Dynamics and fragmentation mechanism of (C₅H₄CH₃)Pt(CH₃)₃ on SiO₂ surfaces

• Kaliappan Muthukumar,
• Harald O. Jeschke and
• Roser Valentí

Beilstein J. Nanotechnol. 2018, 9, 711–720, doi:10.3762/bjnano.9.66

• calculations. Different spin states (i.e., in each case the two lowest possible spin states) were considered, and only the results of the ground state are reported below. The adsorption energy (EA) was defined as EA ≡ ΔE = Etotal − Esubstrate − Eadsorbate, where Etotal, Esubstrate, and Eadsorbate are the

Ab initio study of adsorption and diffusion of lithium on transition metal dichalcogenide monolayers

• Xiaoli Sun and
• Zhiguo Wang

Beilstein J. Nanotechnol. 2017, 8, 2711–2718, doi:10.3762/bjnano.8.270

• monolayers, the adsorption energy, Ead(Li), is calculated using Equation 1: where EMX2+Li and EMX2 are the total energy of the MX2 monolayer with and without Li adsorption, respectively. ELi is the energy of a Li atom in bulk material. The calculated adsorption energy of Li on the stable phase of the MX2

• monolayers is shown in Figure 4. The adsorption energy has positive values for Li adsorbed on 2H-WS2 and 2H-WSe2, which indicates that Li cannot be adsorbed on these two compounds and they are not ideal anodes for LIBs. The other compounds have negative values of adsorption energy. The adsorption energy of

• absolute value of the adsorption energy for Li adsorbed on other compounds is larger than that of 2H-MoS2, so other MX2 compounds are also good anode candidates for LIBs. The adsorption energy as a function of the bandgap of the MX2 monolayer is show in Figure 4. It can also be seen from the figure that

Adsorption of iron tetraphenylporphyrin on (111) surfaces of coinage metals: a density functional theory study

• Hao Tang,
• Nathalie Tarrat,
• Véronique Langlais and
• Yongfeng Wang

Beilstein J. Nanotechnol. 2017, 8, 2484–2491, doi:10.3762/bjnano.8.248

• reference configuration (HS, fcc), the adsorption energy is calculated to be −1.86 eV while the vdW contribution is found to be −1.70 eV. This small energy difference confirms the physisorption of FeTPP on Au(111). The molecule–surface distance of 3.63 ± 0.06 Å is consistent with the presence of the four

• sites of Ag(111) and Cu(111) surfaces (Figure 8). The adsorption energy for HS FeTPP on Ag(111) is −4.99 ± 0.01 eV with a molecule–surface distance of dFeTPP-Ag(111) = 3.06 ± 0.01 Å and an Fe–surface distance of dFe-Ag(111) = 2.82 ± 0.01 Å. On Cu(111), the adsorption energy of HS FeTPP is −4.85 ± 0.02

• , has an adsorption energy of −1.83 ± 0.02 eV with a contribution of vdW interactions of −1.70 eV, and the central porphyrin macrocyle is at a distance of 3.63 ± 0.06 Å above the surface. These physisorption characteristics were confirmed by a small charge transfer (0.24e) from the molecule to the

Modelling focused electron beam induced deposition beyond Langmuir adsorption

• Dédalo Sanz-Hernández and
• Amalio Fernández-Pacheco

Beilstein J. Nanotechnol. 2017, 8, 2151–2161, doi:10.3762/bjnano.8.214

• included. Second, the detailed adsorption state, coverage and order, as well as the electron irradiation, may significantly alter the values for attempt frequency, adsorption energy, and dissociation cross section, as well as the order of desorption [44][45][46][47][48]. These factors are not considered

• isotherms [50], which are variants of type II and III, respectively, with <θ> becoming saturated at high pressures, are not found in these FEBID frequency maps, since we are not considering any ML saturation mechanism here. Saturation due to effects such as a fast decrease of adsorption energy with number

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

• adsorption energy on the Au(111) surface that is 1.6 eV higher than that of C60 molecules. This increased binding energy arises from the saturation by the Au surface of the bonds around the molecular vacancy defect. We therefore interpret the observed features as adsorbed fullerene-derived molecules with C

Modeling adsorption of brominated, chlorinated and mixed bromo/chloro-dibenzo-p-dioxins on C₆₀ fullerene using Nano-QSPR

• Piotr Urbaszek,
• Agnieszka Gajewicz,
• Celina Sikorska,
• Maciej Haranczyk and
• Tomasz Puzyn

