Low-energy electron interaction and focused electron beam-induced deposition of molybdenum hexacarbonyl (Mo(CO)₆)

• Po-Yuan Shih,
• Maicol Cipriani,
• Christian Felix Hermanns,
• Jens Oster,
• Klaus Edinger,
• Armin Gölzhäuser and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2022, 13, 182–191, doi:10.3762/bjnano.13.13

• , University of Iceland, Dunhagi 3, 107 Reykjavik, Iceland 10.3762/bjnano.13.13 Abstract Motivated by the potential role of molybdenum in semiconductor materials, we present a combined theoretical and experimental gas-phase study on dissociative electron attachment (DEA) and dissociative ionization (DI) of Mo

• electron transmission study. Relative contributions of individual ionic species obtained through DEA and DI of Mo(CO)6 and the average CO loss per incident are calculated and compared to the composition of the FEBID deposits produced. These are also compared to gas phase, surface science and deposition

• deposits composition with carbonyl loss through DEA vs DI. We compare this to previous gas phase, surface science and FEBID experiments on W(CO)6 and discuss these studies in context to the current findings and potential deposition mechanisms. Method Quantum chemical calculations Similar to the approach in

Sputtering onto liquids: a critical review

• Anastasiya Sergievskaya,
• Adrien Chauvin and
• Stephanos Konstantinidis

Beilstein J. Nanotechnol. 2022, 13, 10–53, doi:10.3762/bjnano.13.2

• as gas-phase scattering is minimized. The film deposition rate, lying typically in the range of several nanometers per minute, is therefore higher compared to non-magnetized sputtering discharges. Here a remark should be made: While the film growth rate is usually expressed in units of thickness per

• gas phase and subsequent film growth can be computed using, for example, SIMTRA [37] and NASCAM [38] codes, respectively. The evolution of the sputtering yield calculated by SRIM for carbon (C), titanium (Ti), and Au targets as a function of the kinetic energy of the bombarding argon ions is presented

• and lose their energy before reaching the neighboring surfaces onto which they condense. The collision rate and the fraction of the kinetic energy they dissipate in the gas phase mainly depend on the product of pressure times the distance traveled. Typically, the pressure lies in the range of pascals

Chemical vapor deposition of germanium-rich CrGe_x nanowires

• Vladislav Dřínek,
• Stanislav Tiagulskyi,
• Roman Yatskiv,
• Jan Grym,
• Radek Fajgar,
• Věra Jandová,
• Martin Koštejn and
• Jaroslav Kupčík

Beilstein J. Nanotechnol. 2021, 12, 1365–1371, doi:10.3762/bjnano.12.100

• in mind that the melting point of nanodroplets may be reduced by hundreds of kelvins [19]. Tapering of the CrGex coating is observed during the whole experiment as Cr and Ge atoms migrate from the NW bottom and/or are transferred directly from the gas phase [20]. Several attempts were made to

Identifying diverse metal oxide nanomaterials with lethal effects on embryonic zebrafish using machine learning

• Richard Liam Marchese Robinson,
• Haralambos Sarimveis,
• Philip Doganis,
• Xiaodong Jia,
• Marianna Kotzabasaki,
• Christiana Gousiadou,
• Stacey Lynn Harper and
• Terry Wilkins

Beilstein J. Nanotechnol. 2021, 12, 1297–1325, doi:10.3762/bjnano.12.97

• ].) Here, molecular descriptors were calculated for the gas phase, neutral forms of the molecular constituents of the surface components. (This approach is similar to previous modelling studies of NBI Knowledgebase data, where, in addition to exploring the identities of the surface functional groups as

• variables related to biological effects, surface chemical composition was encoded using molecular descriptors computed for the gas phase molecules [28][29], with pH value-dependent ionization state reported to have been taken into account in one study [29].) In reality, these molecules are likely to be

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

• loss spectra for Pt(PF3)4 molecules in the gas phase were measured experimentally and compared with time-dependent DFT (TDDFT) calculations in [26]. In the simulations presented below two values of the energy deposited into the molecule, namely 205 kcal/mol (8.9 eV) and 300 kcal/mol (13 eV) were

Criteria ruling particle agglomeration

• Dieter Vollath

Beilstein J. Nanotechnol. 2021, 12, 1093–1100, doi:10.3762/bjnano.12.81

• . Synthesis of larger particles may be carried out in the gas phase, where the probability of collision is controlled by the geometry of the particles or forces among the particles [1]. Alternatively, in case of existing particles, the agglomeration is controlled by the minimum of free enthalpy. In this case

Prediction of Co and Ru nanocluster morphology on 2D MoS₂ from interaction energies

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2021, 12, 704–724, doi:10.3762/bjnano.12.56

