A new method for obtaining model-free viscoelastic material properties from atomic force microscopy experiments using discrete integral transform techniques

• Berkin Uluutku,
• Enrique A. López-Guerra and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2021, 12, 1063–1077, doi:10.3762/bjnano.12.79

• calculations. Specifically, modern computational coding languages use variable precision. For example, for a number that is of order unity, the computational precision is ≈10−16, but for a number that is of order 10100 the precision is ≈1084. Therefore, in calculations with large numbers, one can accumulate a

• Fourier transforms can be found in Supporting Information File 1, Figure S9. (a, d) Amplitude of simulated retardance in the z-domain for an AFM simulation. (b, e) Retardance of the material calculated from the theoretical values. (c, f) Error between the simulation and the theoretical calculations. The

Revealing the formation mechanism and band gap tuning of Sb₂S₃ nanoparticles

• Maximilian Joschko,
• Franck Yvan Fotue Wafo,
• Christina Malsi,
• Danilo Kisić,
• Ivana Validžić and
• Christina Graf

Beilstein J. Nanotechnol. 2021, 12, 1021–1033, doi:10.3762/bjnano.12.76

• can mathematically be treated as a material with an indirect allowed transition. For crystalline Sb2S3, Filip et al. [47] and Vadapoo et al. [48] did first-principle calculations of the band structures. Both found indirect transitions as energetically most favorable but with only a little difference

• direct one in the present work. In contrast, Validžić et al. performed calculations based on the density functional theory and found a direct band gap [31]. The optical data can be seen in Figure 9 and in Figure S9 in Supporting Information File 1. As the spectra of the 2 h, 5 h, and 8 h samples are

Is the Ne operation of the helium ion microscope suitable for electron backscatter diffraction sample preparation?

• Annalena Wolff

Beilstein J. Nanotechnol. 2021, 12, 965–983, doi:10.3762/bjnano.12.73

• to the interaction volume depth. This is referred to as the steady-state condition. The time it takes to mill the sample to that depth and until the steady-state condition is reached determines the maximal area of specific ion implantation concentration. The calculations presented here determine the

• . The darker grains are the slower milling grains [11] which can accumulate a higher Ga impurity concentration according to the calculations above. To verify this, EDS measurements (see Supporting Information File 3) were performed on a Ga irradiated area on slower and faster milling grains. These

• the steady-state condition is reached later, allowing for a higher Ga impurity implantation concentration. The experimental result is in good agreement with the theoretical prediction from the Monte Carlo simulation and subsequent calculations. The Cu3Ga phase-transformed regions are larger for the

Prediction of Co and Ru nanocluster morphology on 2D MoS₂ from interaction energies

• Cara-Lena Nies and
• Michael Nolan

Beilstein J. Nanotechnol. 2021, 12, 704–724, doi:10.3762/bjnano.12.56

• preferred. Predictions made using these descriptors can be used when deciding which metal–substrate combination will be suitable for a particular application where the shape of the metal is vital. Methods All calculations for this study were carried out with density functional theory (DFT) using the Vienna

Nanoporous and nonporous conjugated donor–acceptor polymer semiconductors for photocatalytic hydrogen production

• Zhao-Qi Sheng,
• Yu-Qin Xing,
• Yan Chen,
• Guang Zhang,
• Shi-Yong Liu and
• Long Chen

Beilstein J. Nanotechnol. 2021, 12, 607–623, doi:10.3762/bjnano.12.50

• activity than double F substitution, and the polymer with the methoxy group at the meta site and the F atom at the para site yields the highest HER due to the excellent mobility of photogenerated charge carriers and the broad light absorption range. DFT calculations also verified that incorporating F on

• with pyrene and BT exhibited the best HER (177.50 μmol·h−1, 20 mg) due to low charge recombination and strong photoinduced charge transfer. Furthermore, DFT calculations (Figure 7) indicated that incorporating halogen atoms in both P43 and P44 (Figure 5) reduces the energy barrier for forming H

• hyperbranched Pdots. Araujo et al. [72] studied several BT-containing small molecules with A–D–A architectures through theoretical calculations. They found that small molecules could also mediate photocatalytic water splitting into hydrogen and oxygen. Dibenzothiophene-S,S-dioxide-based conjugated polymers

Stability and activity of platinum nanoparticles in the oxygen electroreduction reaction: is size or uniformity of primary importance?

