of nanotechnology and molecular/materials science

• Katsuhiko Ariga

Beilstein J. Nanotechnol. 2023, 14, 434–453, doi:10.3762/bjnano.14.35

• oligomeric chains were significantly elongated. High-resolution scanning tunneling microscope (STM) topography shows alternating bright twin spots, which correspond to phenylene and tetrafluorophenylene, respectively. A high-resolution atomic force microscope (AFM) image of an entirely elongated fine

• synthesize 8-carbon armchair graphene nanoribbons and nanographene C66 with periodic vacancies on the surface (Figure 8) [124]. Detailed processes of the surface synthesis of 5,8-dibromobenzene molecules kept at room temperature after deposition on Au(111) were disclosed through STM observations

• precursor caused macrocyclization, resulting in a polyphenylene dendrimer. Further annealing at 623 K for 2 min resulted in surface-assisted cyclic hydrogenation and eventual conversion to the target zigzag coronoid C144. A magnified STM image of zigzag coronoid C144 reveals a hexagonal graphene nanoflake

From a free electron gas to confined states: A mixed island of PTCDA and copper phthalocyanine on Ag(111)

• Alfred J. Weymouth,
• Emily Roche and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2022, 13, 1572–1577, doi:10.3762/bjnano.13.131

• of one-dimensional quantum wells, our analysis shows that this state does not act as a free electron gas and that the features are instead localized above individual PTCDA molecules. Keywords: AFM; copper phthalocyanine; dI/dV; PTCDA; STM; Introduction Organic semiconductor devices typically

• -precision STM and atomic force microscopy (AFM) scanning. Third, CuPc and PTCDA are known to form commensurate phases on flat metal surfaces. In particular, they have been well studied at different stoichiometries on Ag(111) [16]. Henneke and co-workers showed that more than 0.15 ML of PTCDA in addition to

• to CuPc within each unit cell, called the P2C phase [16]. A STM and AFM investigation of single CuPc and PTCDA molecules on a thin insulating layer interestingly showed little change of the dI/dV spectra (features shifted, but were preserved) or of the corresponding dI/dV images when the two

Studies of probe tip materials by atomic force microscopy: a review

• Ke Xu and
• Yuzhe Liu

Beilstein J. Nanotechnol. 2022, 13, 1256–1267, doi:10.3762/bjnano.13.104

• shown to be removed one by one from the sample surface by tip indentation of the scanning tunneling microscope (STM). The probing of the interaction forces by AFM and thus the analysis of van der Waals (vdW) forces can provide valuable information on the evolution of the tip size. Carbon nanotube probes

Design of surface nanostructures for chirality sensing based on quartz crystal microbalance

• Yinglin Ma,
• Xiangyun Xiao and
• Qingmin Ji

Beilstein J. Nanotechnol. 2022, 13, 1201–1219, doi:10.3762/bjnano.13.100

• expose chiral surfaces even with high symmetry and low Miller index surface orientations [131][132][133]. Therefore, metals with chiral surfaces may have enantiospecific interactions with chiral molecules [134][135][136][137][138]. Scanning tunneling microscopy (STM) studies and simulations indicated

• al. proved by STM the molecular-level identification of a chiral recognition process of phthalocyanine (Pc) on a Cu(100) surface [139]. They revealed the critical role of the particular adsorption geometry on the metal surface in the chiral-specific configuration of Pc. Kong and co-workers

A cantilever-based, ultrahigh-vacuum, low-temperature scanning probe instrument for multidimensional scanning force microscopy

• Hao Liu,
• Zuned Ahmed,
• Sasa Vranjkovic,
• Manfred Parschau,
• Andrada-Oana Mandru and
• Hans J. Hug

Beilstein J. Nanotechnol. 2022, 13, 1120–1140, doi:10.3762/bjnano.13.95

• scanning tunneling microscope (STM) can be transformed into a tuning fork-based AFM simply by replacing the rigid STM tip by a tuning fork with an attached tip and by adding an extra pre-amplifier and a PLL to drive the tuning fork oscillation and measure shifts in its resonance frequency arising from the

• noise and measurement bandwidths”, and “STM noise spectrum and tip–sample gap stability measurements”. Finally, various atomic-scale STM and AFM results described in section “Results and Discussion” structured into various subsections demonstrate the performance of our new AFM for such work. The last

• with a reflectivity of typically 4%. This limits the sensitivity of the interferometer to about 89 fm/, (see section “Results and Discussion” for the characterization of the interferometric deflection sensor). Figure 3a shows a typical setup for a UHV STM or tuning fork-based AFM. Preferably, the low

