Probing the magnetic superexchange couplings between terminal Cu^II ions in heterotrinuclear bis(oxamidato) type complexes

• Mohammad A. Abdulmalic,
• Saddam Weheabby,
• Francois E. Meva,
• Azar Aliabadi,
• Vladislav Kataev,
• Bernd Büchner,
• Frederik Schleife,
• Berthold Kersting and
• Tobias Rüffer

Beilstein J. Nanotechnol. 2017, 8, 789–800, doi:10.3762/bjnano.8.82

• . Experimental Section and Supporting Information File 1, giving thus errors in the determination of the molecular weight of the samples. Further insights into the magnetism of the studied samples can be obtained from the analysis of the temperature dependence of the static magnetic susceptibility χ = M/H. The

• . The temperature dependence of the static magnetization was measured in a temperature range T = 1.8–300 K and at µ0H = 1 T with this device. For these magnetic measurements, single crystals of the individual complexes were taken and gently heated (ca. 35 °C) overnight in vacuum to obtain materials free

• versus magnetic field M(H) of 3 at T = 1.8 K (symbols) together with the fit of M(H) to the Brillouin function with S = 1/2 according to Equation 1 (solid line). Temperature dependence of the magnetic susceptibility χ = M/H and of the corresponding inverse susceptibility χ−1 for 1 (symbols). The black

First examples of organosilica-based ionogels: synthesis and electrochemical behavior

• Andreas Taubert,
• Ruben Löbbicke,
• Barbara Kirchner and
• Fabrice Leroux

Beilstein J. Nanotechnol. 2017, 8, 736–751, doi:10.3762/bjnano.8.77

• finds an Arrhenius-type temperature dependence associated to high ion conductivity. Indeed an optimized composition, MBA40IL, exhibits an ionic conductivity of almost 10−2 S·cm−1 at 357 K (84 °C, the upper limit in this study). Figure 12 however shows that 84 °C is not the upper limit for this system

Diffusion and surface alloying of gradient nanostructured metals

• Zhenbo Wang and
• Ke Lu

Beilstein J. Nanotechnol. 2017, 8, 547–560, doi:10.3762/bjnano.8.59

• kinetics in the preformed GNS layers. Temperature dependence of the diffusion coefficients of Cr in the GNS Fe produced by SMAT and in the CG Fe, in comparison with those for the α-Fe lattice diffusion, the α-Fe GB diffusion and the diffusion in Fe–Cr alloy. Figure reproduced with permission from [31

Impact of contact resistance on the electrical properties of MoS₂ transistors at practical operating temperatures

• Filippo Giannazzo,
• Gabriele Fisichella,
• Aurora Piazza,
• Salvatore Di Franco,
• Giuseppe Greco,
• Simonpietro Agnello and
• Fabrizio Roccaforte

Beilstein J. Nanotechnol. 2017, 8, 254–263, doi:10.3762/bjnano.8.28

• main limiting factors for suitable device performance. Furthermore, to gain a deeper understanding of MoS2 FETs under practical operating conditions, it is necessary to investigate the temperature dependence of the main electrical parameters, such as the field effect mobility (μ) and the threshold

• determined and it was found to increase with T as RC proportional to T3.1. The contribution of RC to the extraction of μ and Vth was evaluated, showing a more than 10% underestimation of μ when the effect of RC is neglected, whereas the effect on Vth is less significant. The temperature dependence of μ and

• 373 K, which was explained in terms of electron trapping at MoS2/SiO2 interface states. Keywords: contact resistance; mobility; MoS2; temperature dependence; threshold voltage; Introduction Transition metal dichalcogenides (TMDs) are compound materials formed by the Van der Waals stacking of MX2

Electron energy relaxation under terahertz excitation in (Cd_1−xZn_x)₃As₂ Dirac semimetals

• Alexandra V. Galeeva,
• Ivan V. Krylov,
• Konstantin A. Drozdov,
• Anatoly F. Knjazev,
• Alexey V. Kochura,
• Alexander P. Kuzmenko,
• Vasily S. Zakhvalinskii,
• Sergey N. Danilov,
• Ludmila I. Ryabova and
• Dmitry R. Khokhlov

Beilstein J. Nanotechnol. 2017, 8, 167–171, doi:10.3762/bjnano.8.17

• range 4.2–300 K. The resistivity temperature dependence is typical for degenerate semiconductors: the resistivity decrease with decreasing temperature from 300 K to 20 K is followed by a further saturation at T < 20 K. Since the free electron concentration does not change, this resistivity variation is

