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

•  1), dissociative ionization (DI; Equation 2), neutral dissociation (ND; Equation 3) and dipolar dissociation (DD; Equation 4) [13][14][15][16][17][18][19][20]. The respective reaction schemes for each of these pathways are: The double dagger (‡) signifies vibrational or electronic excitation, the

• same is true for electronic excitation upon electron impact [34]. However, no experimental information is available on actual cross sections for neutral dissociation upon such electronic excitations. This is due to the difficulties associated with the detection of the resulting neutral species and

• that the inert behaviour of SCH towards DEA, as compared to DCSCH, only concerns electrons of energies below 2 eV and in the range of 6–9 eV. The effective dissociation yield of DEA in the DCSCH EBID process, however, depends not only on the DEA cross sections, but also on the available number of

Dissociative electron attachment to coordination complexes of chromium: chromium(0) hexacarbonyl and benzene-chromium(0) tricarbonyl

• Janina Kopyra,
• Paulina Maciejewska and
• Jelena Maljković

Beilstein J. Nanotechnol. 2017, 8, 2257–2263, doi:10.3762/bjnano.8.225

• fabricate three-dimensional metal-containing nanoscale structures [4][5]. FEBID is a direct-write technique in which a highly focused, high-energy electron beam impinges on precursor molecules physisorbed onto a substrate, thereby causing their dissociation, and in the ideal case, leading to pure deposit

• molecules via various decomposition processes such as dissociative ionization (DI), dipolar dissociation (DD), neutral dissociation (ND), and dissociative electron attachment (DEA) [8]. These reactions occur with relatively high cross sections and typically result in partial fragmentation of the precursor

• known that DEA is responsible for the dissociation of the molecule. The DEA reaction is a two-step process in which, in a first step, an incident electron is captured by the target molecule to form a transient negative ion (TNI). Since the TNI is not stable, it will decay in a second step either via

Comprehensive investigation of the electronic excitation of W(CO)₆ by photoabsorption and theoretical analysis in the energy region from 3.9 to 10.8 eV

• Mónica Mendes,
• Khrystyna Regeta,
• Filipe Ferreira da Silva,
• Nykola C. Jones,
• Søren Vrønning Hoffmann,
• Gustavo García,
• Chantal Daniel and
• Paulo Limão-Vieira

Beilstein J. Nanotechnol. 2017, 8, 2208–2218, doi:10.3762/bjnano.8.220

• of relevance to estimate neutral dissociation cross sections of W(CO)6, a precursor molecule in focused electron beam induced deposition (FEBID) processes, from electron scattering measurements. Keywords: cross sections; density functional theory (DFT) calculations; focused electron beam induced

• beam impinging on the surface where dissociative electron attachment (DEA) processes are relevant, although at those energies electron impact excitations yielding neutral dissociation are prevalent in detriment to DEA [25]. Gas-phase DEA studies in the electron energy range from 0 to 14 eV reported by

• Wnorowski et al. [26] revealed the strong dissociation character of W(CO)6, with no formation of bare W− metal anions. Negative ion states of transition-metal hexacarbonyls have been obtained by electron transmission spectroscopy (ETS) with W(CO)6 attachment energies of 1.53, 2.46 and 4.26 eV [27]. We note

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

• a large change (increase) in the DEA cross section, since this is extremely sensitive to the overlap of the two curves around the Franck–Condon region [11]. Finally, the target molecule can be stabilized by mechanical suppression of the dissociation (caging) and energy transfer to the environment

• undergoes neutral dissociation. This yields an electron with very low residual energy that causes DEA in another precursor molecule and the resulting anion effectively reacts with the coordinatively unsaturated products of the neutral dissociation. Such a process – possibly very relevant at realistic FEBID

• , which is very fragmentative in the gas phase, becomes much less destructive in clusters, since the ligands are stabilized by caging. The electronic excitation and subsequent neutral dissociation (very effective in the gas phase [22][23]) manifests itself in clusters via self-scavenging as a synthesis