Self-assembly of C₆₀ on a ZnTPP/Fe(001)–p(1 × 1)O substrate: observation of a quasi-freestanding C₆₀ monolayer

• Guglielmo Albani,
• Michele Capra,
• Alessandro Lodesani,
• Alberto Calloni,
• Gianlorenzo Bussetti,
• Marco Finazzi,
• Franco Ciccacci,
• Alberto Brambilla,
• Lamberto Duò and
• Andrea Picone

Beilstein J. Nanotechnol. 2022, 13, 857–864, doi:10.3762/bjnano.13.76

• sublimated by Knudsen effusion cells. The deposition flux was 0.5 ML/min, with 1 ML = 3.06 Å, as monitored by a quartz microbalance. C60 was evaporated on top of 1 ML ZnTPP/Fe(001)–p(1 × 1)O. STM images have been acquired at room temperature in constant-current mode with custom-made electrochemically etched

• W tips. Scanning tunneling spectroscopy (STS) data, that is, dI/dV curves for the investigation of the sample density of states (DOS), have been collected at room temperature, using a lock-in amplifier with a modulation amplitude of 60 mV. All STM and STS measurements have been carried out while

• with previous results [46]. This order extends over large domains (hundreds of square nanometers wide) and tends to disappear as soon as additional molecules are deposited on top of the wetting layer. The formation of a well-ordered ZnTPP film with (5 × 5) periodicity is confirmed by the STM image

Direct measurement of surface photovoltage by AC bias Kelvin probe force microscopy

• Masato Miyazaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2022, 13, 712–720, doi:10.3762/bjnano.13.63

• (HF2LI with PID option, Zurich Instruments) to generate and control the AC bias. The typical sensitivity of our measurements was estimated to be δV = 1 mV (see Appendix). We simultaneously measured the tunneling current through the I/V converter as scanning tunneling microscopy (STM) [34] to consider the

Investigation of electron-induced cross-linking of self-assembled monolayers by scanning tunneling microscopy

• Patrick Stohmann,
• Sascha Koch,
• Yang Yang,
• Christopher David Kaiser,
• Julian Ehrens,
• Jürgen Schnack,
• Niklas Biere,
• Dario Anselmetti,
• Armin Gölzhäuser and
• Xianghui Zhang

Beilstein J. Nanotechnol. 2022, 13, 462–471, doi:10.3762/bjnano.13.39

• collision, rotational or vibrational transitions, electron attachment, electronic excitation, and ionization [4][5]. Oriented molecular layers on surfaces are particularly well suited for such studies as surface analytical tools, such as scanning tunneling microscopy (STM), allow for detailed observations

• the initial stage of cross-linking, the SAMs are exposed to 50 and 1 keV electrons at very low doses and subsequently imaged by STM. The electron dose is then gradually increased up to doses of 25 mC/cm2 and the electron-induced structural changes were then determined. Results and Discussion The

• were first imaged by STM, then exposed to 1 keV or 50 eV electrons at a series of doses, and imaged again by STM (see Figure 1). Characterization of TPT SAMs on Au(111) The TPT SAMs prepared from dimethylformamide (DMF)-based solution display two molecular arrangements: the α-phase and the β-phase

Thermal oxidation process on Si(113)-(3 × 2) investigated using high-temperature scanning tunneling microscopy

• Hiroya Tanaka,
• Shinya Ohno,
• Kazushi Miki and
• Masatoshi Tanaka

Beilstein J. Nanotechnol. 2022, 13, 172–181, doi:10.3762/bjnano.13.12

• Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan 10.3762/bjnano.13.12 Abstract Thermal oxidation of Si(113) in a monolayer regime was investigated using high-temperature scanning tunneling microscopy (STM). Dynamic processes during thermal oxidation were examined in three

• the literature. Initial oxidation processes were identified based on high-resolution STM images. Keywords: high-index Si surface; in situ measurement; oxidation; scanning tunneling microscopy (STM); Introduction High-index silicon surfaces have drawn considerable interest for their usefulness in

• experimental challenge toward elucidating the dynamic processes in oxidation. For example, the formation processes of iron oxide nanoparticles have been studied in detail using state-of-the-art X-ray scattering methods [4]. As a complementary method, variable-temperature scanning tunneling microscopy (VT-STM

Effect of lubricants on the rotational transmission between solid-state gears

• Huang-Hsiang Lin,
• Jonathan Heinze,
• Alexander Croy,
• Rafael Gutiérrez and
• Gianaurelio Cuniberti

Beilstein J. Nanotechnol. 2022, 13, 54–62, doi:10.3762/bjnano.13.3

• situation becomes very different since a continuum description of the materials might not be sufficient. The development of the atomic force microscope (AFM) [19] and the scanning tunneling microscope (STM) [20][21] has allowed for visualization and manipulation of nanoscale gears [22]. Those gears can be

