A simple and efficient quasi 3-dimensional viscoelastic model and software for simulation of tapping-mode atomic force microscopy

• Santiago D. Solares

Beilstein J. Nanotechnol. 2015, 6, 2233–2241, doi:10.3762/bjnano.6.229

• shortcomings. The first shortcoming derives directly from its simplicity and computational efficiency: since the individual SLS elements do not interact with one another, the model does not consider material relaxations in the horizontal directions. As a result, it cannot be used as a ‘first-principles

Controlled switching of single-molecule junctions by mechanical motion of a phenyl ring

• Yuya Kitaguchi,
• Satoru Habuka,
• Hiroshi Okuyama,
• Shinichiro Hatta,
• Tetsuya Aruga,
• Thomas Frederiksen,
• Magnus Paulsson and
• Hiromu Ueba

Beilstein J. Nanotechnol. 2015, 6, 2088–2095, doi:10.3762/bjnano.6.213

• was studied by first-principles simulations, revealing the relative stabilities of the flat and lifted molecular configurations. Finite-bias calculations showed consistency with the observed tendency for the junction to prefer the on (off) state at negative (positive) sample voltages. The low-bias

High I_on/I_off current ratio graphene field effect transistor: the role of line defect

• Mohammad Hadi Tajarrod and
• Hassan Rasooli Saghai

Beilstein J. Nanotechnol. 2015, 6, 2062–2068, doi:10.3762/bjnano.6.210

• electrical structure of the transistor channel, which conformed to the first-principles calculations used to describe the electronic band structure of ELD-AGNRs [19][20]. The Hamiltonian computation in this system was separated into AGNR (HA), line defect (HD) and coupling between AGNR and the defect (HC

Atomic scale interface design and characterisation

• Carla Bittencourt,
• Chris Ewels and
• Arkady V. Krasheninnikov

Beilstein J. Nanotechnol. 2015, 6, 1708–1711, doi:10.3762/bjnano.6.174

• , France Department of Applied Physics, Aalto University, Finland Institute of Ion Beam Physics and Materials Research, Helmholtz Zentrum Dresden-Rossendorf, Germany 10.3762/bjnano.6.174 Keywords: carbon; first-principles simulations; interface; nanomaterials; nanoscale; oxides; spectromicroscopy; While

• better than 0.1 nm, in addition to elemental analysis [25]. The analysis of experimental results can significantly profit from the comparison of the images to the results of first-principles calculations. Similarly, for the precise interpretation of experimental scanning tunneling microscopy (STM) and

• atomic force microscopy (AFM) images, the microscopy knowledge about the local electronic structure of the system is extremely important. Full understanding of the electronic structure and properties of a large number of solids can be credited to first principles simulations, and more specifically

Simple and efficient way of speeding up transmission calculations with k-point sampling

• Jesper Toft Falkenberg and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2015, 6, 1603–1608, doi:10.3762/bjnano.6.164

• ” first principles calculations where the leads/electrodes are described by periodic boundary conditions. We show examples of transport in graphene structures where a speed-up of an order of magnitude is easily obtained. Keywords: density functional theory; electronic conductance; interpolation; post

• scheme and conclude in section Conclusion. Results and Discussion Description of the method The use of computationally “expensive” first principles DFT-NEGF calculations for determining the transmission through nano-structured systems is limited by the amount of time one can afford to spend on the k-grid

Possibilities and limitations of advanced transmission electron microscopy for carbon-based nanomaterials

• Xiaoxing Ke,
• Carla Bittencourt and
• Gustaaf Van Tendeloo

Beilstein J. Nanotechnol. 2015, 6, 1541–1557, doi:10.3762/bjnano.6.158

• suggests a C–N bond [94]. Together with the help of first principles calculations, STEM–EELS further reveals the configurations of single N-substitutions in SWCNT as graphitic and pyrrolic [95]. A more striking result is reported in Si-doped graphene [96], in which a sp3-like trivalent Si substitute and a

Enhanced fullerene–Au(111) coupling in (2√3 × 2√3)R30° superstructures with intermolecular interactions

• Michael Paßens,
• Rainer Waser and
• Silvia Karthäuser

Beilstein J. Nanotechnol. 2015, 6, 1421–1431, doi:10.3762/bjnano.6.147

• to the C60 marked with a blue circle in Figure 4d. This scenario is promoted by a first-principles study of C60 on a Pt(111) surface [40]. Here, it was concluded that Pt adatoms resulting from vacancy–adatom formation are located in the interstitial regions between the C60 molecules on the Pt(111

