Formation and development of nanometer-sized cybotactic clusters in bent-core nematic liquid crystalline compounds

• Yuri P. Panarin,
• Sithara P. Sreenilayam,
• Jagdish K. Vij,
• Anne Lehmann and
• Carsten Tschierske

Beilstein J. Nanotechnol. 2018, 9, 1288–1296, doi:10.3762/bjnano.9.121

• dielectric strength and relaxation frequency for these processes are shown to give rise to sharpness in cluster boundaries, increased size and volume fraction in the LC nematic phase. The effect of the bias field on the LC cell is similar to reducing its temperature; both variables increase the cluster size

• and volume fraction and give rise to sharp cluster boundaries. The findings confirm that dielectric spectroscopy is a powerful and an extremely useful technique to provide a deeper understanding of the mechanism of cybotactic cluster formation in the isotropic liquid and the nematic phase of LCs as a

• correlations among the neighboring molecules were revealed and the cybotactic clusters were established [35][36][48]. This was the first successful attempt for determining the cluster size by using the Maier–Meier equations using dielectric parameters such as anisotropic permittivity and the anisotropic

Atomistic modeling of tribological properties of Pd and Al nanoparticles on a graphene surface

• Alexei Khomenko,
• Miroslav Zakharov,
• Denis Boyko and
• Bo N. J. Persson

Beilstein J. Nanotechnol. 2018, 9, 1239–1246, doi:10.3762/bjnano.9.115

• the metallic clusters is much stronger (in particular for the Pd cluster) than the interaction potential between a metal atom and the graphene carbon atoms, it is likely that the ordered domains of metal atoms are not commensurate with the graphene lattice at any point during slip. Nevertheless

Comparative study of antibacterial properties of polystyrene films with TiO_x and Cu nanoparticles fabricated using cluster beam technique

• Vladimir N. Popok,
• Cesarino M. Jeppesen,
• Peter Fojan,
• Anna Kuzminova,
• Jan Hanuš and
• Ondřej Kylián

Beilstein J. Nanotechnol. 2018, 9, 861–869, doi:10.3762/bjnano.9.80

• describes a novel approach for the formation of bactericidal polymer thin films (polystyrene in this case), produced by spin-coating, with Ti and Cu NPs deposited from cluster beams. Ti NPs are treated in three different ways in order to study different approaches for oxidation and, thus, efficiency in

• same composite films making the suggested approach attractive for the cases requiring reusable polymer-based antibacterial media. Keywords: antibacterial properties; cluster beam technique; nanoparticles; polymers; Introduction Certain metals, when present in excess, become destructive or lethal to

• resistant against washing out in procedures. It has recently been shown that the deposition of metal NPs using the cluster beam technique is an efficient approach in the formation of polymer composite films with antibacterial properties. The composites can be formed by either incorporation of particles

Effect of microtrichia on the interlocking mechanism in the Asian ladybeetle, Harmonia axyridis (Coleoptera: Coccinellidae)

• Jiyu Sun,
• Chao Liu,
• Bharat Bhushan,
• Wei Wu and
• Jin Tong

Beilstein J. Nanotechnol. 2018, 9, 812–823, doi:10.3762/bjnano.9.75

• changes in the middle of the abdomen. The density of the microtrichia changed from sparse to dense in each abdominal segment (shown in Figure 4b–d), and the number of microtrichia in each cluster gradually increased from single to multiple, corresponding to the change in density (Figure 4e–h). The spacing

• and functions. The arrangement of microtrichia on the abdominal terga exhibits a cyclical change in the middle of the abdomen. The density of the microtrichia shifts from sparse to dense in each abdominal segment, and the number of microtrichia in each cluster gradually increased from single to

• microtrichial arrangement on the middle of the abdomen; (j, k) the microtrichia on both sides of the abdomen; (j) the lateral margin; (k) part of the spicule patch; (i) part of the palisade fringe at the posterior margin of the tergum; (e, f, g, h) the number of microtrichia in each cluster gradually increases

Dynamics and fragmentation mechanism of (C₅H₄CH₃)Pt(CH₃)₃ on SiO₂ surfaces

• Kaliappan Muthukumar,
• Harald O. Jeschke and
• Roser Valentí

Beilstein J. Nanotechnol. 2018, 9, 711–720, doi:10.3762/bjnano.9.66

• simulated. For this purpose, a representative simple cluster model Si(OH)3 is considered. Although this does not account for the complete surface model, it is a good approximation to evaluate the reaction barriers for different reactions observed through the MD simulations. In the literature, such a simple

