Surface excitations in the modelling of electron transport for electron-beam-induced deposition experiments

• Francesc Salvat-Pujol,
• Roser Valentí and
• Wolfgang S. Werner

Beilstein J. Nanotechnol. 2015, 6, 1260–1267, doi:10.3762/bjnano.6.129

• obtained experimentally [33] or from theoretical calculations, e.g., via density-functional theory calculations [33][34][35]. An ω-dependent dielectric function is sufficient to describe the response of the medium to a spatially homogeneous perturbation, such as that of an incoming photon. However, for

Two-dimensional and tubular structures of misfit compounds: Structural and electronic properties

• Tommy Lorenz,
• Jan-Ole Joswig and
• Gotthard Seifert

Beilstein J. Nanotechnol. 2014, 5, 2171–2178, doi:10.3762/bjnano.5.226

• electronic structure has been predicted by density functional theory calculations using the generalized gradient approximation. From the overlap of the empty bands in NbS2 with the filled valence band of PbSe, the authors concluded that “only a small fraction of an electron’s charge is transferred per atom

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

• Density functional theory calculations Density functional theory (DFT) calculations are performed within the projector augmented wave (PAW) method as implemented in the “Vienna ab initio Simulation Package” (VASP) while using the generalized gradient approximation (GGA) functional as constructed by Perdew

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

• for the different Ir surface orientations, the adsorption of more than 0.5 ML oxygen causes the formation of nano-pyramids exhibiting (110) and {311} faces to be thermodynamically more stable than the original Ir(210) substrate [19][23]. Based on density functional theory calculations it was predicted

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

• -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

Organic and inorganic–organic thin film structures by molecular layer deposition: A review

• Pia Sundberg and
• Maarit Karppinen

Beilstein J. Nanotechnol. 2014, 5, 1104–1136, doi:10.3762/bjnano.5.123

• +ED molecule length of 12.6 Å, and also below the somewhat lower GPC value of 6.5 Å per cycle expected based on the density functional theory calculations carried out by the group. The film growth was observed to be linear. The films were stable in ambient air and when annealed at least up to 250 °C

Uncertainties in forces extracted from non-contact atomic force microscopy measurements by fitting of long-range background forces

• Adam Sweetman and
• Andrew Stannard

Beilstein J. Nanotechnol. 2014, 5, 386–393, doi:10.3762/bjnano.5.45

• electrostatic forces. Typically, the contribution from these forces must be removed before the results of the experiment can be successfully interpreted, often by comparison to density functional theory calculations. In this paper we compare the ‘on-minus-off’ method for extracting site-specific forces to a

The role of oxygen and water on molybdenum nanoclusters for electro catalytic ammonia production

• Jakob G. Howalt and
• Tejs Vegge

Beilstein J. Nanotechnol. 2014, 5, 111–120, doi:10.3762/bjnano.5.11

• to reach the catalyst surface. Small amounts of oxygen present at the molybdenum nanocluster surface, arising from either the electrolyte or from the preparation of the electrocatalyst, should therefore not affect the electrochemical production of ammonia. Conclusion Density functional theory

• , we present theoretical investigations of the influence of oxygen adsorption and reduction on pure and nitrogen covered molybdenum nanocluster electro catalysts for electrochemical reduction of N2 to NH3 with the purpose of understanding oxygen and water poisoning of the catalyst. Density functional

• theory calculations are used in combination with the computational hydrogen electrode approach to calculate the free energy profile for electrochemical protonation of O and N2 species on cuboctahedral Mo13 nanoclusters. The calculations show that the molybdenum nanocluster will preferentially bind oxygen

Adsorption of the ionic liquid [BMP][TFSA] on Au(111) and Ag(111): substrate effects on the structure formation investigated by STM

• Benedikt Uhl,
• Florian Buchner,
• Dorothea Alwast,
• Nadja Wagner and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2013, 4, 903–918, doi:10.3762/bjnano.4.102

• reconstruction plays a major role in the structure formation of the 2D crystalline phase. In combination with recent density functional theory calculations, the sub-molecularly resolved STM images allow to clearly discriminate between the [BMP]+ cation and [TFSA]− anion. Keywords: adsorption; Ag; Au; [BMP][TFSA

Photoresponse from single upright-standing ZnO nanorods explored by photoconductive AFM

• Igor Beinik,
• Markus Kratzer,
• Astrid Wachauer,
• Lin Wang,
• Yuri P. Piryatinski,
• Gerhard Brauer,
• Xin Yi Chen,
• Yuk Fan Hsu,
• Aleksandra B. Djurišić and
• Christian Teichert

Beilstein J. Nanotechnol. 2013, 4, 208–217, doi:10.3762/bjnano.4.21

• conditions originates preferentially from photoexcitation of charge carriers localized at defect states and dominates over the oxygen photodesorption mechanism. Our findings are in agreement with previous theoretical predictions based on density functional theory calculations as well as with earlier

• carriers from defect-localized states. The experimental findings are in good agreement with previous theoretical predictions based on density functional theory calculations [42] and will be discussed on the basis of the presence of oxygen vacancies. Experimental ZnO nanorods were grown by thermal