• determined experimentally. To understand the binding of Co and Ru to the MoS2 monolayer, four different energies are computed: 1. Binding energy per metal atom: Etotal is the total energy of the relaxed Con or Run (n = 1–4) adsorbed on MoS2. The energy of a single gas-phase metal atom (Emetal_atom) is

The preparation temperature influences the physicochemical nature and activity of nanoceria

• Robert A. Yokel,
• Wendel Wohlleben,
• Johannes Georg Keller,
• Matthew L. Hancock,
• Jason M. Unrine,
• D. Allan Butterfield and
• Eric A. Grulke

Beilstein J. Nanotechnol. 2021, 12, 525–540, doi:10.3762/bjnano.12.43

• from a liquid or gas phase. If NM-212 was exposed to a high temperature it would be expected to have less surface Ce3+ [58], which is the case (Supporting Information File 1, Table S1), and show slow dissolution, as was seen with NM-212 and the calcined solvothermally synthesized nanoceria. The cerium

Gold(I) N-heterocyclic carbene precursors for focused electron beam-induced deposition

• Cristiano Glessi,
• Aya Mahgoub,
• Cornelis W. Hagen and
• Mats Tilset

Beilstein J. Nanotechnol. 2021, 12, 257–269, doi:10.3762/bjnano.12.21

• properties of a FEBID precursor molecule are crucial for the deposition process. The precursor molecule should be volatile in a suitable range of pressures and temperatures. Under these conditions, it needs to be easily deliverable in the gas phase, adsorb on a substrate, be sensitive to the electron beam

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

• W3O9. To stabilize and utilize different charge states of the cluster outside the gas phase, we have prepared a substrate material, which, on the one hand, offers a sufficient template effect for the self-organization of the nanoclusters and, on the other hand, exhibits a rather low electronic surface

• titanium oxide layer due to the formed W3O9 interlayer. In consequence, this only indirect bonding to the surface leads to an electronic state, which should be very near to that of an isolated molecule in the gas phase. Indeed, our experiments with the STM tip exhibited a behavior that had never been

• atoms remain in the oxidation state +VI and one is reduced to +IV (compare Figure 3c and Figure 3d). The latter one has less unoccupied electronic states and, therefore, is not resolved by scanning with a positive bias voltage. Our DFT calculations of W3O9 and of a hypothetical W3O8 molecule in the gas

A review on the green and sustainable synthesis of silver nanoparticles and one-dimensional silver nanostructures

• Sina Kaabipour and
• Shohreh Hemmati

Beilstein J. Nanotechnol. 2021, 12, 102–136, doi:10.3762/bjnano.12.9

• chamber where the metal of interest is vaporized into a low-density gas phase, becomes supersaturated by decreasing temperature, and then is condensed to form nuclei which then grow into nanoparticles [113][137]. The chamber gas usually contains an inert gas such as helium or argon [113][224]. AgNPs

• the gas phase to the reactor chamber. Second, adsorption of the vapor on the substrate surface and establishment of medium compounds followed by formation of a layer. Third, nucleation and growth of the layer through heating [241]. The important factors that control the process and size of synthesized

The role of gold atom concentration in the formation of Cu–Au nanoparticles from the gas phase

• Yuri Ya. Gafner,
• Svetlana L. Gafner,
• Darya A. Ryzkova and
• Andrey V. Nomoev

Beilstein J. Nanotechnol. 2021, 12, 72–81, doi:10.3762/bjnano.12.6

• using computer simulation methods of only one of the physical methods used for the production of binary Cu–Au nanoparticles (i.e, the synthesis from a high-temperature gas phase). For the first time, a detailed study of the dependence of the atomic ordering of Cu–Au particles on the concentration of

• and internal structure, and the main mechanisms involved in the formation of binary Cu–Au nanoparticles upon deposition from a gaseous medium. Computer Model Synthesis from the gas phase is one of the main physical methods used for producing nanopowders. However, since particle formation reactions

• formation of Cu–Au nanoparticles under conditions that are similar to the process of a real synthesis by the condensation of the gas phase. In our model, all the atoms were randomly distributed in a simple cubic lattice, with an average distance of 30 Bohr radii between them. This was done in order to

Atomic layer deposited films of Al₂O₃ on fluorine-doped tin oxide electrodes: stability and barrier properties

• Hana Krýsová,
• Michael Neumann-Spallart,
• Hana Tarábková,
• Pavel Janda,
• Ladislav Kavan and
• Josef Krýsa

Beilstein J. Nanotechnol. 2021, 12, 24–34, doi:10.3762/bjnano.12.2

• the topic of the present work, in which atomic layer deposition (ALD) is used as the coating technique [1]. This method is a gas-phase process which relies on a molecular approach. Therefore, a conformal coating, which reaches the pores and crevasses of the sample, can be obtained. Protective coating

