Surface energy of nanoparticles – influence of particle size and structure

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

Beilstein J. Nanotechnol. 2018, 9, 2265–2276, doi:10.3762/bjnano.9.211

• definition of the particle size. A more realistic definition of the particle size is possible only by a detailed analysis of the electronic structure obtained from initio calculations. Except for minor variations caused by changes in the structure, only a minor dependence of the surface energy on the

• to take care of the “electron spill-out”. De Heer proposed a correction of the particle radius of approximately 0.045–0.079 nm. According to the results of a very detailed study of the electronic structure by Holec et al. [53], the value for the correction of the diameter should be in the range of an

• 0.045 nm to 0.079 nm. According to the results of a very detailed study of the electronic structure by Holec et al. [53] the value for the correction of the diameter should be in the range of an atomic diameter (≈0.288 nm). Figure 16 displays the original values of the surface energy and that after

Intrinsic ultrasmall nanoscale silicon turns n-/p-type with SiO₂/Si₃N₄-coating

• Dirk König,
• Daniel Hiller,
• Noël Wilck,
• Birger Berghoff,
• Merlin Müller,
• Sangeeta Thakur,
• Giovanni Di Santo,
• Luca Petaccia,
• Joachim Mayer,
• Sean Smith and
• Joachim Knoch

Beilstein J. Nanotechnol. 2018, 9, 2255–2264, doi:10.3762/bjnano.9.210

• ) approach. Following an explanation of the theoretical and experimental methods used, we turn to results for Si-NCs obtained from h-DFT. Here, we focus on the electronic structure of Si-NCs as a function of the embedding dielectric and its thickness of up to 3 monolayers (MLs). The latter dependence

• optimized geometries, their electronic structure was calculated again by testing and optimizing the MO-BS wavefunction ensemble with the B3LYP hybrid DF [19][20] and the Gaussian-type 6-31G(d) MO-BS which contains d-polarization functions (B3LYP/6-31G(d)) [21] to describe the strong polar nature of atomic

• electronic structure of the Si233(NH2)87(OH)81 NWire allows ΔE values to be established for NWire electronic devices with a combined SiO2-/Si3N4-coating such as an undoped self-blocking p-channel FET (Figure 7). Using the ΔE value obtained from the Si233(NH2)87(OH)81 NWire approximant and above-described UPS

Metal-free catalysis based on nitrogen-doped carbon nanomaterials: a photoelectron spectroscopy point of view

• Mattia Scardamaglia and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2018, 9, 2015–2031, doi:10.3762/bjnano.9.191

• ) energies. A quarter of the target was cut out for a better visualization. (b) Impact of an ion onto a carbon nanotube, a quasi-1D system. The excess energy is dissipated in only two directions, which may affect the temperature profile and give rise to additional defects. (c) The sketch of the electronic

• structure of bulk and nanoscale objects, illustrating the so-called “phonon bottleneck” phenomenon. The excitation relaxation time is enhanced when the spacing between the size-quantized energy levels ΔE is larger than the vibrational energy ħω. This mechanism is discussed for illustration purposes only

Improving the catalytic activity for hydrogen evolution of monolayered SnSe_2(1−x)S_2x by mechanical strain

• Sha Dong and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2018, 9, 1820–1827, doi:10.3762/bjnano.9.173

• %) and tensile (14%) strain can trigger the semiconductor–metal transition in the SnSe2 monolayer. Furthermore, Scalise et al. [15] showed that the electronic structure of the MoS2 monolayer can be reversibly tuned from direct to indirect by applying strain (ca. 2%). Much research effort has been devoted

• trace amounts of Pt nanoparticles interacting with defect-rich SnS2; the results demonstrated that SnS2 may offer new perspectives regarding a utilization in HER. The catalytic activity for HER shows great dependence on the electronic structure of the catalyst. As alloying and strain can be used to tune

Electronic conduction during the formation stages of a single-molecule junction

• Atindra Nath Pal,
• Tal Klein,
• Ayelet Vilan and
• Oren Tal

Beilstein J. Nanotechnol. 2018, 9, 1471–1477, doi:10.3762/bjnano.9.138

• between the two conductance pathways via the molecular bridge and across the metallic one is characterized in terms of additive independent conductance pathways, quantum interference between the two pathways, and deformed electronic structure by the presence of molecules. Finally, we reveal the different

