Charge transfer from and to manganese phthalocyanine: bulk materials and interfaces

• Florian Rückerl,
• Daniel Waas,
• Bernd Büchner,
• Martin Knupfer,
• Dietrich R. T. Zahn,
• Francisc Haidu,
• Torsten Hahn and
• Jens Kortus

Beilstein J. Nanotechnol. 2017, 8, 1601–1615, doi:10.3762/bjnano.8.160

• . PES [37][38][39] is based on the photoelectric effect and provides insight into the valence-band electronic density of states as well as the binding energy and line shape of core levels, which give information about the composition of the sample and the chemical state (e.g., valency) of the atoms or

• ions. In IPES [19][40][41][42], the unoccupied density of states is probed. EELS [43][44][45] can also be called inelastic electron scattering and measures the electronic excitations either in the valence-band region, or from core levels into unoccupied states, whereas momentum-dependent studies are

• possible [43][45][46]. The EELS cross section is proportional to Im(−1/ε) (ε is the dielectric function). In this way, one can investigate valence-band excitations (cf. optical methods) and the element-projected unoccupied density of states. Also, access to orbital selective occupations and the magnetic

Adsorption and electronic properties of pentacene on thin dielectric decoupling layers

• Sebastian Koslowski,
• Daniel Rosenblatt,
• Alexander Kabakchiev,
• Klaus Kuhnke,
• Klaus Kern and
• Uta Schlickum

Beilstein J. Nanotechnol. 2017, 8, 1388–1395, doi:10.3762/bjnano.8.140

• well-defined increases in the local density of states are observed close to the Fermi level [3][4]. Tunneling through these states of pentacene results in a temporary charging of the molecule prior to the dissipation of the charge into the substrate [5]. The peaks observed in STS on pentacene are

Ultrasmall magnetic field-effect and sign reversal in transistors based on donor/acceptor systems

• Thomas Reichert and
• Tobat P. I. Saragi

Beilstein J. Nanotechnol. 2017, 8, 1104–1114, doi:10.3762/bjnano.8.112

• ][36][37][38]. Doping of amorphous organic films results in a broadening of the density of states and, thus, is increasing the energetic disorder [39][40]. Therefore, the high density of intrinsic charges in Spiro-TTB/HAT-CN compositions as well as the broadened density of states leads to an increased

Stable Au–C bonds to the substrate for fullerene-based nanostructures

• Taras Chutora,
• Jesús Redondo,
• Bruno de la Torre,
• Martin Švec,
• Pavel Jelínek and
• Héctor Vázquez

Beilstein J. Nanotechnol. 2017, 8, 1073–1079, doi:10.3762/bjnano.8.109

• the electronic properties of the adsorbed fullerenes with vacancy defect, and compare them to those of the C60/Au(111) system. Figure 5 shows the calculated density of states (DOS) of the isolated molecule (dashed lines) and junction (solid lines) projected onto the molecular atoms. Upon adsorption

Near-field surface plasmon field enhancement induced by rippled surfaces

• Mario D’Acunto,
• Francesco Fuso,
• Ruggero Micheletto,
• Makoto Naruse,
• Francesco Tantussi and
• Maria Allegrini

Beilstein J. Nanotechnol. 2017, 8, 956–967, doi:10.3762/bjnano.8.97

• is characterized by N ≈ 1 hot spots with localized length ξl whereas delocalized modes involve N >> 1 hot spots, with average length ξ >> ξl so that for localized modes χ ≈ ξl−2. Carminati et al. have shown that high values of the χ parameter correspond to large fluctuations of the local density of

• states (LDOSs) [52]. Each QNM is described by the Green’s functions, Equation 9 and Equation 12, that are closely related to the LDOSs. The LDOSs represents the weight of all normalized QNMs at a certain point of space for a certain light frequency and can be calculated by Equation 16. In Equation 16 G

Energy-level alignment at interfaces between manganese phthalocyanine and C₆₀

• Daniel Waas,
• Florian Rückerl,
• Martin Knupfer and
• Bernd Büchner

Beilstein J. Nanotechnol. 2017, 8, 927–932, doi:10.3762/bjnano.8.94

• deposited first and the metal substrate (gold) varies going from MnPc to C60 with the consequence of a different Fermi-level position in the layer stack. Moreover, in previous studies [25][53] the importance of interface morphologies, molecular orientations and the resulting density of states on the energy

Advances in the fabrication of graphene transistors on flexible substrates

• Gabriele Fisichella,
• Stella Lo Verso,
• Silvestra Di Marco,
• Vincenzo Vinciguerra,
• Emanuela Schilirò,
• Salvatore Di Franco,
• Raffaella Lo Nigro,
• Fabrizio Roccaforte,
• Amaia Zurutuza,
• Alba Centeno,
• Sebastiano Ravesi and
• Filippo Giannazzo