Topographic signatures and manipulations of Fe atoms, CO molecules and NaCl islands on superconducting Pb(111)

• Carl Drechsel,
• Philipp D’Astolfo,
• Jung-Ching Liu,
• Thilo Glatzel,
• Rémy Pawlak and
• Ernst Meyer

Beilstein J. Nanotechnol. 2022, 13, 1–9, doi:10.3762/bjnano.13.1

• with functionalized tips. We report on the topographic signatures observed by scanning tunneling microscopy (STM) of carbon monoxide (CO) molecules, iron (Fe) atoms and sodium chloride (NaCl) islands deposited on superconducting Pb(111). For the CO adsorption a comparison with the Pb(110) substrate is

• microscopy (STM) and atomic force microscopy (AFM) are required to accurately disentangle structural and electronic properties of atomic or molecular structures on these superconducting platforms. STM/AFM generally allows for a controlled repositioning of adsorbates, both by lateral and vertical

• enable the development of functionalized tips, obtained by picking up a single molecule from a surface. This has been an important milestone for low-temperature STM/AFM techniques since the CO tip nowadays enables systematic high-resolution measurements of surfaces, molecules and atoms [33][34][35]. It

Impact of electron–phonon coupling on electron transport through T-shaped arrangements of quantum dots in the Kondo regime

• Patryk Florków and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2021, 12, 1209–1225, doi:10.3762/bjnano.12.89

• , STM experiments presenting asymmetric satellite lines indicate the role of interference [51]. From the line widths of the central peaks or widths of satellite resonances one can infer about the Kondo temperature. In agreement with our calculations, it is observed, that TK increases with a weakening of

Irradiation-driven molecular dynamics simulation of the FEBID process for Pt(PF₃)₄

• Alexey Prosvetov,
• Alexey V. Verkhovtsev,
• Gennady Sushko and
• Andrey V. Solov’yov

Beilstein J. Nanotechnol. 2021, 12, 1151–1172, doi:10.3762/bjnano.12.86

Molecular assemblies on surfaces: towards physical and electronic decoupling of organic molecules

• Sabine Maier and
• Meike Stöhr

Beilstein J. Nanotechnol. 2021, 12, 950–956, doi:10.3762/bjnano.12.71

• these decoupling layers to the organic molecules and vice versa. This has the great advantage that these systems can still be examined by scanning tunneling microscopy (STM) and spectroscopy (STS), which gives insight into structural and electronic properties of individual molecules. For applications

• monitor the STM-induced nucleation, growth, and ripening of self-assembled monolayers in a more controlled fashion. Söngen et al. [77] provide insight into the interaction of organic molecules with bulk insulators by discussing the adsorption of ethanol on both calcite and magnesite using three

• otherwise only achieved for multilayers on the bare Ni. On hBN/Cu(111), Zimmermann et al. [87] could visualize the molecular orbitals of pyrene derivatives by STM at the submolecular level, while Brülke et al. [88] measured the fluorescence of monolayer perylenetetracarboxylic dianhydride (PTCDA), which is

The role of convolutional neural networks in scanning probe microscopy: a review

• Ido Azuri,
• Irit Rosenhek-Goldian,
• Neta Regev-Rudzki,
• Georg Fantner and
• Sidney R. Cohen

Beilstein J. Nanotechnol. 2021, 12, 878–901, doi:10.3762/bjnano.12.66

• was trained on simulated STEM images. Then, scanning tunneling microscopy (STM) images of the same sample were used to characterize the defects. STM images, which give the local density of states, measure not only the Si lattice, but also defect areas where this well-ordered lattice disappears. Such

Local stiffness and work function variations of hexagonal boron nitride on Cu(111)

• Abhishek Grewal,
• Yuqi Wang,
• Matthias Münks,
• Klaus Kern and
• Markus Ternes

Beilstein J. Nanotechnol. 2021, 12, 559–565, doi:10.3762/bjnano.12.46

• ) [19][20], strain-induced highly corrugated layers for h-BN/Rh(111) [21][22][23], and template layers for molecules with strong local variations of the work function for h-BN/Ir(111) [24] are representative of such morphological diversity. We use low-temperature combined scanning tunnelling (STM) and

• non-contact atomic force microscopy (nc-AFM) to study h-BN on Cu(111). This template has interesting properties because the dielectric layer is only very weakly bound to the metal and shows an electronically induced Moiré superstructure [25][26]. First STM studies on this system pointed to only a

