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

• that the predictions apply equally well to much larger mesoscopic coherent conductors [16][17]. A requirement of impact of the nonconservative force is that two or more vibrational modes close in frequency couple to each other via the current carrying electronic states. This can establish a generalized

Probing the local environment of a single OPE3 molecule using inelastic tunneling electron spectroscopy

• Riccardo Frisenda,
• Mickael L. Perrin and
• Herre S. J. van der Zant

Beilstein J. Nanotechnol. 2015, 6, 2477–2484, doi:10.3762/bjnano.6.257

• the vibrational modes which constitute a chemical fingerprint of the molecule. In addition, changes can be attributed to rearrangements of the local molecular environment, in particular at the molecule–electrode interface. This study shows the importance of taking into account the interaction with the

• electrodes when describing inelastic contributions to transport through single-molecule junctions. Keywords: current–voltage characteristics; DFT calculations; mechanically controllable break junction (MCBJ); molecule–electrode interaction; vibrational modes; Introduction Vibrational degrees of freedom in

• quantum chemistry calculations for different junction geometries allows for identifying some of the vibrational modes contributing to transport. Our findings suggest that the different junction configurations are characterized by differences in the molecule–electrode interface. Results In our

Surface-enhanced Raman scattering by colloidal CdSe nanocrystal submonolayers fabricated by the Langmuir–Blodgett technique

• Alexander G. Milekhin,
• Larisa L. Sveshnikova,
• Tatyana A. Duda,
• Ekaterina E. Rodyakina,
• Volodymyr M. Dzhagan,
• Ovidiu D. Gordan,
• Sergey L. Veber,
• Cameliu Himcinschi,
• Alexander V. Latyshev and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2015, 6, 2388–2395, doi:10.3762/bjnano.6.245

• substances [2][3][4][5][6][7] down to a single molecule [8][9]. The primary benefit of SERS is that the intensity of Raman scattering by vibrational modes in molecules is drastically increased (typically by a factor of 105–106) when the molecules are placed in the proximity of noble metal nanoclusters or on

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

• displayed in Figure 4 confirm the impact of the plasma fluorination on the vibrational modes of the pristine sample. This technique is often used for a qualitative investigation of the functionalization effect on carbon nanotubes structures [2][44][45][46][47] and to quantify the defect density in the CNTs

Au nanoparticle-based sensor for apomorphine detection in plasma

• Chiara Zanchi,
• Andrea Lucotti,
• Matteo Tommasini,
• Sebastiano Trusso,
• Ugo de Grazia,
• Emilio Ciusani and
• Paolo M. Ossi

Beilstein J. Nanotechnol. 2015, 6, 2224–2232, doi:10.3762/bjnano.6.228

• and theoretical investigations [30]. The closeness of the molecule to the nanostructured metal surface is an inherent condition for SERS enhancement. Therefore, the assignment of experimental peaks to specific vibrational modes of the analyte is important to understand the kind of interaction between

A single-source precursor route to anisotropic halogen-doped zinc oxide particles as a promising candidate for new transparent conducting oxide materials

• Daniela Lehr,
• Markus R. Wagner,
• Johanna Flock,
• Julian S. Reparaz,
• Clivia M. Sotomayor Torres,
• Alexander Klaiber,
• Thomas Dekorsy and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2015, 6, 2161–2172, doi:10.3762/bjnano.6.222

• lattice strain [76]. The LO mode can interact with electrons from the conduction band, the magnitude depends on the free carrier distribution [77][78]. The Raman spectra shown in Figure 5 are dominated by the characteristic vibrational modes E2low at about 98 cm−1 and E2high at about 439 cm−1 [79]. The

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

• continuous. The frequency spectrum of the total ionic kinetic energy (for all N ions) is then where {An(ω)} is a Fourier component of {Rn(t)}. The window is then moved along in time. Results and Discussion Landauer steady-state calculations First we analyse the equilibrium vibrational modes determined from

Thermoelectricity in molecular junctions with harmonic and anharmonic modes

• Bijay Kumar Agarwalla,
• Jian-Hua Jiang and
• Dvira Segal

Beilstein J. Nanotechnol. 2015, 6, 2129–2139, doi:10.3762/bjnano.6.218

• bias voltage [6][7][8]. The system is also referred to as the “dimer molecular junction” [9], or an “open spin–boson model” [10] (where the spin here represents the D and A states, the bosons correspond to the molecular vibrational modes, and the system is open, i.e., coupled to metal leads). It was