Beilstein J. Nanotechnol. 2017, 8, 467–474, doi:10.3762/bjnano.8.50

• in graphene FETs (Gr-FETs) even with gradually scaled (≈0.5 µm) channel lengths fabricated on a flexible polyimide substrate and adopting a back-gate configuration and Al2O3 as a gate dielectric. In addition, due to the low density of states (DOS) around the Dirac point, the carrier density of

Tunable plasmons in regular planar arrays of graphene nanoribbons with armchair and zigzag-shaped edges

• Cristian Vacacela Gomez,
• Michele Pisarra,
• Mario Gravina and
• Antonello Sindona

Beilstein J. Nanotechnol. 2017, 8, 172–182, doi:10.3762/bjnano.8.18

• region is further scrutinized with a finer MP mesh of 2000 × 1 × 1 k-points, including up to 30 bands. The main results of our DFT computations are summarized in the plots of Figure 1, which show the different geometry, band structure and density of states (DOS) of the GNR arrays. 4ZGNR and 10ZGNR behave

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

• graphene planes [5][6]. For SLG, the Fermi velocity reaches the value 106 m/s for θ > 10° and drastically decreases for θ < 5° [5]. In addition, one of the most attractive characteristics of TG is the pair of logarithmic divergences in the density of states, known as the van Hove singularities (vHs), which

Effect of Anderson localization on light emission from gold nanoparticle aggregates

• Mohamed H. Abdellatif,
• Marco Salerno,
• Gaser N. Abdelrasoul,
• Ioannis Liakos,
• Alice Scarpellini,
• Sergio Marras and
• Alberto Diaspro

Beilstein J. Nanotechnol. 2016, 7, 2013–2022, doi:10.3762/bjnano.7.192

• lead to coherent scattering [5] and pronounced spatial fluctuations in the local density of states, where the wavefunction of the optical mode is localized and exhibits a fractal shape [6][7][8]. The localized modes have energy , which present a highly sensitive dependence on the dimensionality and

• for the slowing down of the nonradiative relaxation of excited carriers is the size-induced opening of a gap in the density of states, which is very common in gold particles smaller than 3 nm diameter, where the density of states is far from bulk [52]. However, our AuNPs are of 14 nm average diameter

Zigzag phosphorene nanoribbons: one-dimensional resonant channels in two-dimensional atomic crystals

• Carlos. J. Páez,
• Dario. A. Bahamon,
• Ana L. C. Pereira and
• Peter. A. Schulz

Beilstein J. Nanotechnol. 2016, 7, 1983–1990, doi:10.3762/bjnano.7.189

• contact ΣL(R) are calculated recursively for the semi-infinite zigzag phosphorene nanoribbons [23]. Other electronic properties such as the local density of states (LDOS) are also calculated. The electronic and transport properties of a host zizgzag nanoribbon, in which a finite segment will be latter

• (keeping the central band of the contacts unaltered). In our constriction the role of both channels (discrete states and continuum at the upper and lower edges) can be made explicit by picturing the local density of states (LDOS) in Figure 4, at the energy values indicated by arrows 1, 2, 3 and 4 in Figure

Monolayer graphene/SiC Schottky barrier diodes with improved barrier height uniformity as a sensing platform for the detection of heavy metals

• Ivan Shtepliuk,
• Jens Eriksson,
• Volodymyr Khranovskyy,
• Tihomir Iakimov,
• Anita Lloyd Spetz and
• Rositsa Yakimova

Beilstein J. Nanotechnol. 2016, 7, 1800–1814, doi:10.3762/bjnano.7.173

• properties, such as Fermi level, work function, density of states, C–С bond lengths. Once we know the influence of heavy metals on the work function of graphene, we can predict the values of the Schottky barrier height and output characteristics of the devices (for example current–voltage characteristics

• graphene system to the amount of Hg atoms and a stronger sensitivity on the number of Pb and Cd atoms. In the case of Pb adsorption, the energy gap dependence follows the binding energy dependence on the amount of Pb atoms. This finding is substantiated by the projected density of states in Figure 8. The

Nonlinear thermoelectric effects in high-field superconductor-ferromagnet tunnel junctions

• Stefan Kolenda,
• Peter Machon,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2016, 7, 1579–1585, doi:10.3762/bjnano.7.152

• as Here G(E) is the spectral conductance and fT(E) = (exp(E/kBT) + 1)−1 is the Fermi function at energy E. The spectral conductance is given by where N0 = (N+ + N−)/2, Nz = (N+ − N−)/2, and the spin-resolved density of states in the superconductor is N±(E). We would like to point out that N0 is even

• spin-dependent density of states (left). Heating of the ferromagnet leads to a flow of spin-up electrons at positive energy from occupied states in the ferromagnet into the superconductor, and a flow of spin-down electrons out of the superconductor into unoccupied states in the ferromagnet at negative