• )Pt(CH3)3 on SiO2 surfaces show that the dissociation begins with either the detachment of methyl groups or of the methylcyclopentadienyl ring. In the cluster model, the interaction of (C5H4CH3)Pt(CH3)3 with the surface Si atoms, has a barrier of 0.140 eV, when (C5H4CH3)Pt(CH3)3 interacts through the

• the elimination of methyl groups two surface active sites are necessary, and the model used here limits the computation of the reaction barriers to such cases. Possible pathways by which Pt(CH3)3 gets dissociated on the model cluster, in the presence and absence of O2 , are derived and shown in Scheme

Anchoring of a dye precursor on NiO(001) studied by non-contact atomic force microscopy

• Sara Freund,
• Antoine Hinaut,
• Nathalie Marinakis,
• Edwin C. Constable,
• Ernst Meyer,
• Catherine E. Housecroft and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2018, 9, 242–249, doi:10.3762/bjnano.9.26

• atomic rows of the substrate for this particular type of cluster is visible as observed for single molecules (see Figure 3e). Each DCPDMbpy in a cluster appears to lie flat implying that the adsorption geometry of the molecule on NiO(001) is the same when adsorbing as a single molecule or when forming

• clusters. One of the windmill-shaped clusters is resolved in Figure 4b,c. The topographic image (Figure 4b) shows clearly that the cluster is composed of four distinct molecules. Figure 4c, which was recorded during the second pass with a Z-offset of −350 pm, presents the same cluster with intramolecular

• chiralities. In fact, like many other molecules, DCPDMbpy is prochiral, when confined in two dimensions [61][62][63][64][65], implying the appearance of the surface enantiomers: α-DCPDMbpy and β-DCPDMbp (Figure 4d). In the case of the specific cluster imaged in Figure 4c it can be seen that the molecules A, B

Bombyx mori silk/titania/gold hybrid materials for photocatalytic water splitting: combining renewable raw materials with clean fuels

• Stefanie Krüger,
• Michael Schwarze,
• Otto Baumann,
• Christina Günter,
• Michael Bruns,
• Christian Kübel,
• Dorothée Vinga Szabó,
• Rafael Meinusch,
• Verónica de Zea Bermudez and
• Andreas Taubert

Beilstein J. Nanotechnol. 2018, 9, 187–204, doi:10.3762/bjnano.9.21

• (Figure 3). Although the primary particles roughly have the same size in all samples, there are differences in the inter-particle distances. While the NPs in the TS samples show a more open, cluster-like structure with small pore-like spaces up to 100 nm, the TPS samples always exhibit very densely packed

Comparative study of post-growth annealing of Cu(hfac)₂, Co₂(CO)₈ and Me₂Au(acac) metal precursors deposited by FEBID

• Marcos V. Puydinger dos Santos,
• Aleksandra Szkudlarek,
• Artur Rydosz,
• Carlos Guerra-Nuñez,
• Fanny Béron,
• Kleber R. Pirota,
• Stanislav Moshkalev,
• José Alexandre Diniz and
• Ivo Utke

Beilstein J. Nanotechnol. 2018, 9, 91–101, doi:10.3762/bjnano.9.11

• cluster size remains around 13 nm for all deposits: 12 nm, 13 nm and 14 nm for Co–C, Cu–C and Au–C deposits, respectively. Moreover, differences between the FEBID materials were observed with respect to the graphitisation process. Catalytic graphitisation using transition metals has been reported in

Transition from silicene monolayer to thin Si films on Ag(111): comparison between experimental data and Monte Carlo simulation

• Alberto Curcella,
• Romain Bernard,
• Yves Borensztein,
• Silvia Pandolfi and
• Geoffroy Prévot

Beilstein J. Nanotechnol. 2018, 9, 48–56, doi:10.3762/bjnano.9.7

• Reference ANR-11-IDEX-0004-02 and more specifically within the framework of the Cluster of Excellence MATISSE. We are grateful to Hervé Cruguel and Sébastien Royer for their technical support.