Beilstein J. Nanotechnol. 2017, 8, 752–761, doi:10.3762/bjnano.8.78

• the adsorption energy [kcal/mol] for 1,701 PXDDs adsorbed on C60 (PXDD@C60). Based on the QSPR model reported herein, we concluded that the lowest energy PXDD@C60 complexes are those that the World Health Organization (WHO) considers to be less dangerous with respect to the aryl hydrocarbon receptor

• compounds has raised the question: How many halogenated PXDDs congeners will create a PXDD@C60 complex based on weak π–π interactions, and what is the influence of halogen substitution of dioxin congeners in these interactions? The main goal of this study was to calculate the adsorption energy for the

• substituents) in dioxin molecules on the final adsorption energy of the complex by using in silico methods. Our model presented here may provide important information in designing new fullerene applications and assessing the risk of those interactions according to the differences in toxicity caused by the

Calculating free energies of organic molecules on insulating substrates

• Julian Gaberle,
• David Z. Gao and
• Alexander L. Shluger

Beilstein J. Nanotechnol. 2017, 8, 667–674, doi:10.3762/bjnano.8.71

• the thermally accessible energy range. The existence of this second minimum was confirmed using energy-minimisation calculations. The molecule will adsorb with one leg on the step edge with an adsorption energy of 4.7 eV. This illustrates that subtle features in the free-energy profile can be resolved

Graphene functionalised by laser-ablated V₂O₅ for a highly sensitive NH₃ sensor

• Margus Kodu,
• Artjom Berholts,
• Tauno Kahro,
• Mati Kook,
• Peeter Ritslaid,
• Helina Seemen,
• Tea Avarmaa,
• Harry Alles and
• Raivo Jaaniso

Beilstein J. Nanotechnol. 2017, 8, 571–578, doi:10.3762/bjnano.8.61

• charged atoms on the surface. Consequently, the adsorption energy is due to van der Waals forces, and may be less or comparable to kBT (where kB is the Boltzmann constant and T the absolute temperature) for gases at room temperature. The introduction of defects and dopant atoms into graphene can

• drastically increase both the adsorption of pollutant molecules and the influence of gas adsorption on the electronic properties of graphene [6][30]. For instance, adsorption energy (Ea) of an NH3 molecule on regular graphene is relatively small (Ea ≤ 0.11 eV [6][30]), but it is much higher for defect (up to

Fiber optic sensors based on hybrid phenyl-silica xerogel films to detect n-hexane: determination of the isosteric enthalpy of adsorption

• Jesús C. Echeverría,
• Ignacio Calleja,
• Paula Moriones and
• Julián J. Garrido

Beilstein J. Nanotechnol. 2017, 8, 475–484, doi:10.3762/bjnano.8.51

• the porous texture and the interaction or adsorption energy. Molecules cover the external surface, fill the narrow micropores, and condense on meso- and macropores, depending on the relative pressure of the analyte. However, diffusion should also be taken into consideration. The ability of porous

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

• the absolute value of adsorption energy. At the same time, we believe that the general trend in adsorption of heavy metals by graphene surface will not be changed. Another important aspect is the recovery time. According to the transition state theory [61], the recovery time may be written as follows

• : where T is the temperature, kB is Boltzmann’s constant and ν0 is the frequency of the desorption event, and Eads is the adsorption energy. An increase in adsorption energy will cause an increased recovery time. In fact, in the case of strong adsorption, the recovery time will be too long for the sensor

• binding energy of different heavy metals with graphene. Anyway, a trade-off must be reached between the adsorption energy on one side and the recovery time on the other side. The graphene/SiC interface (working in resistor regime) can also function as an effective sensor for the detection of the heavy

A composite structure based on reduced graphene oxide and metal oxide nanomaterials for chemical sensors

• Vardan Galstyan,
• Elisabetta Comini,
• Iskandar Kholmanov,
• Andrea Ponzoni,
• Veronica Sberveglieri,
• Nicola Poli,
• Guido Faglia and
• Giorgio Sberveglieri

Beilstein J. Nanotechnol. 2016, 7, 1421–1427, doi:10.3762/bjnano.7.133

• °C acetone releases more electrons than ethanol due to the interaction between the gas molecules and the adsorbed oxygen on the material surface. It may be one of the reasons of the better response to acetone. Besides, different gases have a different adsorption rate due the variation of adsorption

• energy. Figure 7 reports the calibration curves of the RGO–ZnO and pristine ZnO nanostructures for measuring acetone at a working temperature of 250 °C. The response for both structures shows good linearity with the concentration of acetone. The response of the hybrid structure towards all examined

Three-gradient regular solution model for simple liquids wetting complex surface topologies

• Sabine Akerboom,
• Marleen Kamperman and
• Frans A. M. Leermakers

Beilstein J. Nanotechnol. 2016, 7, 1377–1396, doi:10.3762/bjnano.7.129

Coupled molecular and cantilever dynamics model for frequency-modulated atomic force microscopy