• Kirill O. Paperzh,
• Anastasia A. Alekseenko,
• Vadim A. Volochaev,
• Ilya V. Pankov,
• Olga A. Safronenko and
• Vladimir E. Guterman

Beilstein J. Nanotechnol. 2021, 12, 593–606, doi:10.3762/bjnano.12.49

• of the NP shape, leading to an increase in the proportion of more active areas, can lead to a significant increase in the Pt/C activity [18]. Moreover, according to the calculations in [17], NPs of each size can have its own optimal shape, which provides the highest ORR mass activity. Nevertheless

Properties of graphene deposited on GaN nanowires: influence of nanowire roughness, self-induced nanogating and defects

• Jakub Kierdaszuk,
• Piotr Kaźmierczak,
• Justyna Grzonka,
• Aleksandra Krajewska,
• Aleksandra Przewłoka,
• Wawrzyniec Kaszub,
• Zbigniew R. Zytkiewicz,
• Marta Sobanska,
• Maria Kamińska,
• Andrzej Wysmołek and
• Aneta Drabińska

Beilstein J. Nanotechnol. 2021, 12, 566–577, doi:10.3762/bjnano.12.47

• graphene deposited on gallium nitride nanowires (GaN NWs) with different variations in height. The electric field induced in GaN predicted by theoretical calculations could reach 5 MV/cm [21]. This is an effect of high spontaneous and piezoelectric polarisations in the wurtzite structure of GaN

• the value of RDD’ ratio equals to 3.5 is characteristic of grain boundaries, five is characteristic of multiple vacancies, seven corresponds to single vacancies, while 13 is observed for sp3 hybridisation defects [20][49]. Furthermore, theoretical calculations predicted values of 1.3 and 10.5 for on

Surface-enhanced Raman scattering of water in aqueous dispersions of silver nanoparticles

• Paulina Filipczak,
• Krzysztof Hałagan,
• Jacek Ulański and
• Marcin Kozanecki

Beilstein J. Nanotechnol. 2021, 12, 497–506, doi:10.3762/bjnano.12.40

• was found that only one water molecule per 10 million is in direct contact with the surface of AgNPs. It is also worthy to mention that the model used to calculate the part of the water molecules in the direct vicinity of AgNPs yielded an overestimated value (the detailed calculations are described in

• calculate the EF. As all measurements were performed under the same conditions, all calculations, for simplicity, were done for 1 dm3 of the samples (water and AgNPs blue dispersion). The enhancement factor for AgNPs blue was calculated by using Equation 1 as follows: ISERS and IRS are integral intensities

• for AgNPs blue and water spectra, respectively (AgNPs blue spectrum after the reabsorption correction) and Nsurf and Nvol are the numbers of water molecules located on the surface of AgNPs and water molecules in pure water in 1 dm3, respectively (for the calculations of these values, see section SI3

Reconstruction of a 2D layer of KBr on Ir(111) and electromechanical alteration by graphene

• Zhao Liu,
• Antoine Hinaut,
• Stefan Peeters,
• Sebastian Scherb,
• Ernst Meyer,
• Maria Clelia Righi and
• Thilo Glatzel

Beilstein J. Nanotechnol. 2021, 12, 432–439, doi:10.3762/bjnano.12.35

• pattern. Comprehensive calculations by DFT, taking into account the observed periodicities, resulted in a new low-energy reconstruction. However, it is fully relaxed into a common cubic structure when a monolayer of graphene is located between substrate and KBr. By using Kelvin probe force microscopy, the

• work functions of the reconstructed and the cubic configuration of KBr were measured and indicate, in accordance with the DFT calculations, a difference of nearly 900 meV. The difference is due to the strong interaction and local charge displacement of the K+/Br− ions and the Ir(111) surface, which are

• temperature and density functional theory (DFT) calculations. The results suggest that this particular reconstruction of KBr occurs on Ir(111), due to a specific correlation of the lattice parameter. When deposited on a single layer of graphene on the same substrate, the topography of the KBr islands returns

Characterization, bio-uptake and toxicity of polymer-coated silver nanoparticles and their interaction with human peripheral blood mononuclear cells

• Sahar Pourhoseini,
• Reilly T. Enos,
• Angela E. Murphy,
• Bo Cai and
• Jamie R. Lead