• coefficients reveal on molecular junctions? Specifically, can they expose the underlying electron–phonon interactions and the characteristics of the vibrational modes participating in the process? Focusing on the challenge of efficient thermoelectric systems, how should we tune molecular parameters to improve

• transport characteristics across the junction, mediated by molecular vibrational modes. Consideration of the phononic thermal conductance κph is particularly important for a reliable estimate of ZT, as the thermal conductance Σ should include contributions from both electrons and phonons. We now estimate

The role of low-energy electrons in focused electron beam induced deposition: four case studies of representative precursors

• Rachel M. Thorman,
• Ragesh Kumar T. P.,
• D. Howard Fairbrother and
• Oddur Ingólfsson

Beilstein J. Nanotechnol. 2015, 6, 1904–1926, doi:10.3762/bjnano.6.194

• the chemical composition of the remaining film was probed by XPS, HREELS was used to study the change in vibrational modes of the adsorbed molecules. Figure 15 shows a time-resolved mass spectrum monitoring the PF3 desorption during electron exposure after an initial electron dose of 0, 1.5 × 1014

Large-voltage behavior of charge transport characteristics in nanosystems with weak electron–vibration coupling

• Tomáš Novotný and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2015, 6, 1853–1859, doi:10.3762/bjnano.6.188

• physical arguments and classical master equation description of the vibration mode. We find that for the undamped vibrational modes mutual dynamical interplay between electronic and vibronic degrees of freedom leads to strongly nonlinear (in voltage) transport characteristics of the nanosystem. In

• particular, we find that for large voltages the k-th cumulant of the current grows as V2k to be contrasted with the linear dependence in case of more strongly externally damped and thus thermalized vibrational modes. Keywords: electron-vibration interaction; full counting statistics; large-voltage behavior

• method called the lowest order expansion (LOE) was developed [12][13][14]. In its original form LOE only works under the assumption of (externally) equilibrated vibrational modes. While this assumption is often satisfied, there are many other cases when it is broken, e.g., in one of the pioneering

Imaging of carbon nanomembranes with helium ion microscopy

• André Beyer,
• Henning Vieker,
• Robin Klett,
• Hanno Meyer zu Theenhausen,
• Polina Angelova and
• Armin Gölzhäuser

Beilstein J. Nanotechnol. 2015, 6, 1712–1720, doi:10.3762/bjnano.6.175

• other suitable indicators that are detectable by optical microscopy. In addition, optical imaging with a Mirau interferometer allows the detection of the vibrational modes of bare CNMs with a resolution limited by the light wavelength [15]. The imaging of CNMs with higher magnification requires charged

Entropy effects in the collective dynamic behavior of alkyl monolayers tethered to Si(111)

• Christian Godet

Beilstein J. Nanotechnol. 2015, 6, 583–594, doi:10.3762/bjnano.6.60

• the dipole reorientation path with the molecular vibrational modes and manifest a collective dynamic response. Trans–gauche isomerization Over the whole investigated temperature range, the strength of relaxation peak B1 is remarkably stable (Figure 7), as expected for a constant number of carboxylic

• excitations available from the thermal bath (divided by a number of the order of 1). Hence, as |VDC| increases, increasingly large number of vibrational excitations (in the range of 10–50) is required to overcome the activation barrier for collective molecular reorientation. Coupling with vibrational modes

SERS and DFT study of copper surfaces coated with corrosion inhibitor

• Maurizio Muniz-Miranda,
• Francesco Muniz-Miranda and
• Stefano Caporali

Beilstein J. Nanotechnol. 2014, 5, 2489–2497, doi:10.3762/bjnano.5.258

• tautomer, along with the vibrational modes corresponding to the strongest Raman bands, are shown in Figure 5. The N2–C3 and N4–C5 bonds are the shortest double bonds according to the experimental structure [22][23]. In general, the calculated distances are very similar to the experimental values, which

• (profilometry) of an etched copper surface. Total scan length 4.8 mm. Normal FT-Raman spectra of 1,2,4-triazole in solution. Solvent subtracted. Optimized geometry of 1H-1,2,4-triazole (upper left) with the calculated distances (angstroms), along with the vibrational modes corresponding to the strongest Raman