• by two main channels, each with lower conductance contribution than 1 G0. The deviation from the trivial channel distribution can stem from distorted local electronic structure at the single-atom junction due to the presence of the molecular bridge or other nearby adsorbed molecules, such that the

• distance). Alternatively, quantum interference between the molecular and the atomic pathways can generate such nontrivial channel distribution. The first option (i.e., distortion of the local electronic structure) should also lead to asymmetric widening of the 1 G0 peak in the conductance histogram towards

Robust midgap states in band-inverted junctions under electric and magnetic fields

• Álvaro Díaz-Fernández,
• Natalia del Valle and
• Francisco Domínguez-Adame

Beilstein J. Nanotechnol. 2018, 9, 1405–1413, doi:10.3762/bjnano.9.133

• states arising in the single-junction configuration is robust against crossed electric and magnetic fields. In addition, Landau levels of electron states lying in the semiconductor bands can be tailored by the electric field. Finally, the electronic structure of band-inverted junctions when the magnetic

Predicting the strain-mediated topological phase transition in 3D cubic ThTaN₃

• Chunmei Zhang and
• Aijun Du

Beilstein J. Nanotechnol. 2018, 9, 1399–1404, doi:10.3762/bjnano.9.132

• external strain. All these materials possess heavy elements and the strong SOC can induce a band inversion, which is a typical mechanism for TIs [26][27]. The experimentally observed pressure-induced phase transition in ThTaN3 indicates that the electronic structure of 3D ThTaN3 is likely very sensitive to

• (Figure 1c), the band gap reduction is significantly high (0.26 eV) after the incorporation of SOC. Then we turned to study the effect of strain [37] on the electronic structure of c-PV ThTaN3 by applying a hydrostatic strain ranging from −10% (compressive strain) to +15% (tensile strain) on 3D ThTaN3. As

• great potential for application of ThTaN3 in electronics. As eluded to above, the effect of SOC on the band gap of ThTaN3 is significant. It is therefore important to further study the effect of strain on the electronic structure of ThTaN3 in the presence of SOC (Figure 3). For strain-free ThTaN3, the

Theoretical study of strain-dependent optical absorption in a doped self-assembled InAs/InGaAs/GaAs/AlGaAs quantum dot

• Tarek A. Ameen,
• Hesameddin Ilatikhameneh,
• Archana Tankasala,
• Yuling Hsueh,
• James Charles,
• Jim Fonseca,
• Michael Povolotskyi,
• Jun Oh Kim,
• Sanjay Krishna,
• Monica S. Allen,
• Jeffery W. Allen,
• Rajib Rahman and
• Gerhard Klimeck

Beilstein J. Nanotechnol. 2018, 9, 1075–1084, doi:10.3762/bjnano.9.99

• -based projection methods [14][15]. Each atom has 20 orbitals in the sp3d5s*_SO tight-binding basis. Strain and electronic structure simulations of such large systems are computationally demanding and require highly scalable computational codes. The code used for our simulations is the Nano Electronic

• expressions for the strain components in quantum wells are = (aGaAs − aInAs)/aInAs and [24], where a is the lattice constant. Electronic structure and absorption The eigenstates of the system were calculated with a Hamiltonian constructed from semi-empirical tight-binding sp3d5s*_SO basis. The Slater–Koster

An implementation of spin–orbit coupling for band structure calculations with Gaussian basis sets: Two-dimensional topological crystals of Sb and Bi

• Sahar Pakdel,
• Mahdi Pourfath and
• J. J. Palacios

Beilstein J. Nanotechnol. 2018, 9, 1015–1023, doi:10.3762/bjnano.9.94

• insulator, and to mono- and multilayer Sb(111) (also known as antimonene), the former being a trivial semiconductor and the latter a topological semimetal featuring topologically protected surface states. Keywords: antimonene; electronic structure; Sb few-layers; spin–orbit coupling (SOC); topological

• parameters to the specific structural variations which also needs to be parametrized [10]. On the opposite side of sophistication, the electronic structure of topological materials can be evaluated through density functional theory (DFT). According to the type of basis sets, DFT codes fall into two broad