Beilstein J. Nanotechnol. 2021, 12, 282–294, doi:10.3762/bjnano.12.23

• binding to proteins present in the RPMI. Formation of dissolved silver chloride was suggested by speciation calculations (data not reported, as the accuracy of calculations can be questioned, given the media complexity and difference from those on which the model was validated). There is limited evidence

• sample of Person 5 showed a different trend in the LDH assay than the other samples and it is not clear if this discrepancy was a result of variability between individuals. Excluding the sample of Person 5 from the calculations, the Pearson correlation coefficient indicated a moderate correlation between

Determination of elastic moduli of elastic–plastic microspherical materials using nanoindentation simulation without mechanical polishing

• Hongzhou Li and
• Jialian Chen

Beilstein J. Nanotechnol. 2021, 12, 213–221, doi:10.3762/bjnano.12.17

• elastic modulus extracted according to Equation 8. Oliver and Pharr proposed that β = 1.05 with a potential error of approximately ±0.05, based on their analysis of available results 1.0226 ≤ β ≤ 1.085 from experiments and finite element calculations [6]. Finite Element Method To evaluate the mechanical

TiO_x/Pt₃Ti(111) surface-directed formation of electronically responsive supramolecular assemblies of tungsten oxide clusters

• Marco Moors,
• Yun An,
• Agnieszka Kuc and
• Kirill Yu. Monakhov

Beilstein J. Nanotechnol. 2021, 12, 203–212, doi:10.3762/bjnano.12.16

• supramolecular structures. It is noteworthy that individual W3O9 clusters, according to previous density functional theory (DFT) calculations [11], are characterized by the most stable six-membered ring structure with D3h symmetry. It consists of oxygen-bridged tungsten atoms with two additional terminal oxygen

• with a constant distance between them. The DFT calculations of a very similar oxide phase, grown by a reactive Ti deposition on Pt(111) [25], showed that the brightest spots belong to fourfold oxygen-coordinated titanium atoms, whereas threefold coordinated Ti atoms are depicted with less contrast. The

• atoms remain in the oxidation state +VI and one is reduced to +IV (compare Figure 3c and Figure 3d). The latter one has less unoccupied electronic states and, therefore, is not resolved by scanning with a positive bias voltage. Our DFT calculations of W3O9 and of a hypothetical W3O8 molecule in the gas

Mapping the local dielectric constant of a biological nanostructured system

• Wescley Walison Valeriano,
• Rodrigo Ribeiro Andrade,
• Juan Pablo Vasco,
• Angelo Malachias,
• Bernardo Ruegger Almeida Neves,
• Paulo Sergio Soares Guimarães and
• Wagner Nunes Rodrigues

Beilstein J. Nanotechnol. 2021, 12, 139–150, doi:10.3762/bjnano.12.11

• FIB. Capacitance model with tip, sample, conductive plate, and the parameters used in our calculations. R is the tip apex radius, θ is the tip conical angle, z is the tip–sample distance, h is the sample thickness and εr is the relative permittivity of the sample. The sample is shown on top of the

Numerical analysis of vibration modes of a qPlus sensor with a long tip

• Kebei Chen,
• Zhenghui Liu,
• Yuchen Xie,
• Chunyu Zhang,
• Gengzhao Xu,
• Wentao Song and
• Ke Xu

Beilstein J. Nanotechnol. 2021, 12, 82–92, doi:10.3762/bjnano.12.7

• of the tuning fork prong without a tip. Figure 2b visualizes the mesh distribution used for the calculations. The mesh density increases at the link between the two prongs and near the boundaries of each material. Figure 2c is a zoomed view of the tungsten wire attached to the end of the tuning fork

• case, the volume of the glue in the simulation is approximately equal to the volume of the glue in the experiment. Figure 2d is a false-color representation of the total displacement levels. Warmer colors represent a larger displacement. All calculations were carried out using COMSOL Multiphysics

• used for finite element calculations. Supporting Information Supporting Information File 32: Additional simulation results. Funding The authors gratefully acknowledge the support from the National Key Technologies R&D Program of China (Grant No. 2016YFA0201101), the National Natural Science

Free and partially encapsulated manganese ferrite nanoparticles in multiwall carbon nanotubes

• Saja Al-Khabouri,
• Salim Al-Harthi,
• Toru Maekawa,
• Mohamed E. Elzain,
• Ashraf Al-Hinai,
• Ahmed D. Al-Rawas,
• Abbsher M. Gismelseed,
• Ali A. Yousif and
• Myo Tay Zar Myint