• generation and oxygen desorption, as assumed in the standard model [22]. A theoretical explanation of the persistent photoconductivity in ZnO, which also explains the lowering of the minimum photon energy, has been provided by Lany and Zunger on the basis of density functional theory calculations [42]. The

Structural and electronic properties of oligo- and polythiophenes modified by substituents

• Simon P. Rittmeyer and
• Axel Groß

Beilstein J. Nanotechnol. 2012, 3, 909–919, doi:10.3762/bjnano.3.101

• have been studied by using periodic density functional theory calculations. We have in particular focused on the effect of substituents on the electronic structure of thiophenes. Whereas singly bonded substituents, such as methyl, amino or nitro groups, change the electronic properties of thiophene

• charged polythiophenes demonstrate. Keywords: band gaps; conducting polymers; density functional theory calculations; molecular electronics; oligothiophenes; Introduction Since the first report about the electrical conductivity of doped polyacetylene (PA) in 1977 [1], significant efforts have been spent

• planned for the future. Conclusion The structural and electronic properties of oligo- and polythiophenes and their modifications through substituents have been studied by periodic density functional theory calculations. Whereas the considered oligothiophenes still exhibit nonvanishing dihedral angles, the

Models of the interaction of metal tips with insulating surfaces

• Thomas Trevethan,
• Matthew Watkins and
• Alexander L. Shluger

Beilstein J. Nanotechnol. 2012, 3, 329–335, doi:10.3762/bjnano.3.37

• atomic resolution. Chromium and tungsten tips are used to image the NaCl(001) and MgO(001) surfaces. The interaction of the tips with the surface is simulated by using density-functional-theory calculations employing a mixed Gaussian and plane-wave basis and cluster-tip models. In each case, the apex of

Septipyridines as conformationally controlled substitutes for inaccessible bis(terpyridine)-derived oligopyridines in two-dimensional self-assembly

• Daniel Caterbow,
• Daniela Künzel,
• Michael G. Mavros,
• Axel Groß,
• Katharina Landfester and
• Ulrich Ziener

Beilstein J. Nanotechnol. 2011, 2, 405–415, doi:10.3762/bjnano.2.46

• much more abundant than LinI, whereas for 3,3'-PhSpPy (15) the corresponding densely packed 2D assembly could not be found. With density functional theory calculations, we can show that BTPs and corresponding PhSpPys both possess similar electronic structure. As an example, Figure 8 shows electronic

• Waals contact with van der Waals radii for the H–H contacts of 82.5 pm, as given by the program. Calculations Gaussian 03 [34] density functional theory calculations were carried out with the B3YLP/6-311G [35][36] method. Electrostatic potentials were mapped onto a constant electron density surface. For

Intermolecular vs molecule–substrate interactions: A combined STM and theoretical study of supramolecular phases on graphene/Ru(0001)

• Michael Roos,
• Benedikt Uhl,
• Daniela Künzel,
• Harry E. Hoster,
• Axel Groß and
• R. Jürgen Behm

Beilstein J. Nanotechnol. 2011, 2, 365–373, doi:10.3762/bjnano.2.42

• layer of graphene on top, using a commensurate lattice with a (12 × 12) graphene unit cell on a (11 × 11) Ru(0001) cell with a lattice constant of 29.96 Å, in agreement with experiment, using the coordinates obtained in recent density functional theory calculations from a combined experimental and

Extended X-ray absorption fine structure of bimetallic nanoparticles

• Carolin Antoniak

Beilstein J. Nanotechnol. 2011, 2, 237–251, doi:10.3762/bjnano.2.28

• density functional theory calculations on the magnetic properties. Keywords: bimetallic alloys; EXAFS; FePt; nanoparticles; wavelets; XAS; Introduction Since the discovery of X-rays in 1895 by Röntgen, the field of spectroscopy methods using this regime of the electromagnetic spectrum has reached a very

Structural and magnetic properties of ternary Fe_1–xMn_xPt nanoalloys from first principles

• Markus E. Gruner and
• Peter Entel

Beilstein J. Nanotechnol. 2011, 2, 162–172, doi:10.3762/bjnano.2.20

• the energy related to internal lattice defects, such as twin boundaries, by deliberate design of the alloy composition. This could effectively disfavor multiply twinned morphologies, while the resulting trends can be monitored on the electronic level in the framework of large scale density functional

• theory calculations. At this point, it should be kept in mind that segregated and multiply twinned morphologies may open up other fields of application. Core–shell structures are specially of interest, since enriching the catalytically active material (e. g., Pt or Pd) at the surface may reduce cost

Defects in oxide surfaces studied by atomic force and scanning tunneling microscopy

• Thomas König,
• Georg H. Simon,
• Lars Heinke,
• Leonid Lichtenstein and
• Markus Heyde

Beilstein J. Nanotechnol. 2011, 2, 1–14, doi:10.3762/bjnano.2.1

• aluminum oxide. At these domain boundaries, STS and KPFM verify F2+-like centers, which have been predicted by density functional theory calculations. Thus, by determining the contact potential and the electronic structure with a spatial resolution in the nanometer range, NC-AFM and STM can be successfully

• meV. This shift can be assigned to an F+. For an F+ the overall charge is positive, but on a very local scale the single electron has a probability above the surface as derived by density functional theory calculations [31]. The charge density spills out of the defect’s site and has therefore a