Electronic interaction in composites of a conjugated polymer and carbon nanotubes: first-principles calculation and photophysical approaches

• Florian Massuyeau,
• Jany Wéry,
• Jean-Luc Duvail,
• Serge Lefrant,
• Abu Yaya,
• Chris Ewels and
• Eric Faulques

Beilstein J. Nanotechnol. 2015, 6, 1138–1144, doi:10.3762/bjnano.6.115

• density functional theory (DFT) calculations of coupling effects between the polymer and both species of SWNTs. Combined experimental results and first-principles calculations provide evidence that significant electronic interaction can take place between PPV chains and semiconducting SWNTs while metallic

Electrocatalysis on the nm scale

• R. Jürgen Behm

Beilstein J. Nanotechnol. 2015, 6, 1008–1009, doi:10.3762/bjnano.6.103

• developed to a stage where a reliable description of complex surface structures and surface processes (at the solid–gas interface) is possible based on first-principles electronic structure theory (in particular, (periodic) density functional theory (DFT)), but it is also increasingly developing new

• approaches for a more realistic modeling of the electrochemical solid–liquid interface from first principles. Although there is still a long way to go, it is not unrealistic to assume that an atomic/molecular scale understanding of the elementary processes occurring at the electrochemical interface (similar

Raman spectroscopy as a tool to investigate the structure and electronic properties of carbon-atom wires

• Alberto Milani,
• Matteo Tommasini,
• Valeria Russo,
• Andrea Li Bassi,
• Andrea Lucotti,
• Franco Cataldo and
• Carlo S. Casari

Beilstein J. Nanotechnol. 2015, 6, 480–491, doi:10.3762/bjnano.6.49

• ., determination of wire length). Moreover, by employing Raman spectroscopy and surface enhanced Raman scattering in combination with the support of first principles calculations, we show that a detailed understanding of the charge transfer between CAWs and metal nanoparticles may open the possibility to tune the

• wavelengths with the support of first principles calculations will be reviewed. We begin by discussing the structure of ideal and as-synthesized CAWs with particular focus on π-conjugation effects and the change in electronic properties as a result of the wire length and termination. Then we review the

• ), which have been discussed in detail in [32] through theoretical analysis and first-principles calculations. This spectral region is particular to sp carbon, since none of the other carbon nanostructures have peaks in this region (see Figure 3). Within this spectral region cumulenes exhibit lower overall

Nanoparticle shapes by using Wulff constructions and first-principles calculations

• Georgios D. Barmparis,
• Zbigniew Lodziana,
• Nuria Lopez and
• Ioannis N. Remediakis

Beilstein J. Nanotechnol. 2015, 6, 361–368, doi:10.3762/bjnano.6.35

• shapes and habits found in mineral crystals. Near the end of the twentieth century, Wulff construction was re-discovered in materials science and was used to characterize shapes of nanoparticles. Today, multi-scale simulations that use Wulff constructions based on first-principles quantum-mechanical

• structure of materials allowed for calculations of interface tensions from first principles. These data were often used in Wulff constructions for the prediction of the shape of nanoparticles in a variety of environments. Some characteristic examples include supported Au [33][34], diamond [35], TiO2 [36

• ammonia-synthesis catalyst from first principles [47][48][49]. Density functional calculations were used to obtain accurate surface energies for several faces of hcp Ru. These values were used in a standard Wulff-construction software to create the polyhedron that corresponded to the equilibrium shape. In

Carrier multiplication in silicon nanocrystals: ab initio results

• Ivan Marri,
• Marco Govoni and
• Stefano Ossicini

Beilstein J. Nanotechnol. 2015, 6, 343–352, doi:10.3762/bjnano.6.33

• the recorded PL and IA signals. In this work, we investigate effects induced on CM dynamics using first principles calculations. One-site CM, Coulomb-driven charge transfer (CDCT) and SSQC processes are evaluated in detail and a hierarchy of CM lifetimes are noted. Theory In this work we investigate

• -NCs were investigated for the first time by first-principles calculations by Govoni et al. [31], who simulated CM decays in systems of isolated and interacting Si-NCs. CM lifetimes were calculated in four different spherical and hydrogenated systems, that is the Si35H36 ( = 3.42 eV, 1.3 nm of diameter