Localized surface plasmon resonances in nanostructures to enhance nonlinear vibrational spectroscopies: towards an astonishing molecular sensitivity

• Dan Lis and
• Francesca Cecchet

Beilstein J. Nanotechnol. 2014, 5, 2275–2292, doi:10.3762/bjnano.5.237

• only a limited fraction of the chemisorbed molecules was precisely located at the nanosphere junctions, thereby estimating the local enhancement factor to range from 104 to 106. It is interesting to notice that for both gold and silver coating, the SFG vibrational modes appeared as clear peaks when

• ). Note that a 12 µm pyridine sample did not provide any measurable CARS signal (green trace in Figure 11a). The spectra showed three vibrational modes of the free and H-bonded pyridine–water complexes. Basically, the authors used femtosecond pump and Stokes laser pulses with frequencies matching the

The influence of molecular mobility on the properties of networks of gold nanoparticles and organic ligands

• Edwin J. Devid,
• Paulo N. Martinho,
• M. Venkata Kamalakar,
• Úna Prendergast,
• Christian Kübel,
• Tibebe Lemma,
• Jean-François Dayen,
• Tia. E. Keyes,
• Bernard Doudin,
• Mario Ruben and
• Sense Jan van der Molen

Beilstein J. Nanotechnol. 2014, 5, 1664–1674, doi:10.3762/bjnano.5.177

• molecules experienced in the array compared to the powder. Furthermore, the SERS spectrum is less complex than that of the powder. This is consistent with plasmonic enhancement as the vibrational modes involving the atoms closest to the gold nanoparticle will be selectively enhanced. Whereas the low

Hole-mask colloidal nanolithography combined with tilted-angle-rotation evaporation: A versatile method for fabrication of low-cost and large-area complex plasmonic nanostructures and metamaterials

• Jun Zhao,
• Bettina Frank,
• Frank Neubrech,
• Chunjie Zhang,
• Paul V. Braun and
• Harald Giessen

Beilstein J. Nanotechnol. 2014, 5, 577–586, doi:10.3762/bjnano.5.68

• -range. As shown in Figure 5b, the SRR plasmon resonance, as well as the two vibrational modes of the d-ODT molecule is nearly the same for all the measurements. This experiment verifies the extremely homogeneous arrangement of the SRR structures over large-area with really low defect concentration

Challenges in realizing ultraflat materials surfaces

• Takashi Yatsui,
• Wataru Nomura,
• Fabrice Stehlin,
• Olivier Soppera,
• Makoto Naruse and
• Motoichi Ohtsu

Beilstein J. Nanotechnol. 2013, 4, 875–885, doi:10.3762/bjnano.4.99

• generated at the surface of an illuminated nanoscale particle, its energy can be exchanged with this crystal lattice. Through this exchange, vibrational modes can be coherently excited in the crystal lattice, creating multiple modes of coherent phonon states [22]. Consequently, the DP and a coherent phonon

• form a coupled state (Figure 1a). This state (the dressed photon and a phonon: DPP) constitutes a quasi-particle that is generated only when the particle size is sufficiently small so that the crystal lattice vibration is excited coherently. In contrast, vibrational modes cannot be excited coherently

Probing the plasmonic near-field by one- and two-photon excited surface enhanced Raman scattering

• Katrin Kneipp and
• Harald Kneipp

Beilstein J. Nanotechnol. 2013, 4, 834–842, doi:10.3762/bjnano.4.94

• , particularly for higher frequency vibrational modes. However, the situation can be dramatically changed in a very strong surface-enhanced Raman process. This is illustrated in Figure 2: Isolated silver or gold nanoparticles support a surface-enhanced Raman signal of crystal violet shown in the Stokes spectrum

Size variation of infrared vibrational spectra from molecules to hydrogenated diamond nanocrystals: a density functional theory study

• Mudar A. Abdulsattar

Beilstein J. Nanotechnol. 2013, 4, 262–268, doi:10.3762/bjnano.4.28

• region are C–C vibrations. The reduced mass formula of two particles of masses ma and mb is given by: Although the above equation is for diatomic molecules, it can be used for the understanding of vibrational modes of other larger molecules. We can note from the above equation that the reduced mass of

Functionalised zinc oxide nanowire gas sensors: Enhanced NO₂ gas sensor response by chemical modification of nanowire surfaces