Angstrom-scale flatness using selective nanoscale etching

• Takashi Yatsui,
• Hiroshi Saito and
• Katsuyuki Nobusada

Beilstein J. Nanotechnol. 2017, 8, 2181–2185, doi:10.3762/bjnano.8.217

• continuous-wave diode-pumped solid-state (DPSS) laser (λ = 532 nm; 2.33 eV; excitation power: 119.4 W/cm2). Thus, the incident photon energy was lower than the dissociation energy of Cl2 (3.10 eV) [11] and the hypochlorous acid (3.35 eV) [12]; therefore, the Cl2 or hypochlorous acid dissociated on the

• protrusions only. In the solution, a light source with a photon energy of 4.66 eV (higher than the dissociation energy) dissociated the hypochlorous acid and consequently produced Cl radicals [13]. This process is expected to be similar to the etching of glass when Cl2 gas is used. The laser light was

Modelling focused electron beam induced deposition beyond Langmuir adsorption

• Dédalo Sanz-Hernández and
• Amalio Fernández-Pacheco

Beilstein J. Nanotechnol. 2017, 8, 2151–2161, doi:10.3762/bjnano.8.214

• fractional molecule coverage θ = N/N0 is given by [25]: The first, second and third terms on the right hand side of Equation 1 refer to (Langmuir) adsorption, thermal desorption and electron dissociation, respectively, where F (molec/m2s) is the precursor flux, s the surface sticking coefficient, N0 (molec

• /m2s) the density of available sites, ν0 (1/s) is the thermal desorption attempt frequency, E (J) is desorption energy, T (K) is the temperature, kB is Boltzmann’s constant, σ (m2) is the molecule dissociation cross section and J (1/m2s) is the electron flux density. No diffusion is considered, which

• before, the three right terms in Equation 2 and Equation 3 describe adsorption, desorption and dissociation effects, respectively, with prefactors as in Equation 1. However, now the fractional coverage of an area with i monolayers depends not only on that coverage, but also on areas covered by one more

α-Silicene as oxidation-resistant ultra-thin coating material

• Ali Kandemir,
• Fadil Iyikanat,
• Cihan Bacaksiz and
• Hasan Sahin

Beilstein J. Nanotechnol. 2017, 8, 1808–1814, doi:10.3762/bjnano.8.182

• dissociation of the oxygen molecule is favorable and requires ca. 300 meV to exceed the energy barrier of transition. Since the H1 hollow site is the most permeable site, the maximum value of the transition energy barrier converges to ca. 300 meV. Two possible configurations, in-S and top-S (Figure 4g,h), are

Fluorination of vertically aligned carbon nanotubes: from CF₄ plasma chemistry to surface functionalization

• Claudia Struzzi,
• Mattia Scardamaglia,
• Jean-François Colomer,
• Alberto Verdini,
• Luca Floreano,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2017, 8, 1723–1733, doi:10.3762/bjnano.8.173

• produced by electron-impact induced dissociation. In this framework, attention has been dedicated to the analysis of fluorine-based plasma chemical composition, and many diagnostic techniques have been used to understand the possible reactions occurring during pure CF4 discharge [2][3][4]. The study of the

Process-specific mechanisms of vertically oriented graphene growth in plasmas

• Subrata Ghosh,
• Shyamal R. Polaki,
• Niranjan Kumar,
• Sankarakumar Amirthapandian,
• Mohamed Kamruddin and
• Kostya (Ken) Ostrikov

Beilstein J. Nanotechnol. 2017, 8, 1658–1670, doi:10.3762/bjnano.8.166

• , CH, CH+, H, H+) through electron-impact dissociation of CH4 [26]. Electrons move faster than the ions, hence the surface acquires a distributed negative electric charge [57]. This negatively charged surface produces microscopic electric fields that accelerate the ions to achieve higher energies

• towards this are mainly surface adatom mobility, long-lived species, dissociation rate of gas(es) in the plasma, C/H ratios, and transport of the plasma species. The activation energy for the vertical growth is found to be 0.57 eV. The decreasing trend of residual compressive stress for vertical growth

Fixation mechanisms of nanoparticles on substrates by electron beam irradiation

• Daichi Morioka,
• Tomohiro Nose,
• Taiki Chikuta,
• Kazutaka Mitsuishi and
• Masayuki Shimojo

Beilstein J. Nanotechnol. 2017, 8, 1523–1529, doi:10.3762/bjnano.8.153

• also demonstrated. Figure 11 shows silica nanoparticles fixed on a Au-coated Si substrate. As the surface of colloidal silica particles was modified with –COOH groups, a dissociation of the organic shells occurs and the particles are fixed on the substrate. Conclusion The mechanism of fixing