The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• excited electron from the LUMO into unoccupied metallic states and/or a filling of the HOMO by an electron from the metal. We note that the HOMO and LUMO for the chemisorbed molecule differ from those of the gas phase molecule. Thus, the LUMO that is drawn in Figure 1a is not identical to the LUMO in the

• gas phase. For a second molecular layer, even without significant overlap of the wave functions of metal and molecule, quenching is also possible, because the CT may occur from the second layer to the metal via states in the first layer [5]. In principle, the hybridization of molecular and metallic

• differential energies of the PTCDA orbitals remain unaltered in comparison to those of PTCDA in the gas phase, which points to a more physisorptive bonding to the hBN/Cu(111) surface [32]. The HOMO of PTCDA is found at ca. 2.6 eV [32]. Hence, we can expect that both the LUMO and the HOMO are placed within the

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1615–1622, doi:10.3762/bjnano.11.144

• view of the optimum adsorption geometry, including isosurfaces at ±0.01 e/Å3 of the electron density difference Δρ = ρfull − ρslab − ρPTCDA. This difference was calculated as a difference between the electron densities of the full (ρfull), CaF2 slab (ρslab), and PTCDA gas phase (ρPTCDA) systems. The

• well as the three lowest unoccupied molecular orbitals (LUMO, LUMO+1, and LUMO+2) as calculated with cp2k for the PTCDA/CaF2(111) system are depicted in Figure 4e–h. The orbital shapes largely resemble earlier calculations of a flat PTCDA molecule in the gas phase [10], although the LUMO+1 and LUMO+2

• states are here separated by about 0.1 eV and found in different order (in agreement with a previous study [10], a smaller LUMO+1/LUMO+2 energetic separation was calculated for the gas-phase molecule). The dominant contribution of the orbitals to the data shown in Figure 2 is deferred from the orbital

Adsorption and self-assembly of porphyrins on ultrathin CoO films on Ir(100)

• Feifei Xiang,
• Tobias Schmitt,
• Marco Raschmann and
• M. Alexander Schneider

Beilstein J. Nanotechnol. 2020, 11, 1516–1524, doi:10.3762/bjnano.11.134

• superstructure with respect to the quasi-hexagonal structure of the CoO 2BL film (red rectangle in Figure 6b). Arranging 2 in its gas phase configuration within this cell, we find that the CN groups of the dipolar bond have a distance of 0.4 nm and that the hydrogen bond has a length of 0.3 nm between the N atom

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• to 5A, 6P is geometrically more flexible, more specifically, it is nonplanar in the gas phase and has a relatively low electron affinity. On the pristine Ag(100) substrate, 6P simply physisorbs with no evidence of LUMO hybridization, which remains unoccupied [21]. It will be shown that the

• . In the gas phase, 6P naturally occurs with a torsional angle of 35° between its phenyl rings [26]. The observation of such a twist on MgO(100)/Ag(100) suggests that the interaction between the 6P molecules and MgO is very weak. In addition, next to the 6P molecules with a zig-zag appearance, there

• overlap between the phenyl rings. This will cause an increase in the energy spread of the π bands, resulting in a decrease in the ionization potential and an increase in the electron affinity. Gas phase DFT calculations show that the EA of planar 6P (1.74 eV) is indeed 0.3 eV higher than the EA of twisted

Self-assembly and spectroscopic fingerprints of photoactive pyrenyl tectons on hBN/Cu(111)

• Domenik M. Zimmermann,
• Knud Seufert,
• Luka Ðorđević,
• Tobias Hoh,
• Sushobhan Joshi,
• Tomas Marangoni,
• Davide Bonifazi and
• Willi Auwärter

Beilstein J. Nanotechnol. 2020, 11, 1470–1483, doi:10.3762/bjnano.11.130

• at the submolecular level via STM and STS, e.g., reveal to be close to the gas-phase-like frontier orbitals. The electronic landscape of the hBN/Cu(111) template induces a periodic modulation of the electronic structure of the pyrene films at the single digit nanometer scale. The on-surface STM/STS

• , elongated protrusion, four additional lobes contributed to the X-shaped appearance of the molecular units of 1. Each of these peripheral protrusions was attributed to one pyridin-4-ylethynyl substituent. Atomistic models (see overlays in Figure 2b), reflecting the gas-phase optimized molecular structure

• . Furthermore, the agreement between the gas-phase calculations and STM data indicated that no charging occurred upon pyrene adsorption on hBN/Cu(111) [37]. To complement the on-surface investigations, we measured the optical gap by means of UV–vis spectroscopic characterization in solution (toluene) of the

Protruding hydrogen atoms as markers for the molecular orientation of a metallocene

• Linda Laflör,
• Michael Reichling and
• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1432–1438, doi:10.3762/bjnano.11.127