Beilstein J. Nanotechnol. 2020, 11, 1891–1904, doi:10.3762/bjnano.11.170

• , experimentally, bulk MnFe2O4 is known to have semiconductor properties [18]. The spectrum shown in Figure 1e contains a main peak at approx. 5.4 eV and weaker peaks at approx. 9.7 eV and 12.1 eV. By comparing the spectrum with the band structure calculations, the first peak (indicated by an arrow in the spectrum

Kondo effects in small-bandgap carbon nanotube quantum dots

• Patryk Florków,
• Damian Krychowski and
• Stanisław Lipiński

Beilstein J. Nanotechnol. 2020, 11, 1873–1890, doi:10.3762/bjnano.11.169

• changes of the bandgap. In the following we show how, for a given nearly metallic nanotube, one can change the position of high-symmetry points by strain and a magnetic field. Our calculations also show that in a quantum dot formed in a small-bandgap nanotube electron and hole states can degenerate in

• Fermi velocity (vF ≅ 0.8c), D is the nanotube diameter, and a is the distance between carbon atoms in the A lattice and the B lattice of graphene (a ≅ 0.254 nm). Eg is the bandgap energy, where Θ is the chiral angle, . According to tight-binding calculations the value of β corresponding to the

• calculations [27][28]. The SBMFA method best describes systems close to the Kondo fixed point, that is, for the case of deep fully degenerate atomic levels at low temperatures. This approximation correctly describes spin or pseudospin fluctuations and reproduces local Fermi-liquid behavior at zero temperature

Scanning transmission imaging in the helium ion microscope using a microchannel plate with a delay line detector

• Eduardo Serralta,
• Nico Klingner,
• Olivier De Castro,
• Michael Mousley,
• Santhana Eswara,
• Serge Duarte Pinto,
• Tom Wirtz and
• Gregor Hlawacek

Beilstein J. Nanotechnol. 2020, 11, 1854–1864, doi:10.3762/bjnano.11.167

• show the contrast change for low and high scattering angles using BF and ADF detection. We also demonstrate the qualitative match of the contrast in bright-field mode with predictions from binary collision approximation calculations using a test sample. In the case of polycrystalline silicon, we can

Molecular dynamics modeling of the influence forming process parameters on the structure and morphology of a superconducting spin valve

• Alexander Vakhrushev,
• Aleksey Fedotov,
• Vladimir Boian,
• Roman Morari and
• Anatolie Sidorenko

Beilstein J. Nanotechnol. 2020, 11, 1776–1788, doi:10.3762/bjnano.11.160

• calculations, a four-fold decrease in the volume of the nanosystem did not affect the nanocomposite layer composition. The layers are connected at the same places, and the proportion of niobium and cobalt differ slightly from the main part of the sample. The obtained data indicate that the initially selected

• an increase or decrease in the number of deposited atoms per unit time introduced into the system from the evaporation zone. Here, numerical calculations for the nanofilm variations with a 2-fold increase and a 1.5-fold decrease of the deposited atom flux density are performed. The relative layered

• composition of the nanocomposite for the calculations is shown in Figure 10. Here, the fraction of elements in the composition during the nanolayer formation when the deposition rate was reduced by 1.5-fold is shown by the solid lines without markers, the increased intensity is represented by dashed lines

Mapping of integrated PIN diodes with a 3D architecture by scanning microwave impedance microscopy and dynamic spectroscopy

• Rosine Coq Germanicus,
• Peter De Wolf,
• Florent Lallemand,
• Catherine Bunel,
• Serge Bardy,
• Hugues Murray and
• Ulrike Lüders

Beilstein J. Nanotechnol. 2020, 11, 1764–1775, doi:10.3762/bjnano.11.159

• architecture is analysed. sMIM measurements of the different layers of the PIN diode are presented and discussed in terms of detection mechanism, sensitivity, and precision. In the second part, supported by analytic calculations of the equivalent nano-MIS capacitor, a new multidimensional approach, including a

• . These spatio-spectral plots clearly show how the C–V spectrum varies along the depth profile, and also how junctions measured in the sMIM images might change under the applied bias. In the BN region, according to analytic calculations (Figure 8), the n-type region increases when VDC is decreased. We can