• Michael Klocke and
• Dietrich E. Wolf

Beilstein J. Nanotechnol. 2016, 7, 708–720, doi:10.3762/bjnano.7.63

• [24][27][28]. Lennard-Jones crystals If one uses the Lennard-Jones potential, for simulating dynamic force microscopy, the tip in Figure 1 in general does not remain intact, but may loose its apex atom, if it comes too close to the substrate. This can be shown simply by comparing the adsorption energy

• (the energy, the system gains when an atom is attached to the surface) and the dissociation energy of the apex atom (the energy necessary to detach it from the tip). If the dissociation energy is overcompensated by the adsorption energy, it is more favorable for the apex atom to remain on the substrate

• . To calculate these energies, we place a single atom onto the surface of the substrate and perform an equilibration run by applying the conjugate gradient algorithm. The difference between the total energy of the relaxed system with and without the atom is the adsorption energy. For a substrate with a

First-principles study of the structure of water layers on flat and stepped Pb electrodes

• Xiaohang Lin,
• Ferdinand Evers and
• Axel Groß

Beilstein J. Nanotechnol. 2016, 7, 533–543, doi:10.3762/bjnano.7.47

• adsorption the water–water interaction is modified because of the water–metal interaction, and there is no unambiguous way of disentangling both contributions to the water adsorption energy [29][36]. Results and Discussion As a first step, we consider the adsorption of water on the low-index (111) and (100

• ) surfaces. A single water molecule binds to Pb(111) in the usual fashion [29] through its oxygen atom (see Figure 1a), however, with the relatively small adsorption energy of −0.07 eV at a coverage of 1/3. Reducing the coverage to 1/9 changes the adsorption energy by less than 10 meV. This adsorption energy

• Å. The distances between the oxygen atoms differ to a certain extent. The shortest one is about 3.01 Å, but the average distance is 3.5 Å. In general, the adsorbed water molecules are not hydrogen-bonded to three other water molecules, but just to two. This results in a rather low adsorption energy

Surface-site reactivity in small-molecule adsorption: A theoretical study of thiol binding on multi-coordinated gold clusters

• Elvis C. M. Ting,
• Tatiana Popa and
• Irina Paci

Beilstein J. Nanotechnol. 2016, 7, 53–61, doi:10.3762/bjnano.7.6

• , dispersive interactions held an important place in determining binding methylthiolate/Au binding strengths. As illustrated by the binding data in Table 1, the adsorption energy did not follow a direct, monotonous relationship with the degree of unsaturation of the gold atoms at the binding site. Instead, a

Sub-monolayer film growth of a volatile lanthanide complex on metallic surfaces

• Hironari Isshiki,
• Jinjie Chen,
• Kevin Edelmann and
• Wulf Wulfhekel

Beilstein J. Nanotechnol. 2015, 6, 2412–2416, doi:10.3762/bjnano.6.248

• sites of the herringbone indicates higher adsorption energy at these sites. The molecules can attach here but cannot diffuse further on the surface to form larger islands at room temperature. This preferential nucleation at the elbow sites has been reported for other molecules [17][18]. In the extended

Core-level spectra and molecular deformation in adsorption: V-shaped pentacene on Al(001)

• Anu Baby,
• He Lin,
• Gian Paolo Brivio,
• Luca Floreano and
• Guido Fratesi

Beilstein J. Nanotechnol. 2015, 6, 2242–2251, doi:10.3762/bjnano.6.230

• same system was later investigated with LDA and GGA by Saranya et al. [14] who also obtained a very weak adsorption energy with pentacene adsorbed at larger distances from the Al surface (3.4 Å) in LDA and comparable to the previous ones in GGA. Both papers also report Schottky barriers at the junction

• aligned along the [110] direction [15]. A similar V-shaped deformation was also obtained in the configuration with the long molecular axis along the [010] direction but with 0.42 eV higher adsorption energy. On the contrary, other adsorption configurations would result in planar molecular geometries with

Distribution of Pd clusters on ultrathin, epitaxial TiO_x films on Pt₃Ti(111)

• Christian Breinlich,
• Maria Buchholz,
• Marco Moors,
• Tobias Pertram,
• Conrad Becker and
• Klaus Wandelt

Beilstein J. Nanotechnol. 2015, 6, 2007–2014, doi:10.3762/bjnano.6.204

• further deposition process. Heterogeneous nucleation occurs on a surface of higher corrugation on which the diffusing atoms are trapped at the sites of highest adsorption energy, which thereby become preferred nucleation and growth sites. Obviously, defect sites are such traps. As shown in Figure 5a