Light-induced magnetoresistance in solution-processed planar hybrid devices measured under ambient conditions

• Sreetama Banerjee,
• Daniel Bülz,
• Danny Reuter,
• Karla Hiller,
• Dietrich R. T. Zahn and
• Georgeta Salvan

Beilstein J. Nanotechnol. 2017, 8, 1502–1507, doi:10.3762/bjnano.8.150

• thermally evaporated TIPS-pentacene OFETs in [9], which is an indication that the processing methods of the TIPS-pentacene do not influence the intrinsic mechanism of the OMAR in this organic semiconducting material. In the e–h model, the recombination into electrically neutral excitons and the dissociation

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• photogeneration in OSCs is mainly determined by the properties of the CTS. The dominant fraction of the CTS thermalizes [33] and only a small fraction might remain “hot” before dissociation [34][35] (d and d*, respectively) into free electrons and holes (charge separated state (CSS)). These separated charge

• dissociation will be uncompetitive compared to geminate recombination, leading to a lower photogeneration yield. The CTS can be in singlet and triplet configuration, although (due to the weak interaction within the polaron pair) energetically close. Therefore, the interconversion from singlet to triplet within

CVD transfer-free graphene for sensing applications

• Chiara Schiattarella,
• Sten Vollebregt,
• Tiziana Polichetti,
• Brigida Alfano,
• Ettore Massera,
• Maria Lucia Miglietta,
• Girolamo Di Francia and
• Pasqualina Maria Sarro

Beilstein J. Nanotechnol. 2017, 8, 1015–1022, doi:10.3762/bjnano.8.102

• Si technology, is of crucial importance [14][15]. A possible choice for the synthesis of large-area graphene is the metal-assisted hydrocarbon dissociation and/or the deposition method from solid carbon sources. In both cases, after the growth the graphene film needs to be transferred onto other

Needs and challenges for assessing the environmental impacts of engineered nanomaterials (ENMs)

• Michelle Romero-Franco,
• Hilary A. Godwin,
• Muhammad Bilal and
• Yoram Cohen

Beilstein J. Nanotechnol. 2017, 8, 989–1014, doi:10.3762/bjnano.8.101

• ENM properties such as agglomeration, reactivity/charge, critical functional groups, contaminant dissociation and size; evidence of toxicity; and other factors related to toxicity such as bioavailability and bioaccumulation). This outranking method has the advantage, when criteria metrics are not

• scale 1–100 based on literature review for the studied ENMs); agglomeration, reactivity/charge, critical functional groups and contaminant dissociation (qualitative scale of 1–5, where scores are assigned based on expert judgement with 1 representing the most favorable score as judged based on the

Investigation of growth dynamics of carbon nanotubes

• Marianna V. Kharlamova

Beilstein J. Nanotechnol. 2017, 8, 826–856, doi:10.3762/bjnano.8.85

• ][31][32]. There are three different steps in the VLS growth mechanism of carbon filaments and nanotubes. In the first step, atomic carbon is provided on the surface of a hot metallic particle by dissociation of adsorbed molecules. In the second step, carbon dissolves into the bulk of the catalyst

• steps, including the dissociation of gaseous carbon precursor on the surface of the catalytic particle, the surface diffusion of carbon atoms on the solid particle and the precipitation of carbon in the form of nanotubes. The similarity of the terms “VLS” and “VSS” and different types of the carbon

• growth of the nanotube continues as long as fresh feedstock is supplied, unless the catalyst particle becomes deactivated by an impermeable carbon shell. In the base-growth model, the initial precursor dissociation and carbon diffusion occur similarly to those in the tip-growth model, but the carbon

Surface improvement of organic photoresists using a near-field-dependent etching method

• Felix J. Brandenburg,
• Tomohiro Okamoto,
• Hiroshi Saito,
• Benjamin Leuschel,
• Olivier Soppera and
• Takashi Yatsui

Beilstein J. Nanotechnol. 2017, 8, 784–788, doi:10.3762/bjnano.8.81

• molecules can be dissociated at 5.12 eV [12], and these radical O atoms react with the surface of a specimen. However, it is important to keep in mind that the laser energy used is below 5.12 eV (242 nm) and therefore does not directly cause the dissociation. The etching laser wavelength (325 nm) is