Dry adhesives from carbon nanofibers grown in an open ethanol flame

• Christian Lutz,
• Julia Syurik,
• C. N. Shyam Kumar,
• Christian Kübel,
• Michael Bruns and
• Hendrik Hölscher

Beilstein J. Nanotechnol. 2017, 8, 2719–2728, doi:10.3762/bjnano.8.271

• photoelectron peaks of metallic Cu, Ag, and Au. Sample cleaning to remove organic contaminations was performed with the Thermo Scientific MAGCIS (Mono Atomic and Gas Cluster Ion Source) using Ar1000+ clusters at 8 keV primary energy and a raster size of 2 × 4 mm2. The adhesion force and energy were determined

One-step chemical vapor deposition synthesis and supercapacitor performance of nitrogen-doped porous carbon–carbon nanotube hybrids

• Egor V. Lobiak,
• Lyubov G. Bulusheva,
• Ekaterina O. Fedorovskaya,
• Yury V. Shubin,
• Pavel E. Plyusnin,
• Pierre Lonchambon,
• Boris V. Senkovskiy,
• Zinfer R. Ismagilov,
• Emmanuel Flahaut and
• Alexander V. Okotrub

Beilstein J. Nanotechnol. 2017, 8, 2669–2679, doi:10.3762/bjnano.8.267

• ]. With the purpose to study the effect of the nature of the transition metal on the nitrogen content and the structure of the porous carbon–MWCNT hybrid, we used cluster-type polyoxomolybdates of Co, Ni, and Fe as catalyst precursors. In earlier work, we have shown that the thermal decomposition of such

• products of {Ni4Mo12}, {Co4Mo12}, and {Fe30Mo72} cluster compounds in air have revealed the presence of the phases NiMoO4 and CoMoO4 [22] as well as Fe2(Mo4)3 [29]. The reduction of these oxides in a CH4/H2 flow at 900 °C yields bimetallic particles as has been shown in our previous investigation [22

• carbon [2]. Conclusion Nitrogen-doped porous carbon/MWCNT hybrid materials were synthesized using cluster molecules containing molybdenum and transition metal as a source of catalytic nanoparticles for the CCVD synthesis. The cluster molecules were distributed over a MgO support before oxidation in air

Exploring wear at the nanoscale with circular mode atomic force microscopy

• Olivier Noel,
• Aleksandar Vencl and
• Pierre-Emmanuel Mazeran

Beilstein J. Nanotechnol. 2017, 8, 2662–2668, doi:10.3762/bjnano.8.266

• atoms of copper per micrometer of sliding have been removed. Then an atom-by-atom or atomic cluster by atomic cluster or nanograin-by-nanograin removal process may be involved in the wear mechanism. However, SEM imaging was of satisfactory resolution to precisely distinguish the morphology of the wear

Synthesis of [{AgO₂CCH₂OMe(PPh₃)}_n] and theoretical study of its use in focused electron beam induced deposition

• Jelena Tamuliene,
• Julian Noll,
• Peter Frenzel,
• Tobias Rüffer,
• Alexander Jakob,
• Bernhard Walfort and
• Heinrich Lang

Beilstein J. Nanotechnol. 2017, 8, 2615–2624, doi:10.3762/bjnano.8.262

• fragments from dissociation of [AgCH2OMe]. Supporting Information Supporting Information File 220: Additional figures and tables. Acknowledgements This work was conducted within the framework of the COST Action CM1301 (CELINA) and within the Federal Cluster of Excellence EXC 1075 MERGE Technologies for

Localized growth of carbon nanotubes via lithographic fabrication of metallic deposits

• Fan Tu,
• Martin Drost,
• Imre Szenti,
• Janos Kiss,
• Zoltan Kónya and
• Hubertus Marbach

Beilstein J. Nanotechnol. 2017, 8, 2592–2605, doi:10.3762/bjnano.8.260

• -Nürnberg) for fruitful discussions. This work has been supported by the research unit FOR1878/funCOS, the DFG through grant MA 4246/1-2, project D7 of the Excellence Cluster “Engineering of Advanced Materials” granted to the FAU Erlangen-Nürnberg. Financial support of this work by the National Research

Interactions of low-energy electrons with the FEBID precursor chromium hexacarbonyl (Cr(CO)₆)

• Jusuf M. Khreis,
• João Ameixa,
• Filipe Ferreira da Silva and
• Stephan Denifl

Beilstein J. Nanotechnol. 2017, 8, 2583–2590, doi:10.3762/bjnano.8.258

• to electron attachment under isolated conditions were observed. The ion yield curves (ion yield plotted as a function of the initial electron energy) for the formation of cluster anions containing two or more iron atoms turned out to be different from those of Fe(CO)5 in the gas phase. The dimer

• metal cation W2+ resulting from electron ionization of the neutral W(CO)6 dimer was reported by Neustetter et al. [23] showing the fast conversion of the weak cluster bond into a strong covalent metallic bond. In comparison to electron collisions, anisotropic coulombic explosion of CO ligands upon

Refractive index sensing and surface-enhanced Raman spectroscopy using silver–gold layered bimetallic plasmonic crystals

