Spring constant of a tuning-fork sensor for dynamic force microscopy

• Dennis van Vörden,
• Manfred Lange,
• Merlin Schmuck,
• Nico Schmidt and
• Rolf Möller

Beilstein J. Nanotechnol. 2012, 3, 809–816, doi:10.3762/bjnano.3.90

• evaluation of the spring constant was performed for a TF with a tip (e.g., a 25–100 μm tungsten wire) attached to the front face of the free prong of the tuning fork. It is connected separately through a metallic wire (e.g., a 25 μm gold wire) to collect the tunneling current, avoiding crosstalk with the

Plasmonics-based detection of H₂ and CO: discrimination between reducing gases facilitated by material control

• Gnanaprakash Dharmalingam,
• Nicholas A. Joy,
• Benjamin Grisafe and
• Michael A. Carpenter

Beilstein J. Nanotechnol. 2012, 3, 712–721, doi:10.3762/bjnano.3.81

• . The co-sputtered film was shown to have 9 atom % Au. Optical sensing apparatus The sensing apparatus used for the experiments is shown in Figure 9. The setup consists of, from right to left, an Ocean Optics tungsten halogen source with an emission wavelength range of 360–2500 nm; the quartz flow cell

Paper modified with ZnO nanorods – antimicrobial studies

• Mayuree Jaisai,
• Sunandan Baruah and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2012, 3, 684–691, doi:10.3762/bjnano.3.78

• conditions, i.e., in the dark, under light from a fluorescent lamp (1 klx), or under light from a tungsten–halogen lamp (1.2 klx). The intensity of light was kept comparable to standard room lighting conditions. Increase in zone of inhibition for E. coli and S. aureus with increasing incubation time under

Spontaneous dissociation of Co₂(CO)₈ and autocatalytic growth of Co on SiO₂: A combined experimental and theoretical investigation

• Kaliappan Muthukumar,
• Harald O. Jeschke,
• Roser Valentí,
• Evgeniya Begun,
• Johannes Schwenk,
• Fabrizio Porrati and
• Michael Huth

Beilstein J. Nanotechnol. 2012, 3, 546–555, doi:10.3762/bjnano.3.63

• bridging and terminal ligands are oriented towards the surface (Figure 7a), with distances to the surface of 2.08–2.39 Å. The obtained distances agree well with the recently reported hydrogen-bonding distance of tungsten carbonyls with the SiO2 substrate [33]. This configuration turns out to be the most

Imaging ultra thin layers with helium ion microscopy: Utilizing the channeling contrast mechanism

• Gregor Hlawacek,
• Vasilisa Veligura,
• Stefan Lorbek,
• Tijs F. Mocking,
• Antony George,
• Raoul van Gastel,
• Harold J. W. Zandvliet and
• Bene Poelsema

Beilstein J. Nanotechnol. 2012, 3, 507–512, doi:10.3762/bjnano.3.58

• the formation of cobalt nanoclusters, an atomically clean Ge{001} substrate was obtained by prolonged 800 eV Ar+ ion sputtering followed by annealing of the sample through resistive heating at 1100 K. Several monolayers of Co were evaporated by resistively heating a tungsten wire wrapped with a pure

Models of the interaction of metal tips with insulating surfaces

• Thomas Trevethan,
• Matthew Watkins and
• Alexander L. Shluger

Beilstein J. Nanotechnol. 2012, 3, 329–335, doi:10.3762/bjnano.3.37

• atomic resolution. Chromium and tungsten tips are used to image the NaCl(001) and MgO(001) surfaces. The interaction of the tips with the surface is simulated by using density-functional-theory calculations employing a mixed Gaussian and plane-wave basis and cluster-tip models. In each case, the apex of

• chromium and tungsten, which are chosen due to their common use in scanning-probe experiments. For several different combinations of tip and surface, we determine the tip–surface force field and the origin of the tip–surface interaction at close approach. These calculations employ cluster-tip models and

Junction formation of Cu₃BiS₃ investigated by Kelvin probe force microscopy and surface photovoltage measurements

• Fredy Mesa,
• William Chamorro,
• William Vallejo,
• Robert Baier,
• Thomas Dittrich,
• Alexander Grimm,
• Martha C. Lux-Steiner and
• Sascha Sadewasser