• potential (and by local fields) was then clarified. The effects induced by NC interplay on CM dynamics have been investigated considering a system formed by two NCs placed in close proximity, that is, Si87H76 × Si293H172. One-site CM, SSQC and CDCT lifetimes have been quantified by first principles

Silicon and germanium nanocrystals: properties and characterization

• Ivana Capan,
• Alexandra Carvalho and
• José Coutinho

Beilstein J. Nanotechnol. 2014, 5, 1787–1794, doi:10.3762/bjnano.5.189

• to solve by first-principles the all-electron problem of systems with a few thousands of atoms [17]. This has led to the understanding of more complex problems such as doping [18][19][20], and electronic transport across NC solids [21][22]. These are among the advances that will be reviewed below. II

• MBE. From the experimental point of view, the synthesis of free-standing NCs will not be covered within this review. However, those issues are visited in Section III of this paper, which deals with the first principles modelling of the NCs. II.1 Magnetron co-sputtering This is basically a technique

• understand the trends found by experimental and atomistic modeling studies. More recently, significant understanding of the relationships between structure, chemistry and electronic structure has been obtained from first-principles calculations based on density functional theory. From a theoretical

Quasi-1D physics in metal-organic frameworks: MIL-47(V) from first principles

• Danny E. P. Vanpoucke,
• Jan W. Jaeken,
• Stijn De Baerdemacker,
• Kurt Lejaeghere and
• Veronique Van Speybroeck

Beilstein J. Nanotechnol. 2014, 5, 1738–1748, doi:10.3762/bjnano.5.184

• electronic structure of MIL-47(V) is investigated by using first principles calculations. An antiferromagnetic ground state is found, consisting of antiferromagnetic chains with an antiferromagnetic inter-chain coupling. This supports the experimental assumption of such a ground state favored over an

Restructuring of an Ir(210) electrode surface by potential cycling

• Khaled A. Soliman,
• Dieter M. Kolb,
• Ludwig A. Kibler and
• Timo Jacob

Beilstein J. Nanotechnol. 2014, 5, 1349–1356, doi:10.3762/bjnano.5.148

• in- and outside a UHV chamber. It was found that the presence of oxygen is crucial for the faceting process on Ir(210) [21][22]. Theoretical calculations for the Ir(210) system, based on first principles, provided supportive information. It was shown that, due to the anisotropy in surface free energy

Magnesium batteries: Current state of the art, issues and future perspectives

• Rana Mohtadi and
• Fuminori Mizuno

Beilstein J. Nanotechnol. 2014, 5, 1291–1311, doi:10.3762/bjnano.5.143

• . [53] studied the possibility of magnesium ion conduction in the high temperature phase of magnesium borohydride using first-principles molecular dynamics simulations FPMD [53][54]. The magnesium ions, present in the center of a tetrahedral cage surrounded by the BH4− anions, were found to have limited

• study of borohydride-based solid state electrolytes was reported by Higashi et al. [37]. Guided by their first-principles calculations based on density functional theory (DFT), they experimentally investigated the conduction of magnesium ions in both Mg(BH4)2 and Mg(BH4)(NH2). The selection of these

Fringe structures and tunable bandgap width of 2D boron nitride nanosheets

• Peter Feng,
• Muhammad Sajjad,
• Eric Yiming Li,
• Hongxin Zhang,
• Jin Chu,
• Ali Aldalbahi and
• Gerardo Morell

Beilstein J. Nanotechnol. 2014, 5, 1186–1192, doi:10.3762/bjnano.5.130

• gap (which was computed to be 4.29 eV in pristine BNNT) decreased to 2.01 eV [11]. For BNNSs case the adsorption behavior of a single H atom either on the top site of a B or on the top site of an N atom, or two H atoms adsorbed on adjacent B and N sites are also investigated [12]. Using first

• -principles computations [13] and hybrid density functional theory calculations with van der Waals correction [14], Chen and Zhang show that polar boron nitride (BN) nanoribbons can be favorably aligned via substantial hydrogen bonding at the interfaces, which induces significant interface polarizations and

Neutral and charged boron-doped fullerenes for CO₂ adsorption

• Suchitra W. de Silva,
• Aijun Du,
• Wijitha Senadeera and
• Yuantong Gu

Beilstein J. Nanotechnol. 2014, 5, 413–418, doi:10.3762/bjnano.5.49

• . Computational Details First-principles density functional theory (DFT) calculations were carried out to study CO2 adsorption on the BC59 cage. The BC59 structure was fully optimized in the given symmetry. The calculations were carried out at B3LYP [20][21][22] level of theory while using the split valance