• once a standard non-relativistic or scalar relativistic DFT calculation based on localized orbitals has been performed. Methodology Gaussian basis sets The accuracy of electronic structure calculations is limited, not only by functional, but also by the basis set used to expand the wave functions. When

Cyclodextrin inhibits zinc corrosion by destabilizing point defect formation in the oxide layer

• Abdulrahman Altin,
• Maciej Krzywiecki,
• Adnan Sarfraz,
• Cigdem Toparli,
• Claudius Laska,
• Philipp Kerger,
• Aleksandar Zeradjanin,
• Karl J. J. Mayrhofer,
• Michael Rohwerder and
• Andreas Erbe

Beilstein J. Nanotechnol. 2018, 9, 936–944, doi:10.3762/bjnano.9.86

• conductive, not inhibiting further corrosion. The oxide formed on metallic Zn has noticeably different properties than crystalline bulk ZnO, due to the presence of different point defects, which have a strong effect on the electronic structure of the oxide [21][22]. ADXPS was utilized to understand defect

• levels, electronic structure, and chemical composition of the zinc surface, based on a previously established method [23][24]. Results from the β-CD/ZnO system are shown in Figure 3. Take-off-angles (TOA) close to 90° probe deeper into the volume of the sample, while low TOAs weigh surface contributions

• from impurities collected through the sample transfer. Due to the high symmetry of the Zn 2p3/2 peak, analysis of the Auger parameter α was needed to understand the electronic structure of the layer (Figure 3c). Figure 3d shows the Zn 3d region, including an inset with the depth dependence of the ZnO

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

• ]. Values of the hardness >3 eV and softness <0.1 eV indicate high chemical stability and hence 2 can be considered as such, indicating reliability of the approach applied. This nicely corresponds with the experimentally observed properties of 2 (see above). The electronic structure of monomeric 2 is

Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions

• Youngsang Kim,
• Safa G. Bahoosh,
• Dmytro Sysoiev,
• Thomas Huhn,
• Fabian Pauly and
• Elke Scheer

Beilstein J. Nanotechnol. 2017, 8, 2606–2614, doi:10.3762/bjnano.8.261

• Konstanz, Germany Department of Chemistry, University of Konstanz, 78457 Konstanz, Germany Okinawa Institute of Science and Technology Graduate University, Onna-son, Okinawa 904-0395, Japan 10.3762/bjnano.8.261 Abstract Diarylethene-derived molecules alter their electronic structure upon transformation

• particularly promising because of the negligible change of molecular length between the two isomers (i.e., open and closed forms) and the possibility for further chemical functionalization [13][14]. The isomerization upon illumination with appropriate wavelengths tunes the electronic structure of the molecules

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

• deposition (FEBID); photoabsorption; tungsten hexacarbonyl; Introduction The electronic structure of tungsten hexacarbonyl, W(CO)6, has previously been studied by using a variety of different experimental and theoretical methods, with experiments including vacuum ultraviolet experiments in the wavelength

• ]. The main features have been identified as bands I to V and their main characteristics are discussed below, with a complete overview and assignment of the electronic structure. The TDDFT calculations with SOC predict an important contribution of the triplet states for bands III and IV as discussed

Substrate and Mg doping effects in GaAs nanowires

• Perumal Kannappan,
• Nabiha Ben Sedrine,
• Jennifer P. Teixeira,
• Maria R. Soares,
• Bruno P. Falcão,
• Maria R. Correia,
• Nestor Cifuentes,
• Emilson R. Viana,
• Marcus V. B. Moreira,
• Geraldo M. Ribeiro,
• Alfredo G. de Oliveira,
• Juan C. González and
• Joaquim P. Leitão

Beilstein J. Nanotechnol. 2017, 8, 2126–2138, doi:10.3762/bjnano.8.212

• the GaAs nanowires on their electronic structure; ii) a considerable reduction of the density of vertical nanowires, which is almost null for growth on Si(111); iii) the occurrence of a higher WZ phase fraction, in particular for growth on Si(111); iv) an increase of the activation energy to release

• measurements showed a lower influence of the polytypic structure of the nanowires on their electronic structure. The involvement of Mg in one of the radiative transitions observed for growth on the Si(111) substrate is suggested. Keywords: electronic structure; field effect transistors; GaAs nanowires