• ]. Recently, however, Zhang et al. used STM in combination with DFT simulations to study the variation of the local work function and bandgap within the Moiré superlattice and found that the variation depends on the angle of the Moiré with respect to the substrate lattice, but inferred only marginal structure

Determining amplitude and tilt of a lateral force microscopy sensor

• Oliver Gretz,
• Alfred J. Weymouth,
• Thomas Holzmann,
• Korbinian Pürckhauer and
• Franz J. Giessibl

Beilstein J. Nanotechnol. 2021, 12, 517–524, doi:10.3762/bjnano.12.42

• the acquired data. To determine the amplitude and tilt we make use of the scanning tunneling microscopy (STM) channel and acquire data without and with oscillation of the tip above a local surface feature. We use a full two-dimensional current map of the STM data without oscillation to simulate data

• is called lateral force microscopy (LFM) (Figure 1). One advantage to LFM is that it is highly sensitive to short-range interactions. A drawback is that it is not a suitable technique for approaching a sample or determining the sample tilt. Here a complementary technique such as STM (used in our

• , however, does not take the real geometry of the sensor and electrodes into account. At low temperatures, the most common method is to use STM to calibrate the amplitude, provided that STM is available and that the sample is conducting. This method is often used for normal AFM, where the cantilever

Extended iron phthalocyanine islands self-assembled on a Ge(001):H surface

• Rafal Zuzak,
• Marek Szymonski and
• Szymon Godlewski

Beilstein J. Nanotechnol. 2021, 12, 232–241, doi:10.3762/bjnano.12.19

• nanoislands. Our STM data indicate that FePc molecules stay intact upon adsorption. While single molecules are trapped at surface defects and could be manipulated with the STM tip away from the defects onto the perfectly hydrogenated Ge(001):H surface, the major fraction of the molecules could be found within

• single-layer islands extending surprisingly far over distances reaching hundreds of nanometers. Within these islands FePc molecules adopt an upright orientation, which is characteristic for substrates weekly interacting with metal phthalocyanines. Our combined scanning tunneling microscopy (STM) and

• bond dimer (DBD) is formed. A typical STM appearance of the Ge(001):H surface with the above atomic-scale defects is shown in Figure 1. Molecular islands of FePc on Ge(001):H After deposition of FePc molecules onto a Ge(001):H surface at room temperature, we observe single molecules distributed over

TiO_x/Pt₃Ti(111) surface-directed formation of electronically responsive supramolecular assemblies of tungsten oxide clusters

• Marco Moors,
• Yun An,
• Agnieszka Kuc and
• Kirill Yu. Monakhov

Beilstein J. Nanotechnol. 2021, 12, 203–212, doi:10.3762/bjnano.12.16

• surfaces by using high-resolution scanning tunneling microscopy (STM), in particular on TiO2(110) [15][16], CuO(110) [17], and Pt(111) [18]. Recently, the surface behavior of W3O9 was assessed on a complex CuWO3 phase grown on Cu(110). The CuWO3/Cu(110) substrate can be viewed as a two-dimensional (2D

• , theory-supported STM measurements at liquid nitrogen temperatures have been selected as an ideal characterization technique. This is due to the fact that it not only allows high-resolution imaging on the nanoscale, but the STM tip may also act as a charge-injecting or depleting electrode for the

• controlled manipulation of single W3O9 clusters. The power of the STM approach for molecular switches has been demonstrated several times. For example, Cui et al. recently showed the reversible switching of a large discoid polyaromatic salt as a function of the applied bias voltage [27]. By that, we were

Direct observation of the Si(110)-(16×2) surface reconstruction by atomic force microscopy

• Tatsuya Yamamoto,
• Ryo Izumi,
• Kazushi Miki,
• Takahiro Yamasaki,
• Yasuhiro Sugawara and
• Yan Jun Li

Beilstein J. Nanotechnol. 2020, 11, 1750–1756, doi:10.3762/bjnano.11.157

• . The pentagonal structure, which is the most important building block of the reconstruction, was concluded to consist of five atoms, while only four or five spots (depending on tip bias) have been reported with scanning tunneling microscopy (STM). Single atoms were determined to exist near step edges

• between upper and lower terraces, which have not been reported using STM. These findings are key evidence for establishing an atomic model of the Si(110)-(16×2) reconstruction, which indeed has a complex structure. Keywords: atomic force microscopy (AFM); noncontact atomic force microscopy (NC-AFM); Si

• ], scanning tunneling microscopy (STM) [15][16][17][18][19][20][21][22][23][24], scanning transmission electron microscopy (STEM) [25], and photoelectron spectroscopy (PES) [22][26][27]. The 16×2 reconstruction has a striped structure with upper and lower terraces and with boundaries of monatomic steps. In