• ferrocene, the rotational barrier between these conformers amounts to only 0.04 eV in the gas phase [11][12][13], while for substituted ferrocenes the energy barrier values determined in the gas phase amount up to 0.2 eV [14][15][16]. In solution, barrier values of up to 0.7 eV are measured [17][18] and for

One-step synthesis of carbon-supported electrocatalysts

• Sebastian Tigges,
• Nicolas Wöhrl,
• Ivan Radev,
• Ulrich Hagemann,
• Markus Heidelmann,
• Thai Binh Nguyen,
• Stanislav Gorelkov,
• Stephan Schulz and
• Axel Lorke

Beilstein J. Nanotechnol. 2020, 11, 1419–1431, doi:10.3762/bjnano.11.126

• the growth of the Pt-NPs does not occur in the gas phase but on the surface of the CNWs since nanoparticle growth in the gas phase should result in smaller particle sizes at high gas velocities (thus shorter residence time of the NP in the plasma), which is not the case here. Besides, the degree of

• precursor dissociation and hence the platinum concentration in the gas phase is expected to decrease with increasing gas velocities, as was previously demonstrated [17]. Electrochemically active surface area and long-term stability Even though the influence of the physicochemical properties of Pt/C on its

Analysis of catalyst surface wetting: the early stage of epitaxial germanium nanowire growth

• Owen C. Ernst,
• Felix Lange,
• David Uebel,
• Thomas Teubner and
• Torsten Boeck

Beilstein J. Nanotechnol. 2020, 11, 1371–1380, doi:10.3762/bjnano.11.121

• ripening requires the existence of a medium where the material can be transported. Since there is no wetting layer (according to the WA and EA models, Figure 1), the Laplace pressure cannot be relieved by Ostwald ripening. Nevertheless, an Ostwald ripening process could also take place through the gas

• phase, although this process is kinetically inhibited. The re-evaporation process leads to a decrease in the number of droplets per area, while the droplet diameter values remain constant and the diameter distribution remains Gaussian, and no LSW distribution occurs as in Ostwald ripening processes [25

Impact of fluorination on interface energetics and growth of pentacene on Ag(111)

• Qi Wang,
• Meng-Ting Chen,
• Antoni Franco-Cañellas,
• Bin Shen,
• Thomas Geiger,
• Holger F. Bettinger,
• Frank Schreiber,
• Ingo Salzmann,
• Alexander Gerlach and
• Steffen Duhm

Beilstein J. Nanotechnol. 2020, 11, 1361–1370, doi:10.3762/bjnano.11.120

• ][30][31][32][33][34][35]. PEN and PFP have almost identical optical gaps in thin films (1.85 eV and 1.75 eV, respectively) [36][37], and the experimental gas phase IEs (measured by UPS) are 6.59 eV [38] and 7.50 eV [39], respectively. This trend of the IEs is also found for thin films comprised of PEN

• signs for PEN and PFP [11]. Electrostatic potential maps of PEN, F4PEN and PFP in the gas phase can be found in [46]. In general, hydrogen atoms bear a minimum, and fluorine atoms a maximum of the electron density, i.e., the quadrupole moments of F4PEN along the molecular short and long axes have

3D superconducting hollow nanowires with tailored diameters grown by focused He⁺ beam direct writing

• Rosa Córdoba,
• Alfonso Ibarra,
• Dominique Mailly,
• Isabel Guillamón,
• Hermann Suderow and
• José María De Teresa

Beilstein J. Nanotechnol. 2020, 11, 1198–1206, doi:10.3762/bjnano.11.104

• advantage of its small beam diameter (approx. 0.3 nm) and low proximity effect [28]. When precursor molecules from the gas phase are adsorbed on a substrate surface, He+ FIB dissociates them into non-volatile and volatile products. The non-volatile products attach to the surface, resulting in a deposit

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• surfaces was motivated as follows. C42H28 is a polycyclic aromatic hydrocarbon (Figure 1a) with an extended system of delocalized π electrons. In the gas phase, intramolecular steric hindrance [11][12] causes the phenyl groups to rotate around their σ bonds, out of the tetracene backbone plane (Figure 1b

Revealing the local crystallinity of single silicon core–shell nanowires using tip-enhanced Raman spectroscopy

• Marius van den Berg,
• Ardeshir Moeinian,
• Arne Kobald,
• Yu-Ting Chen,
• Anke Horneber,
• Steffen Strehle,
• Alfred J. Meixner and
• Dai Zhang

Beilstein J. Nanotechnol. 2020, 11, 1147–1156, doi:10.3762/bjnano.11.99

• electronic functionality of such nanometer-scale building blocks. A rational and well-established synthesis strategy for the creation of complex silicon nanostructures is metal-catalyzed vapor–liquid–solid (VLS) nanowire growth [13]. VLS nanowire growth belongs to the gas-phase synthesis procedures, similar