• in the nanowires. The highest mobility was obtained for the highest free hole concentration, suggesting that, in our case, the increase of free holes in the valence band progressively blurs the contribution of the polytypic nature of the nanowires on the electronic structure [61]. The obtained PL

Electronic structure, transport, and collective effects in molecular layered systems

• Torsten Hahn,
• Tim Ludwig,
• Carsten Timm and
• Jens Kortus

Beilstein J. Nanotechnol. 2017, 8, 2094–2105, doi:10.3762/bjnano.8.209

• describe the essential theoretical tools to obtain the parameters needed for the master equation from DFT results. Finally, an interacting molecular monolayer is considered within a master-equation approach. Keywords: electron correlation; electronic structure; quantum transport; spin transport

• molecules, the hybrid dimer states close to the Fermi level in the the picene/F4TCNQ compound excite a very asymmetric I–V curve with a pronounced diode-like forward/reverse current behavior. Additinally the effect of an applied gate voltage is greatly enhanced [13]. The electronic structure of free

• the microscopic details of the interface. The question arises of how the substrate interactions change the electronic structure of the molecular material and whether favorable properties for envisaged applications can be realized. Another important aspect for transport and potential applications are

Adsorbate-driven cooling of carbene-based molecular junctions

• Giuseppe Foti and
• Héctor Vázquez

Beilstein J. Nanotechnol. 2017, 8, 2060–2068, doi:10.3762/bjnano.8.206

• that the charge rearrangement resulting from the adsorbate gates the carbene electronic structure and reduces the density of carbene states near the Fermi level as a function of bias. These effects result in the cooling of carbene modes at all voltages compared to the “clean” carbene-based junction. We

• a first-principles, self-consistent description of the junction out of equilibrium based on density functional theory (DFT) and non-equilibrium Green’s functions (NEGF). We show how the change in the electronic structure of the junction induced by the presence of the adsorbate promotes the cooling

• gating from that of the reduction of carbene DOS near the Fermi level due to the adsorbate. The current-induced heating of adsorbate modes reveals the important role of molecule–adsorbate through-space tunneling. By setting the adsorbate electronic structure elements to zero in the calculations we could

Identifying the nature of surface chemical modification for directed self-assembly of block copolymers

• Laura Evangelio,
• Federico Gramazio,
• Matteo Lorenzoni,
• Michaela Gorgoi,
• Francisco Miguel Espinosa,
• Ricardo García,
• Francesc Pérez-Murano and
• Jordi Fraxedas

Beilstein J. Nanotechnol. 2017, 8, 1972–1981, doi:10.3762/bjnano.8.198

• the block copolymers. We have chosen hard X-ray high kinetic energy photoelectron spectroscopy as an exploration technique because it provides information on the electronic structure of buried interfaces. The outcome of the characterization sheds light onto key aspects of directed self-assembly

• photoelectron spectroscopy (HAXPES) [14]. Photoemission is a well-known technique which provides information on the electronic structure of surfaces. Its high surface sensitivity arises from the small mean free path of the outcoming photoelectrons in solid matter. Using conventional excitation sources, kinetic

Structural model of silicene-like nanoribbons on a Pb-reconstructed Si(111) surface

• Agnieszka Stępniak-Dybala and
• Mariusz Krawiec

Beilstein J. Nanotechnol. 2017, 8, 1836–1843, doi:10.3762/bjnano.8.185

• obtained electronic structure data of the Si NRs/Si(111) system described above, scanning tunneling microscopy simulations were performed by using the Tersoff–Hamann approach [52]. Results and Discussion Typical Si nanoribbons are several nanometers long and run in one of three high-symmetry directions of

(Metallo)porphyrins for potential materials science applications

• Lars Smykalla,
• Carola Mende,
• Michael Fronk,
• Pablo F. Siles,
• Michael Hietschold,
• Georgeta Salvan,
• Dietrich R. T. Zahn,
• Oliver G. Schmidt,
• Tobias Rüffer and
• Heinrich Lang