Quantum size effects in TiO₂ thin films grown by atomic layer deposition

• Massimo Tallarida,
• Chittaranjan Das and
• Dieter Schmeisser

Beilstein J. Nanotechnol. 2014, 5, 77–82, doi:10.3762/bjnano.5.7

• , the spectral features observed for very thin TiO2 films were addressed to a decreased ligand-field at TiO2/substrate interfaces, which was found to be increasingly important when moving from the MgO substrate to SiO2 [21]. Instead, Krüger used a first-principles multichannel multiple-scattering

Many-body effects in semiconducting single-wall silicon nanotubes

• Wei Wei and
• Timo Jacob

Beilstein J. Nanotechnol. 2014, 5, 19–25, doi:10.3762/bjnano.5.2

• nature, and the envelope function in the case of (10,0) SiNT. Conclusion In summary, electronic and optical properties of single-wall semiconducting SiNTs have been studied by means of first-principles many-body perturbation theory. It has been elucidated that many-body effects strongly depend on the

Large-scale atomistic and quantum-mechanical simulations of a Nafion membrane: Morphology, proton solvation and charge transport

• Pavel V. Komarov,
• Pavel G. Khalatur and
• Alexei R. Khokhlov

Beilstein J. Nanotechnol. 2013, 4, 567–587, doi:10.3762/bjnano.4.65

• Department, Moscow State University, Moscow 119991, Russia 10.3762/bjnano.4.65 Abstract Atomistic and first-principles molecular dynamics simulations are employed to investigate the structure formation in a hydrated Nafion membrane and the solvation and transport of protons in the water channel of the

• PEFCs [54][55][56][57][58][59]. There are excellent reviews that cover this subject in considerable detail [5][12][60]. In this paper, the atomistic and first-principles molecular dynamics simulations are employed to investigate the structure formation in hydrated Nafion membrane and the solvation and

Magnetic anisotropy of graphene quantum dots decorated with a ruthenium adatom

• Igor Beljakov,
• Velimir Meded,
• Franz Symalla,
• Karin Fink,
• Sam Shallcross and
• Wolfgang Wenzel

Beilstein J. Nanotechnol. 2013, 4, 441–445, doi:10.3762/bjnano.4.51

• of the flake. Conclusion Using first-principles DFT methods we have investigated the magnetic properties of Ru adatoms on two types of graphene flakes: the armchair (AGQD) and zigzag (ZGQD) edged triangular graphene quantum dots. The geometry of these flakes is such that each has only one specific

Influence of the solvent on the stability of bis(terpyridine) structures on graphite

• Daniela Künzel and
• Axel Groß

Beilstein J. Nanotechnol. 2013, 4, 269–277, doi:10.3762/bjnano.4.29

• of the considered systems and the requirement to perform thermal averages make first-principles electronic-structure calculations computationally prohibitively expensive. Therefore we employed classical force fields as included in the Forcite module of the Accelrys’ Materials Studio package to

Electronic and transport properties of kinked graphene

• Jesper Toft Rasmussen,
• Tue Gunst,
• Peter Bøggild,
• Antti-Pekka Jauho and
• Mads Brandbyge

Beilstein J. Nanotechnol. 2013, 4, 103–110, doi:10.3762/bjnano.4.12

• bending, of a graphene sheet is known to increase the chemical reactivity presenting an opportunity for templated chemical functionalisation. Using first-principles calculations based on density functional theory (DFT), we investigate the reaction barrier reduction for the adsorption of atomic hydrogen at

Towards atomic resolution in sodium titanate nanotubes using near-edge X-ray-absorption fine-structure spectromicroscopy combined with multichannel multiple-scattering calculations

• Carla Bittencourt,
• Peter Krüger,
• Maureen J. Lagos,
• Xiaoxing Ke,
• Gustaaf Van Tendeloo,
• Chris Ewels,
• Polona Umek and
• Peter Guttmann

Beilstein J. Nanotechnol. 2012, 3, 789–797, doi:10.3762/bjnano.3.88

• resolution in similar techniques with lower spectral resolution [9][10]. We investigate here the electronic structure of sodium titanate nanotubes ((Na,H)TiNTs) by means of near-edge X-ray-absorption fine-structure spectroscopy (NEXAFS) coupled with first-principles NEXAFS calculations (density functional