Beilstein J. Nanotechnol. 2012, 3, 277–284, doi:10.3762/bjnano.3.31

• metallic precursors evaporated from a tungsten boat for Zn and a tantalum effusion cell for sulfur. The substrate was heated to ~250 °C. A thickness monitor (Maxtec TM-400) with a quartz-crystal sensor was used to measure the deposition rate of Zn. The thickness of the films was ~120 nm, as measured with a

A measurement of the hysteresis loop in force-spectroscopy curves using a tuning-fork atomic force microscope

• Manfred Lange,
• Dennis van Vörden and
• Rolf Möller

Beilstein J. Nanotechnol. 2012, 3, 207–212, doi:10.3762/bjnano.3.23

• . This means that for a given tunneling current the attractive forces are stronger on the Ag/Si(111) √3 × √3 surface than on the PTCDA islands. Prior to the force-spectroscopy measurements the tungsten tip was prepared by making “soft contact” between the tip and a PTCDA island. Before and after the soft

Effect of the tip state during qPlus noncontact atomic force microscopy of Si(100) at 5 K: Probing the probe

• Adam Sweetman,
• Sam Jarvis,
• Rosanna Danza and
• Philip Moriarty

Beilstein J. Nanotechnol. 2012, 3, 25–32, doi:10.3762/bjnano.3.3

• 1200 °C, and then slow cooling from 900 °C to room temperature before being placed into the scan head. We introduced commercial qPlus sensors (Omicron GmbH), with an electrochemically etched tungsten wire attached to one tine of the tuning fork, into the scan head without any ex situ tip treatment. The

• silicon- rather than tungsten-terminated, and this assumption is supported by a combined scanning electron microscopy (SEM)/energy dispersive X-ray spectroscopy (EDX) study on an STM tip prepared by similar methods. We imaged at constant Δf, maintaining a constant oscillation amplitude (A0). All data

Generation and agglomeration behaviour of size-selected sub-nm iron clusters as catalysts for the growth of carbon nanotubes

• Ravi Joshi,
• Benjamin Waldschmidt,
• Jörg Engstler,
• Rolf Schäfer and
• Jörg J. Schneider

Beilstein J. Nanotechnol. 2011, 2, 734–739, doi:10.3762/bjnano.2.80

• either thermal evaporation (heating Al in a boron nitride crucible with a tungsten filament) or electron beam evaporation onto a commercial TEM grid (SiOx; Fa. Plano, Wetzlar). Aluminium buffer layer (10 nm) deposition was monitored by means of a quartz crystal microbalance (Cressington MTM 10). After

Deconvolution of the density of states of tip and sample through constant-current tunneling spectroscopy

• Holger Pfeifer,
• Berndt Koslowski and
• Paul Ziemann

Beilstein J. Nanotechnol. 2011, 2, 607–617, doi:10.3762/bjnano.2.64

• curves were recorded at different set currents by employing a lock-in technique with a modulation frequency of ~500 Hz, which is well above the bandwidth of the topographic feedback loop. As tunneling tip, we used an electrochemically etched tungsten wire, which was subsequently heated in UHV to ~2000 °C

Plasmonic nanostructures fabricated using nanosphere-lithography, soft-lithography and plasma etching

• Manuel R. Gonçalves,
• Taron Makaryan,
• Fabian Enderle,
• Stefan Wiedemann,
• Alfred Plettl,
• Othmar Marti and
• Paul Ziemann

Beilstein J. Nanotechnol. 2011, 2, 448–458, doi:10.3762/bjnano.2.49

• -ahesive film. The Cr masks were removed with a commercial etching solution (Chrome Etch 1 from SOTRAMCHEM Technic, France). Metal coating Gold films were deposited by physical vapor deposition (PVD), from tungsten boats, at a rate of 1 to 2 Å/s under a vacuum of 10−6 to 10−5 mbar. The thickness of the

Novel acridone-modified MCM-41 type silica: Synthesis, characterization and fluorescence tuning

• Maximilian Hemgesberg,
• Gunder Dörr,
• Yvonne Schmitt,
• Andreas Seifert,
• Zhou Zhou,
• Robin Klupp Taylor,
• Sarah Bay,
• Stefan Ernst,
• Markus Gerhards,
• Thomas J. J. Müller and
• Werner R. Thiel