• Somi Kang,
• Sean E. Lehman,
• Matthew V. Schulmerich,
• An-Phong Le,
• Tae-woo Lee,
• Stephen K. Gray,
• Rohit Bhargava and
• Ralph G. Nuzzo

Beilstein J. Nanotechnol. 2017, 8, 2492–2503, doi:10.3762/bjnano.8.249

• Facility; and the Laser and Spectroscopy Facility. We also acknowledge the use of the Turing cluster, maintained and operated by the Computational Science and Engineering Program at the University of Illinois. The bulk of the work presented here in modified form was originally from the doctoral

Fabrication of CeO₂–MO_x (M = Cu, Co, Ni) composite yolk–shell nanospheres with enhanced catalytic properties for CO oxidation

• Ling Liu,
• Jingjing Shi,
• Hongxia Cao,
• Ruiyu Wang and
• Ziwu Liu

Beilstein J. Nanotechnol. 2017, 8, 2425–2437, doi:10.3762/bjnano.8.241

• dispersed transition-metal oxide cluster species. Information about crystallinity and phases of the samples were obtained from X-ray diffraction (XRD) analysis. Figure 6a displays the XRD patterns of the as-synthesized CeO2–MOx nanospheres. All diffraction peaks can be assigned to the fluorite-like cubic

• and CeO2. In addition, the pure Co3O4 bulk gets reduced at a high temperature of above 280 °C in the literature [6][11]. For the H2-TPR profile of CeO2–NiO sample, a sharp peak is clearly observed at around 250 °C, which can be due to the reduction of NiO cluster species weakly interacting with CeO2

Robust procedure for creating and characterizing the atomic structure of scanning tunneling microscope tips

• Sumit Tewari,
• Koen M. Bastiaans,
• Milan P. Allan and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2017, 8, 2389–2395, doi:10.3762/bjnano.8.238

• sample, the number of consecutively repeating traces was much larger. The lower number of repeating conductance traces may be attributed to the fact that our tip is not purely Au, but PtIr covered with Au. In the experiments of Andres et al. [29] with a graphene surface covered with a small cluster of Au

Electron beam induced deposition of silacyclohexane and dichlorosilacyclohexane: the role of dissociative ionization and dissociative electron attachment in the deposition process

• Ragesh Kumar T P,
• Sangeetha Hari,
• Krishna K Damodaran,
• Oddur Ingólfsson and
• Cornelis W. Hagen

Beilstein J. Nanotechnol. 2017, 8, 2376–2388, doi:10.3762/bjnano.8.237

• heteroleptic precursor [21][24][25][26] and on large heteronuclear carbonyl cluster compounds [22][23][30] that have partly proven to perform well in the FEBID deposition of magnetic alloys [31]. In fact, both DEA and DI cross sections of typical metal-containing FEBID precursors can be very high [32][33]. The

Au₅₅, a stable glassy cluster: results of ab initio calculations

• Dieter Vollath,
• David Holec and
• Franz Dieter Fischer

Beilstein J. Nanotechnol. 2017, 8, 2221–2229, doi:10.3762/bjnano.8.222

• .8.222 Abstract Structure and properties of small nanoparticles are still under discussion. Moreover, some thermodynamic properties and the structural behavior still remain partially unknown. One of the best investigated nanoparticles is the Au55 cluster, which has been analyzed experimentally and

• theoretically. However, up to now, the results of these studies are still inconsistent. Consequently, we have carried out the present ab initio study of the Au55 cluster, using up-to-date computational concepts, in order to clarify these issues. Our calculations have confirmed the experimental result that the

• thermodynamically most stable structure is not crystalline, but it is glassy. The non-crystalline structure of this cluster was validated by comparison of the coordination numbers with those of a crystalline cluster. It was found that, in contrast to bulk materials, glass formation is connected to an energy release

Suppression of low-energy dissociative electron attachment in Fe(CO)₅ upon clustering

• Jozef Lengyel,
• Peter Papp,
• Štefan Matejčík,
• Jaroslav Kočišek,
• Michal Fárník and
• Juraj Fedor

Beilstein J. Nanotechnol. 2017, 8, 2200–2207, doi:10.3762/bjnano.8.219

• using two complementary cluster-beam setups. We have identified two mechanisms that lead to synthesis of complex anions with mixed Fe/CO composition. These two mechanisms are operative in distinct electron energy ranges. It is shown that the elementary decomposition mechanism that has received perhaps