• Eric R. Waclawik,
• Jin Chang,
• Andrea Ponzoni,
• Isabella Concina,
• Dario Zappa,
• Elisabetta Comini,
• Nunzio Motta,
• Guido Faglia and
• Giorgio Sberveglieri

Beilstein J. Nanotechnol. 2012, 3, 368–377, doi:10.3762/bjnano.3.43

• from the dodecanethiol C–H symmetric and asymmetric stretch vibrational modes can be clearly seen at 2850 and 2920 cm−1, respectively, which indicates that functionalisation of ZnO by DT in this way was successful. The dodecanethiol peaks were completely absent in the pure ZnO FTIR spectrum of Figure 3

Current-induced forces in mesoscopic systems: A scattering-matrix approach

• Niels Bode,
• Silvia Viola Kusminskiy,
• Reinhold Egger and
• Felix von Oppen

Beilstein J. Nanotechnol. 2012, 3, 144–162, doi:10.3762/bjnano.3.15

• vibrational modes on the electronic dynamics. We employ the scattering-matrix approach to quantum transport in order to develop a unified theory of nanoelectromechanical systems out of equilibrium. For a slow mechanical mode the current can be obtained from the Landauer–Büttiker formula in the strictly

• –Condon blockade effect, a phononic analogue of the Coulomb blockade in quantum dots [25][26][27]. In the opposite regime, electrons tunnel through the nanostructure rapidly, observing a quasistatic configuration of the vibrational modes, but affecting their dynamics profoundly at the same time [18][19

• limit, it is natural to assume that the dynamics of the vibrational modes, represented by collective coordinates Xν, will be governed by a set of coupled Langevin equations Here we have grouped the purely elastic contribution on the left-hand side (LHS) of Equation 1, Mν being the effective mass of mode

Current-induced dynamics in carbon atomic contacts

• Jing-Tao Lü,
• Tue Gunst,
• Per Hedegård and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2011, 2, 814–823, doi:10.3762/bjnano.2.90

• obtained temperature distributions with (Figure 6c, Figure 6d) and without (Figure 6e, Figure 6f) the anharmonic interactions shows that anharmonic couplings between the vibrational modes have a significant influence on the heat-transport properties and local Joule heating of the system. The heating is

Interaction of spin and vibrations in transport through single-molecule magnets

• Falk May,
• Maarten R. Wegewijs and
• Walter Hofstetter

Beilstein J. Nanotechnol. 2011, 2, 693–698, doi:10.3762/bjnano.2.75

• )D for E = 0 (and E′ = D′ = 0). The transverse anisotropy E breaks the continuous rotational symmetry about the easy-axis of the SMM, thereby causing spin-tunneling through the barrier. As shown in [9], vibrational modes modulate the magnetic anisotropy and can significantly contribute to the

Towards multiple readout application of plasmonic arrays

• Dana Cialla,
• Karina Weber,
• René Böhme,
• Uwe Hübner,
• Henrik Schneidewind,
• Matthias Zeisberger,
• Roland Mattheis,
• Robert Möller and
• Jürgen Popp

Beilstein J. Nanotechnol. 2011, 2, 501–508, doi:10.3762/bjnano.2.54

• spectrum of the fluorescence reporter molecules prevents the parallel detection of several fluorescent dye labels by fluorescence microscopy. Raman spectroscopy, i.e., the excitation of vibrational modes through inelastic light scattering, allows one to obtain highly specific molecular fingerprint

Towards a scalable and accurate quantum approach for describing vibrations of molecule–metal interfaces

• David M. Benoit,
• Bruno Madebene,
• Inga Ulusoy,
• Luis Mancera,
• Yohann Scribano and
• Sergey Chulkov

Beilstein J. Nanotechnol. 2011, 2, 427–447, doi:10.3762/bjnano.2.48

• structure calculations of decreasing accuracy [13][14] and have achieved reasonable accuracy for small to medium-sized molecules. The fast-VSCF technique uses the fact that there are preferred channels along which vibrational modes interact with each other and that these channels dominate the vibrational

• vibrational basis than does a basis of uncoupled harmonic oscillators. The size of the virtual configuration basis set can be controlled by a threshold parameter that limits the excitation of each quanta and/or the sum of quanta over all vibrational modes. The term “virtual” indicates that all excited modal