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

• manifold degenerated. In our case the units are the C60 molecules and the two different states are “bright” and “dim”. The NN energy is small, but not negligible. According to [26] the adsorption energy of C60 in the 6:6-top position amounts to 0.99 eV and to 1.26 eV in the hex-vac position, but to 1.17 eV

• in the case of a 6:6-top C60 with a hex-vac neighbor (assuming that the adatom resulting from the vacancy formation is located on the surface). This points to a small adsorption energy gain for 6:6-top C60, if they are surrounded by unlike NN, i.e., hex-vac C60. On the other hand, a pure domain

Electron-stimulated purification of platinum nanostructures grown via focused electron beam induced deposition

• Brett B. Lewis,
• Michael G. Stanford,
• Jason D. Fowlkes,
• Kevin Lester,
• Harald Plank and
• Philip D. Rack

Beilstein J. Nanotechnol. 2015, 6, 907–918, doi:10.3762/bjnano.6.94

• facilitated via a catalytic O2-Pt dissociative adsorption process [18][23]; specifically, whereas O2 has a very low adsorption energy (and thus short residence time) on amorphous carbon the Pt surface promotes a dissociative adsorption process with a higher binding energy with consequently higher equilibrium

In situ scanning tunneling microscopy study of Ca-modified rutile TiO₂(110) in bulk water

• Giulia Serrano,
• Beatrice Bonanni,
• Tomasz Kosmala,
• Marco Di Giovannantonio,
• Ulrike Diebold,
• Klaus Wandelt and
• Claudio Goletti

Beilstein J. Nanotechnol. 2015, 6, 438–443, doi:10.3762/bjnano.6.44

• for adsorption [6]. Interestingly, San Miguel et al. [6] report that from increasing the surface coverage of the surface as well as reducing the proximity to an oxygen vacancy, a significant reduction of the adsorption energy for Ca results. This means that calcium dissolution from the TiO2 surface

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

• involves the surface coverage, θ, the adsorption energy, Eads, and the area per surface atom, Aat [15]: Interactions between adsorbates are implicitly taken into account in Equation 1, as these interactions will affect the values of both Eads and θ. An example of Wulff construction is shown in Figure 1 for

Advances in NO₂ sensing with individual single-walled carbon nanotube transistors

• Kiran Chikkadi,
• Matthias Muoth,
• Cosmin Roman,
• Miroslav Haluska and
• Christofer Hierold

Beilstein J. Nanotechnol. 2014, 5, 2179–2191, doi:10.3762/bjnano.5.227

• energy for NO3 on the nanotube. However, it has since been pointed out that the methods used in this paper tend to overestimate the binding energy [41][45] and charge transfer. Dai et al. [41] found that chemisorption of two NO3 molecules, on the other hand, is found to be favorable, with an adsorption

• energy (for two molecules) between −1.4 and 1.9 eV. On the other hand, the results from Ellison et al. [49] by using temperature-programmed desorption (TPD) and Fourier-transform infrared (FTIR) spectroscopy disagree with this suggestion, as they found no evidence for chemisorption. In addition, these

Synthesis, characterization, and growth simulations of Cu–Pt bimetallic nanoclusters

• Subarna Khanal,
• Ana Spitale,
• Nabraj Bhattarai,
• Daniel Bahena,
• J. Jesus Velazquez-Salazar,
• Sergio Mejía-Rosales,
• Marcelo M. Mariscal and
• Miguel José-Yacaman

Beilstein J. Nanotechnol. 2014, 5, 1371–1379, doi:10.3762/bjnano.5.150

• the case of the TO586 Cu seed, the fcc structure is retained and in both cases CuPt alloys are evident, with an enrichment of Pt in the sub-surface layers. In all cases, the Pt deposition begins preferentially at the (100) faces due to the most favorable adsorption energy on open facets. The final

Highly NO₂ sensitive caesium doped graphene oxide conductometric sensors

• Carlo Piloto,
• Marco Notarianni,
• Mahnaz Shafiei,
• Elena Taran,
• Dilini Galpaya,
• Cheng Yan and
• Nunzio Motta

Beilstein J. Nanotechnol. 2014, 5, 1073–1081, doi:10.3762/bjnano.5.120

• and environmental monitoring [12]. Theoretical [13][14] and experimental [15][16][17][18][19] studies have revealed that functionalization of graphene can improve significantly its gas sensing performance [20]. The presence of dopants or defects in the graphene lattice can increase the adsorption

• energy, i.e., the gas molecules can absorb more strongly on the doped or defective graphene than the pristine graphene resulting in an enhancement of the sensitivity or selectivity. Recently, graphene oxide (GO), a graphene layer decorated with oxygen functional groups, has been subject to extensive