Beilstein J. Nanotechnol. 2011, 2, 284–292, doi:10.3762/bjnano.2.33

• carried out on a Perkin–Elmer Lambda 18 double beam UV–vis spectrometer with double monochromator by setting the wavelength range from 200 nm to 900 nm in a 1 nm step width. The optical unit included a pre-aligned tungsten-halogen lamp and a deuterium lamp with automatic source exchange. All powder

Superhydrophobic surfaces of the water bug Notonecta glauca: a model for friction reduction and air retention

• Petra Ditsche-Kuru,
• Erik S. Schneider,
• Jan-Erik Melskotte,
• Martin Brede,
• Alfred Leder and
• Wilhelm Barthlott

Beilstein J. Nanotechnol. 2011, 2, 137–144, doi:10.3762/bjnano.2.17

• made holder [25][36], which allowed the examination of all sides. The specimens were examined with a Cambridge Stereoscan 200 scanning electron microscope (SEM) (Cambridge Instruments Ltd., Cambridge, UK) using a tungsten cathode and accelerating voltages between 5 and 15 kV. To determine structural

Switching adhesion forces by crossing the metal–insulator transition in Magnéli-type vanadium oxide crystals

• Bert Stegemann,
• Matthias Klemm,
• Siegfried Horn and
• Mathias Woydt

Beilstein J. Nanotechnol. 2011, 2, 59–65, doi:10.3762/bjnano.2.8

• metal–insulator transition (MIT) is the correlation of d band electrons of opposite spins as explained by the Mott–Hubbard model [3]. It was first recognized by Magnèli et al., that oxides of titanium and vanadium as well as those of molybdenum and tungsten form homologous series with planar faults of

Structure, morphology, and magnetic properties of Fe nanoparticles deposited onto single-crystalline surfaces

• Armin Kleibert,
• Wolfgang Rosellen,
• Mathias Getzlaff and
• Joachim Bansmann

Beilstein J. Nanotechnol. 2011, 2, 47–56, doi:10.3762/bjnano.2.6

• the interface and magnetic anisotropy energy in the particles. The RHEED data also show that the Fe particles on W(110) – despite of the large lattice mismatch between iron and tungsten – are not strained. Thus, strain is most likely not the origin of the enhanced orbital moments as supposed before

The description of friction of silicon MEMS with surface roughness: virtues and limitations of a stochastic Prandtl–Tomlinson model and the simulation of vibration-induced friction reduction

• W. Merlijn van Spengen,
• Viviane Turq and
• Joost W. M. Frenken

Beilstein J. Nanotechnol. 2010, 1, 163–171, doi:10.3762/bjnano.1.20

• surfaces often show very low friction coefficients (e.g., ~0.01 for a tungsten tip on graphite [1]), while macroscopically, usually friction coefficients above 0.1 are encountered. Hence it is not directly clear how the atomic-scale friction coefficients relate to their macroscopic counterparts. This

Magnetic coupling mechanisms in particle/thin film composite systems

• Giovanni A. Badini Confalonieri,
• Philipp Szary,
• Durgamadhab Mishra,
• Maria J. Benitez,
• Mathias Feyen,
• An Hui Lu,
• Leonardo Agudo,
• Gunther Eggeler,
• Oleg Petracic and
• Hartmut Zabel

Beilstein J. Nanotechnol. 2010, 1, 101–107, doi:10.3762/bjnano.1.12

• sample had to be coated with an approximately 3 µm thick layer of tungsten. Magnetic measurements were performed by means of superconducting quantum interference device (SQUID) magnetometry (Quantum Design, MPMS) on sample areas of 7 × 7 mm2, in a temperature range between 15 and 380 K, with the field

Enhanced visible light photocatalysis through fast crystallization of zinc oxide nanorods

• Sunandan Baruah,
• Mohammad Abbas Mahmood,
• Myo Tay Zar Myint,
• Tanujjal Bora and
• Joydeep Dutta

Beilstein J. Nanotechnol. 2010, 1, 14–20, doi:10.3762/bjnano.1.3

• and a glass slide (3 × 1 cm) with a coating of nanorods (Sample 1, Sample 2 and Sample 3) was placed inside the cuvette with the nanorod surface facing a tungsten-halogen light source (500 W). A glass vessel containing water was placed between the light source and the cuvettes to absorb the UV and