• carefully chosen to be below the direct O2 dissociation energy. Previous theories suggest localized optical near-fields can cause two-step excitation via vibrational levels in molecules [13]. In theory, the localized optical near-field has a nonuniform field distribution and thus can activate the dipole

• are believed to be primarily present in the protrusions on the surface. Thus, O2 dissociation, and hence etching, occurs primarily at locations with a high protrusion density. Previous research suggests that near-field-based energy upconversion can also occur through multiphoton absorption instead of

Impact of air exposure and annealing on the chemical and electronic properties of the surface of SnO₂ nanolayers deposited by rheotaxial growth and vacuum oxidation

• Monika Kwoka and
• Maciej Krzywiecki

Beilstein J. Nanotechnol. 2017, 8, 514–521, doi:10.3762/bjnano.8.55

• air [28] as well as to partially ionized –OH groups [26] originating from, e.g., dissociated water. Such water dissociation was predicted by Xu et al. [29], where the splitting of water on metal oxide surfaces was modelled and investigated. The small relative decrease of overall signal intensity after

• led us to conclusion that carbonaceous and water-related species are partially strongly chemisorbed and partially physisorbed or weakly reversibly chemisorbed. Especially the water-related adsorbates are most probably a consequence of a partial dissociation of water vapor during the annealing process

Formation and shape-control of hierarchical cobalt nanostructures using quaternary ammonium salts in aqueous media

• Ruchi Deshmukh,
• Anurag Mehra and
• Rochish Thaokar

Beilstein J. Nanotechnol. 2017, 8, 494–505, doi:10.3762/bjnano.8.53

• chains, TEAH and TBAH. As the length of the alkyl chain increases, the dissociation of OH− ions decreases and affects the morphology thus achieved. The use of TEAH and TBAH generates particles with distinct surface topology and crystalline properties. Using TEAH, small nanoplates of approximately 50–70

• 1000 nm. The addition of TBAH yields nearly spherical nanoparticles with an average size of 250 nm (Figure 10c,d) suggesting isotropic growth of the crystals. The dissociation of hydroxide ions from TBAH is the least and TBA+ has the largest ionic radius of the additives used here. A general stability

Selective photodissociation of tailored molecular tags as a tool for quantum optics

• Ugur Sezer,
• Philipp Geyer,
• Moritz Kriegleder,
• Maxime Debiossac,
• Armin Shayeghi,
• Markus Arndt,
• Lukas Felix and
• Marcel Mayor

Beilstein J. Nanotechnol. 2017, 8, 325–333, doi:10.3762/bjnano.8.35

• signal was amplified and recorded by a fast digitizing oscilloscope. We verified that no ions were detected from the source in the absence of the VUV light. In order to test for photoinduced dissociation in high vacuum, a 266 nm UV laser beam was aligned parallel and counter-propagating to the molecular

• sections at 254 nm and 366 nm – but faster decay at higher photon energy. Preliminary dissociation experiments at 355 nm did not reveal any major cleavage of the trimer 1 at the laser energies that were sufficient to cleave the monomer 4 at 266 nm. Because of this, the following experiments were performed

• α = 0.64(8) and an in-vacuum beam depletion cross section σdep = 0.4(2) A2 = 4(2) × 10−17 cm2 where Φ is the laser fluence, i.e., the photon number in a single pulse per laser beam area. The depletion of the parent signal is attributed to photoactivated dissociation. To exclude the contribution of

Nitrogen-doped twisted graphene grown on copper by atmospheric pressure CVD from a decane precursor

• Ivan V. Komissarov,
• Nikolai G. Kovalchuk,
• Vladimir A. Labunov,
• Ksenia V. Girel,
• Olga V. Korolik,
• Mikhail S. Tivanov,
• Algirdas Lazauskas,
• Mindaugas Andrulevičius,
• Tomas Tamulevičius,
• Viktoras Grigaliūnas,
• Šarunas Meškinis,
• Sigitas Tamulevičius and
• Serghej L. Prischepa