• vanishes. These conditions are therefore potentially useful for applications in thermometry or cooling. One possible way to improve performance is therefore to increase the spin splitting of the density of states by spin-active scattering with a ferromagnetic insulator [28][29], which is known to enhance

Diameter-driven crossover in resistive behaviour of heavily doped self-seeded germanium nanowires

• Stephen Connaughton,
• Maria Koleśnik-Gray,
• Richard Hobbs,
• Olan Lotty,
• Justin D. Holmes and
• Vojislav Krstić

Beilstein J. Nanotechnol. 2016, 7, 1284–1288, doi:10.3762/bjnano.7.119

• parameters of bulk germanium we determined the positions of the heavy and light hole sub-band minima along with the corresponding density of states (Supporting Information File 1). The density of states for heavy holes was found to dominate and therefore these can be considered as the main carrier type. The

• density of states at the bottom of sub-bands involved (Supporting Information File 1) and thus is responsible for the peak feature: The carrier concentration increases with diameter reduction (acting to lower the resistivity), in opposition to the decreasing mobility. That is, when the mobility is

Photocurrent generation in carbon nanotube/cubic-phase HfO₂ nanoparticle hybrid nanocomposites

• Protima Rauwel,
• Augustinas Galeckas,
• Martin Salumaa,
• Frédérique Ducroquet and
• Erwan Rauwel

Beilstein J. Nanotechnol. 2016, 7, 1075–1085, doi:10.3762/bjnano.7.101

• optical properties of CNTs derive from electronic transitions within the one-dimensional density of states (DOS), which is discontinuous in nature and exhibits sharp peaks called van Hove singularities (vHS) [38]. The energy separations between the vHS in the valence and conduction bands depend on the

A terahertz-vibration to terahertz-radiation converter based on gold nanoobjects: a feasibility study

• Kamil Moldosanov and
• Andrei Postnikov

Beilstein J. Nanotechnol. 2016, 7, 983–989, doi:10.3762/bjnano.7.90

• text for details. Vibrational density of states of gold as extracted from (a) inelastic neutron scattering on thick foils [2], (b) plasmon resonance Raman scattering on nanocrystals [3] (green dots) and reconstructed from force constants fitted to inelastic neutron scattering data from massive single

• the energy of approx. 17.4 meV (or close to it, according to that of the “primary” photon). In order to reduce the probability of elastic scattering of the electron at the GNB boundary, and hence to enforce the decay probability into THz photon emission, one can try to enhance the electron density of

• states at the Fermi level. This can be achieved, e.g., by ion implantation of Ta or Fe impurities into the subsurface layer of nanoobjects. The idea is that the doping of bulk gold with Ta or Fe atoms creates impurity d-levels (in one of the spin channels, since the impurities are magnetic) at the Fermi

Charge and heat transport in soft nanosystems in the presence of time-dependent perturbations

• Alberto Nocera,
• Carmine Antonio Perroni,
• Vincenzo Marigliano Ramaglia and
• Vittorio Cataudella

Beilstein J. Nanotechnol. 2016, 7, 439–464, doi:10.3762/bjnano.7.39

• dot and a state k in the lead α has in general a time-dependent amplitude . For the sake of simplicity, we will suppose that the density of states ρk,α for the leads is flat within the wide-band approximation: , , with being periodic functions describing the strength of the pumping external

Invariance of molecular charge transport upon changes of extended molecule size and several related issues

• Ioan Bâldea

Beilstein J. Nanotechnol. 2016, 7, 418–431, doi:10.3762/bjnano.7.37

• description based on the small molecule or on an extended molecule, all the physical properties (e.g., transmission, current, local density of states, charge densities) should be identical. The proof that these properties indeed coincide, which represents an important sanity test for theory, will be given

• Equation 27 coincide with the exact one (Equation 15). Via Equation 8 and Equation 2 (see also Table 1), this implies that conductance and local density of states at equilibrium (V = 0) and zero temperature computed within the wide- or flat-band approximations are exact. Therefore, these quantities (as

• density of states at the contacts [21]). Electron correlations, which escape the conventional Landauer framework utilized here, can further enhance the NDR [25][26][27]. Besides finite bandwidth and energy-dependent densities of states, for systems with more than one site, the potential drop across the

Rigid multipodal platforms for metal surfaces

• Michal Valášek,
• Marcin Lindner and
• Marcel Mayor

Beilstein J. Nanotechnol. 2016, 7, 374–405, doi:10.3762/bjnano.7.34

• reproducible binding, sufficiently strong anchoring between a molecule and metal surfaces, and should maintain a sufficient electron density of states close to the Fermi level to pass an electron or hole through the molecule (electronically transparent nature with relatively high conductance). Finally, a well