• (crossed electron – target beam with product mass analysis) and enable direct comparisons for various aggregation degrees (gas phase – small clusters – large clusters). When compared to the surface-based ion desorption approach, cluster-beam experiments do not suffer from desorption probability problem

• . Once a fragment ion is created, it can be detected via mass spectrometry, regardless of whether it separated from the rest of the cluster (”desorption”) or stayed attached to the rest of the cluster (”no desorption”). Our recent experiments [14] on precursor molecules adsorbed on large argon

A comparative study of the nanoscale and macroscale tribological attributes of alumina and stainless steel surfaces immersed in aqueous suspensions of positively or negatively charged nanodiamonds

• Colin K. Curtis,
• Antonin Marek,
• Alex I. Smirnov and
• Jacqueline Krim

Beilstein J. Nanotechnol. 2017, 8, 2045–2059, doi:10.3762/bjnano.8.205

• NDs or physisorbed adsorbates, neither of which would be readily observed by AFM. In order to convert the frequency shifts to particle density on the surface, we assume a cluster size of 25 nm and a packing fraction within the cluster of 0.7. The mass of each cluster would be [(25 nm/5 nm)3] × 0.7

Advances and challenges in the field of plasma polymer nanoparticles

• Andrei Choukourov,
• Pavel Pleskunov,
• Daniil Nikitin,
• Valerii Titov,
• Artem Shelemin,
• Mykhailo Vaidulych,
• Anna Kuzminova,
• Pavel Solař,
• Jan Hanuš,
• Jaroslav Kousal,
• Ondřej Kylián,
• Danka Slavínská and
• Hynek Biederman

Beilstein J. Nanotechnol. 2017, 8, 2002–2014, doi:10.3762/bjnano.8.200

• Holešovičkách 2, 180 00 Prague, Czech Republic G. A. Krestov Institute of Solution Chemistry of the Russian Academy of Sciences, Akademicheskaya 1, 153045 Ivanovo, Russia 10.3762/bjnano.8.200 Abstract This contribution reviews plasma polymer nanoparticles produced by gas aggregation cluster sources either via

• focus on the development of novel nanostructured surfaces. Keywords: gas aggregation cluster source; nanocomposite; nanoparticles; plasma polymer; sputtering; Review Historical background “A macromolecule is a molecule of high relative molecular mass, the structure of which essentially comprises the

• can be used as biomolecule and drug carriers [38][39][40]. Gas aggregation cluster sources (GAS) were considered feasible for the synthesis of plasma polymer NPs with a tuneable size distribution, retention of functional groups and cross-link density. The concept of GAS was originally developed for

Bi-layer sandwich film for antibacterial catheters

• Gerhard Franz,
• Florian Schamberger,
• Hamideh Heidari Zare,
• Sara Felicitas Bröskamp and
• Dieter Jocham

Beilstein J. Nanotechnol. 2017, 8, 1982–2001, doi:10.3762/bjnano.8.199

• [24]. Colloidal silver can be prepared by electrolytical or chemical reduction of a silver salt solution and consists of positively charged silver clusters exhibiting a diameter of typically between 5 and 15 nm and, containing approx. 103 to 109 atoms/cluster. From the generation process, it is

• evident that the clusters mainly consist of atoms, the residual ions are responsible for keeping the clusters apart, thereby suppressing the aggregation to larger units. The ions fight the bacteria in a multifold manner and are evidently replenished from the cluster after having reacted. Finally, toxicity

Intercalation of Si between MoS₂ layers

• Rik van Bremen,
• Qirong Yao,
• Soumya Banerjee,
• Deniz Cakir,
• Nuri Oncel and
• Harold J. W. Zandvliet

Beilstein J. Nanotechnol. 2017, 8, 1952–1960, doi:10.3762/bjnano.8.196

• , which in total are comprised of 3500 spectra, are displayed in Figure 2. The I(V) spectra are almost identical to each other. The small difference between both curves might be a residual effect of Si residing underneath the MoS2 layer. If the top layer were a silicon cluster the I(V) spectra would

• 3.52 Å. In order to study the possible formation of silicene between the MoS2 monolayers, we consider a buckled 2D silicon cluster (Si37) consisting of six-membered silicon rings. We used a 7 × 7 super-cell structure for the MoS2 bilayer. Initial and equilibrium geometries for both a free-standing as

• well as the intercalated silicon cluster inserted between the MoS2 layers are shown in Figure 7. We found that a free-standing 2D buckled silicon cluster is, in contrast to an infinite silicene layer, not even metastable in vacuum and spontaneously transforms into a strongly buckled 3D assembly as seen