Beilstein J. Nanotechnol. 2017, 8, 1786–1800, doi:10.3762/bjnano.8.180

• (111). Manipulation of the electronic structure of H2TPP(OH)4 on Au(111) [45]: Molecules with two possible states, e.g., of conductivity, can be used as single-molecule switches. This functionality could be applied in nano-scaled molecular-based memory devices or logic gates [64], However, one must be

• from [44], copyright 2014 Elsevier. (a–e) Manipulation of the electronic structure by applying a voltage pulse with the STM tip at the position marked with a white circle. Converted molecules are marked with green (1→2) or blue (2→1) rectangles. (a–c) 1→2→1 conversion with 2 V pulses for 3 s (feedback

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

• higher binding energy values. The valence band spectra of highly fluorinated sample are conversely dominated by the high cross section of the F 2p valence states, whose contribution strongly attenuates the pristine electronic structure from the Fermi level up to 20 eV. In particular, we can assign the

Transport characteristics of a silicene nanoribbon on Ag(110)

• Ryoichi Hiraoka,
• Chun-Liang Lin,
• Kotaro Nakamura,
• Ryo Nagao,
• Maki Kawai,
• Ryuichi Arafune and
• Noriaki Takagi

Beilstein J. Nanotechnol. 2017, 8, 1699–1704, doi:10.3762/bjnano.8.170

• preserves the electronic states localized at the edges near the Fermi level similar to the graphene nanoribbon with zigzag edges [29][30][31][32][33]. Although the electronic structure of SiNR has been studied experimentally [34][35][36], the existence of edge states remains an open question. The

• pentagonal chain models proposed very recently for SiNRs on Ag(110) [27][28]. Cerdá et al. [27] calculated the energy band structures of various pentagonal chains; some of the pentagonal chains host electronic structure around the Fermi level, which may explain the peak structure observed in our conductance

• investigated the geometric and electronic structure of SiNRs grown on Ag(110) using STM and STM junction measurements. We found that the dI/dV spectra of SiNRs on Ag(110) and the bare Ag(110) regions are essentially identical, indicating strong interfacial coupling between the SiNR and the Ag(110) substrate

Effect of the fluorination technique on the surface-fluorination patterning of double-walled carbon nanotubes

• Lyubov G. Bulusheva,
• Yuliya V. Fedoseeva,
• Emmanuel Flahaut,
• Jérémy Rio,
• Christopher P. Ewels,
• Victor O. Koroteev,
• Gregory Van Lier,
• Denis V. Vyalikh and
• Alexander V. Okotrub

Beilstein J. Nanotechnol. 2017, 8, 1688–1698, doi:10.3762/bjnano.8.169

• fluorine addition on the DWCNT surface during a particular fluorination procedure, we carried out simulations of the NEXAFS spectra of the fluorinated samples. NEXAFS spectroscopy is widely used for probing the surface chemical functionalities and the electronic structure of CNTs and related nanomaterials

Oxidative stabilization of polyacrylonitrile nanofibers and carbon nanofibers containing graphene oxide (GO): a spectroscopic and electrochemical study

• İlknur Gergin,
• Ezgi Ismar and
• A. Sezai Sarac

Beilstein J. Nanotechnol. 2017, 8, 1616–1628, doi:10.3762/bjnano.8.161

• ratio between D band and G band (R = ID/IG) indicates structurally ordered graphite crystallites [30][54]. The R value of CNF is around 0.9. A lower R value means a more crystalline material with higher conductivity [56]. Position and intensity of D and G band demonstrate the electronic structure and

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

• Photocatalytic H2 production through solar water splitting has been widely explored as it has several advantages like easy and abundant availability of raw materials, tunable electronic structure and the fact that combustion of hydrogen in air produces water; hence, this method is ecologically-friendly [96

Parylene C as a versatile dielectric material for organic field-effect transistors

• Tomasz Marszalek,
• Maciej Gazicki-Lipman and
• Jacek Ulanski

Beilstein J. Nanotechnol. 2017, 8, 1532–1545, doi:10.3762/bjnano.8.155

• of organic electronics. One of the early applications of Parylene C encapsulation layer in an electronic structure was that of a microelectrode insulator [65]. The Parylene C-covered iridium and tungsten microelectrodes were investigated by means of in vivo and in vitro impedance tests. In vitro