• thresholds used. sMIM maps acquired at VDC = 0 V on a large area (83 µm × 54 µm) of the PIN diode device. (a) ∂C/∂V phase, (b) ∂C/∂V amplitude, (c) sMIM-R, and (d) sMIM-C. The distinct locations of the different layers of the device are also indicated. Analytic calculations of the equivalent capacitance

Application of contact-resonance AFM methods to polymer samples

• Sebastian Friedrich and
• Brunero Cappella

Beilstein J. Nanotechnol. 2020, 11, 1714–1727, doi:10.3762/bjnano.11.154

• modulus, but also the measured CR frequency itself are affected by large uncertainties and are often not reproducible. Therefore, several CR-AFM studies on polymers are limited to the mere detection of contrasts in CR frequency, without further calculations and, hence, without a quantitative determination

Selective detection of complex gas mixtures using point contacts: concept, method and tools

• Alexander P. Pospelov,
• Victor I. Belan,
• Dmytro O. Harbuz,
• Volodymyr L. Vakula,
• Lyudmila V. Kamarchuk,
• Yuliya V. Volkova and
• Gennadii V. Kamarchuk

Beilstein J. Nanotechnol. 2020, 11, 1631–1643, doi:10.3762/bjnano.11.146

• reagents produced by the NPL Granum company (Kharkiv, Ukraine). Statistical calculations were made using the WEKA data mining software [57]. Additional control and verification of the results were performed with the SPSS statistical package [58]. The data were processed statistically using the standard

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1615–1622, doi:10.3762/bjnano.11.144

• (111) surface with deposition on thicker CaF2/CaF1/Si(111) films. The identification of mostly single molecules on the CaF1/Si(111) interface layer is explained by the presence of atomic-size defects within this layer. Geometry-optimisation calculations using density functional theory reveal a geometry

• flat-lying geometry is found from geometry-optimisation calculations of a single PTCDA molecule on a CaF2 slab using DFT, whereby an interaction between two carbonyl oxygen atoms and two surface calcium ions leads to a slight deformation of the PTCDA molecule. Methods Sample preparation and STM

• -tracking system [30]. Image data were acquired in constant-current or constant-height mode while applying a sample bias Ub. Gwyddion [31] was used for the image data analysis. Density functional theory calculations were performed using cp2k (http://www.cp2k.org) [32] and parameters similar to previous

Detecting stable adsorbates of (1S)-camphor on Cu(111) with Bayesian optimization

• Jari Järvi,
• Patrick Rinke and
• Milica Todorović

Beilstein J. Nanotechnol. 2020, 11, 1577–1589, doi:10.3762/bjnano.11.140

• monolayer formation and hybrid interfaces. In the following sections, we first introduce our computational methods for adsorbate structure identification with BOSS, the first-principles calculations, and their application on detecting the stable adsorbates of camphor on Cu(111). We then present our results

• corresponding charge distribution of an isolated molecule. With this analysis, we study the effect of adsorption on the electronic structure of camphor in the identified stable structures. First-principles calculations We use density-functional theory to calculate the adsorption energy of camphor on Cu(111) in

• , d23 = 2.081 Å), in agreement with previous calculations [52]. We apply this Cu slab model as a building block in the subsequent study of camphor adsorption. Our other building block is the global minimum conformer of camphor, which we add onto the Cu slab model. The (6 × 4) supercell provides a good

Electrokinetic characterization of synthetic protein nanoparticles

• Daniel F. Quevedo,
• Cody J. Lentz,
• Adriana Coll de Peña,
• Yazmin Hernandez,
• Nahal Habibi,
• Rikako Miki,
• Joerg Lahann and
• Blanca H. Lapizco-Encinas

Beilstein J. Nanotechnol. 2020, 11, 1556–1567, doi:10.3762/bjnano.11.138

• calculations will be shown later. SPNP-BSA-488 and SPNP-BSA-555 were both measured in the EK microdevices and both particle types were found to be trapped at the same potential, that is, 500 V (Figure 2c and Figure 2d). This result suggesting that the presence of the dye does not affect the EK response has

Design of V-shaped cantilevers for enhanced multifrequency AFM measurements

• Mehrnoosh Damircheli and
• Babak Eslami

Beilstein J. Nanotechnol. 2020, 11, 1525–1541, doi:10.3762/bjnano.11.135

• cantilevers in bimodal AFM. Finally, an analytical relationship is developed based on the numerical calculations. Based on this relationship, users can obtain a better understanding of expected phase contrast by providing the dimensions of the cantilever. This relationship can help experimentalists for