Current-induced runaway vibrations in dehydrogenated graphene nanoribbons

• Rasmus Bjerregaard Christensen,
• Jing-Tao Lü,
• Per Hedegård and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2016, 7, 68–74, doi:10.3762/bjnano.7.8

• fluctuating force, f, while the current-induced forces show up in . Here we focus on the latter. The contribution from the electron degrees of freedom including the non-equilibrium effects can be expressed in terms of the coupling-weighted electron–hole pair density of states, Λ, with Λ (including spin

• phonon density of states (DOS) as, where Dr(ω) is the nonequilibrium phonon Greens function obtained from the SCLE, Note that we introduced boldface to underline that these are matrices with mode-index (k,l). Contrary to the equilibrium situation, the DOS given in Equation 8 can take negative values at

• used below in Figure 2). (c) Solid line is phonon transmission for the structure in (a), dotted line is phonon transmission for a pristine hydrogenated ribbon. (a) The black solid line shows the phonon density of states excluding the self-energy due to the electronic degrees of freedom. The green

Large area scanning probe microscope in ultra-high vacuum demonstrated for electrostatic force measurements on high-voltage devices

• Urs Gysin,
• Thilo Glatzel,
• Thomas Schmölzer,
• Adolf Schöner,
• Sergey Reshanov,
• Holger Bartolf and
• Ernst Meyer

Beilstein J. Nanotechnol. 2015, 6, 2485–2497, doi:10.3762/bjnano.6.258

• effective density of states in the conduction (NC = 3.25 × 1015·T3/2 = 1.69 × 1019 cm−3) and valence band (NV = 4.8 × 1015·T3/2 = 2.49 × 1019 cm−3) [46]. This leads to Vb = 3.0 eV, which is a reasonable value taking into account the band gap of 4H-SiC. With a theoretically determined electron affinity of χ

Vibration-mediated Kondo transport in molecular junctions: conductance evolution during mechanical stretching

• David Rakhmilevitch and
• Oren Tal

Beilstein J. Nanotechnol. 2015, 6, 2417–2422, doi:10.3762/bjnano.6.249

• density of states at the Fermi energy, which is expressed as a peak in the conductance at zero voltage (Figure 1a). At a finite voltage and in the absence of inelastic effects, the injected electrons are transmitted off-resonance and the Kondo contribution to the conductance is reduced. However, in the

Negative differential electrical resistance of a rotational organic nanomotor

• Hatef Sadeghi,
• Sara Sangtarash,
• Qusiy Al-Galiby,
• Rachel Sparks,
• Steven Bailey and
• Colin J. Lambert

Beilstein J. Nanotechnol. 2015, 6, 2332–2337, doi:10.3762/bjnano.6.240

• . Figure 3b shows contour plots of the local density of states (LDOS) around the HOMO of the isolated molecule for two different rotation angles. These plots show that the HOMO is extended, but not symmetric. This demonstrates why the transmission coefficient does not approach unity on resonance, because

• –angle curves, the pendant group was artificially rotated to a chosen angle and then the molecule was allowed to relax to a local energy minimum. (a) The molecular structure within the junction. (b) A contour plot of the local density of states of the gas-phase molecule at θ = 60° (right) and θ = 0

Plasma fluorination of vertically aligned carbon nanotubes: functionalization and thermal stability

• Claudia Struzzi,
• Mattia Scardamaglia,
• Axel Hemberg,
• Luca Petaccia,
• Jean-François Colomer,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2015, 6, 2263–2271, doi:10.3762/bjnano.6.232

• eV, respectively. The strong modification in the intensity ratio of the structures in the UPS spectrum is due to the fluorine grafting that also drastically reduces the relative intensity associated with the density of states just below the Fermi level. This is a signature of a drastic change in the

• more intense. Moreover, the relative intensity related to the density of states near the Fermi level increases again. This shows that the oxygen effect in the electronic properties is less pronounced at this concentration. This is in contrast to the presence of fluorine, which induces a semiconducting

• completely at around 540 °C, the oxygen atoms were strongly bound to the carbon lattice through single and double C–O covalent bonds. This illustrated its electronic states also in the valence band, where we observed a fine tuning of the density of states near the Fermi level by the desorption of fluorine

Nonconservative current-driven dynamics: beyond the nanoscale

• Brian Cunningham,
• Tchavdar N. Todorov and
• Daniel Dundas

Beilstein J. Nanotechnol. 2015, 6, 2140–2147, doi:10.3762/bjnano.6.219

• density of states operators are generated by Green’s function techniques. We can now calculate the forces on ions about a chosen reference geometry, . Under small displacements, d, where Knm = −∂ Fn()/∂ Rm are the elements of the dynamical response matrix. The dynamical response matrix determines the