Beilstein J. Nanotechnol. 2017, 8, 145–158, doi:10.3762/bjnano.8.15

• magnitude smaller than for a N2 dissociation process. For example, for the •CH + N2 = N + •CHN reaction this value was determined as 21.2 ± 0.7 kcal/mol [66]. Moreover, as it was proved by time-of-flight mass spectrometry experiments, various hydrocarbon radicals can be formed from n-decane just by thermal

Tandem polymer solar cells: simulation and optimization through a multiscale scheme

• Fanan Wei,
• Ligang Yao,
• Fei Lan,
• Guangyong Li and
• Lianqing Liu

Beilstein J. Nanotechnol. 2017, 8, 123–133, doi:10.3762/bjnano.8.13

• . The MC simulation was realized through the first reaction method (FRM) (the flow chart of FRM is presented in Supporting Information File 1, Figure S2). The details of FRM are illustrated in Supporting Information File 1. Based on the simulation of exciton transportation, dissociation and extinction

• processes, exciton dissociation efficiency (EDE, defined in Equation 1) was obtained, which is crucial for the calculation of charge carrier generation rate in the active layers. Electron and hole mobility was related to the average domain size and the electric field in the active layers. Since charge

Streptavidin-coated gold nanoparticles: critical role of oligonucleotides on stability and fractal aggregation

• Roberta D'Agata,
• Pasquale Palladino and
• Giuseppe Spoto

Beilstein J. Nanotechnol. 2017, 8, 1–11, doi:10.3762/bjnano.8.1

• properties of AuNP-SA-BiotinDNA, the competitive displacement of the biotinylated oligonucleotide from functionalized AuNPs was carried out. The dissociation of the very strong streptavidin–biotin complex (Kd ≈ 4 × 10−14 M) has been widely investigated both in homogeneous solution as well as at the solid

• –liquid interface [41][42][43][44][45][46][47]. When confined at the solid–liquid interface the whole interaction is influenced by factors that significantly affect the kinetics of the reaction. In particular, rate constants of the streptavidin–biotin dissociation in solution are smaller by a factor

• ranging from 10 to 102 than on the surface [42]. The kinetics of the interaction between biotinylated-oligonucleotide and avidin on the surface of SU-8 microparticles shows a dissociation constant of 7 ± 3 × 10−12 M [48] that is higher than that measured in solution for the same equilibrium. However, in

A novel electrochemical nanobiosensor for the ultrasensitive and specific detection of femtomolar-level gastric cancer biomarker miRNA-106a

• Maryam Daneshpour,
• Kobra Omidfar and
• Hossein Ghanbarian

Beilstein J. Nanotechnol. 2016, 7, 2023–2036, doi:10.3762/bjnano.7.193

• strategies such as using the thiol group, particle functionalization, and streptavidin–biotin interaction. Streptavidin has an extraordinary high affinity for biotin and the streptavidin–biotin bond is one of the strongest non-covalent interactions known in nature (with a dissociation constant in the order

Graphene-enhanced plasmonic nanohole arrays for environmental sensing in aqueous samples

• Christa Genslein,
• Peter Hausler,
• Eva-Maria Kirchner,
• Rudolf Bierl,
• Antje J. Baeumner and
• Thomas Hirsch

Beilstein J. Nanotechnol. 2016, 7, 1564–1573, doi:10.3762/bjnano.7.150

• is the signal change, c is the DEP concentration and K represents the equilibrium dissociation constant. All binding constants are almost identical, with the highest value for a D/P ratio of 0.43. This indicates a reproducible rGO layer deposition and no influence of the nanohole array structure on

Improved biocompatibility and efficient labeling of neural stem cells with poly(L-lysine)-coated maghemite nanoparticles

• Igor M. Pongrac,
• Marina Dobrivojević,
• Lada Brkić Ahmed,
• Michal Babič,
• Miroslav Šlouf,
• Daniel Horák and
• Srećko Gajović

Beilstein J. Nanotechnol. 2016, 7, 926–936, doi:10.3762/bjnano.7.84

• detector was used. The cytometer was set up to measure FSC linearly and SSC logarithmically. After labeling the NSCs were dissociated with StemPro Accutase (Life Technologies) cell dissociation reagent, washed with PBS, resuspended in PBS containing 2% FBS and 2 mM EDTA (pH 7.4) and passed through a 40 µm