• completely determined by the mobility temperature dependence. It is important to note that the free electron concentration in the samples studied differs by a factor of four. The low temperature mobility absolute values are very high and exceed 105 cm2/(V·s). The main tool of the study was the measurement of

Nanocrystalline TiO₂/SnO₂ heterostructures for gas sensing

• Barbara Lyson-Sypien,
• Anna Kusior,
• Mieczylaw Rekas,
• Jan Zukrowski,
• Marta Gajewska,
• Katarzyna Michalow-Mauke,
• Thomas Graule,
• Marta Radecka and
• Katarzyna Zakrzewska

Beilstein J. Nanotechnol. 2017, 8, 108–122, doi:10.3762/bjnano.8.12

• , the temperature dependence of R0/R follows R0 vs temperature, because R is almost constant. On the other hand, in the case of the TiO2-rich sample both R0 and R exhibit a similar temperature dependence, which leads to a gas response R0/R almost independent of the temperature. In order to study the

• ). The gas-sensor response S is defined in Equation 4. Dynamic changes in the electrical resistance, R, of: a) 90 mol % SnO2/10 mol % TiO2; b) 10 mol % SnO2/90 mol % TiO2 heterostructures upon interaction with 1100 ppm H2. τ denotes the recovery time. Temperature dependence of the electrical resistance

Sub-nanosecond light-pulse generation with waveguide-coupled carbon nanotube transducers

• Felix Pyatkov,
• Svetlana Khasminskaya,
• Vadim Kovalyuk,
• Frank Hennrich,
• Manfred M. Kappes,
• Gregory N. Goltsman,
• Wolfram H. P. Pernice and
• Ralph Krupke

Beilstein J. Nanotechnol. 2017, 8, 38–44, doi:10.3762/bjnano.8.5

• ,mod(T) presented in Figure 2b (red symbols). Since the limited detection range of the CCD camera allows for the detection of broadband CNT-emitted light only for hc/λ >> kT, the temperature dependence of Iintegrated,mod(T) can be described using Wien’s approximation of Planck’s law. The best fit to

Obtaining and doping of InAs-QD/GaAs(001) nanostructures by ion beam sputtering

• Sergei N. Chebotarev,
• Alexander S. Pashchenko,
• Leonid S. Lunin,
• Elena N. Zhivotova,
• Georgy A. Erimeev and
• Marina L. Lunina

Beilstein J. Nanotechnol. 2017, 8, 12–20, doi:10.3762/bjnano.8.2

• signal was registered by the monochromator MDR-23 and the cooled germanium p-i-n photo diode. Results and Discussion Temperature The temperature dependence of ion beam sputtering was studied under the following conditions. A constant ion beam current of 120 µA was chosen, and the energy of the ions was

Solvent-mediated conductance increase of dodecanethiol-stabilized gold nanoparticle monolayers

• Patrick A. Reissner,
• Jean-Nicolas Tisserant,
• Antoni Sánchez-Ferrer,
• Raffaele Mezzenga and
• Andreas Stemmer

Beilstein J. Nanotechnol. 2016, 7, 2057–2064, doi:10.3762/bjnano.7.196

• EtOH and THF rather points towards interdigitation than a collapse of alkyl tails. Badia et al. already suggested interdigitation of alkanes surrounding gold nanoparticles and found a temperature dependence on the alkyl chain ordering by transmission electron microscopy [21]. On flat surfaces alkane

Nanostructured SnO₂–ZnO composite gas sensors for selective detection of carbon monoxide

• Paul Chesler,
• Cristian Hornoiu,
• Susana Mihaiu,
• Cristina Vladut,
• Jose Maria Calderon Moreno,
• Mihai Anastasescu,
• Carmen Moldovan,
• Bogdan Firtat,
• Costin Brasoveanu,
• George Muscalu,
• Ion Stan and
• Mariuca Gartner

Beilstein J. Nanotechnol. 2016, 7, 2045–2056, doi:10.3762/bjnano.7.195

• observed. A value of RS = 7 is obtained for 600 ppm of CO, at a working temperature of 210 °C. This value is higher than the response of the individual components and also higher than all of the other composites. A temperature dependence study is shown in Figure 11 for the S2 sensor. From Figure 11 it can

Ferromagnetic behaviour of ZnO: the role of grain boundaries

• Boris B. Straumal,
• Svetlana G. Protasova,
• Andrei A. Mazilkin,
• Eberhard Goering,
• Gisela Schütz,
• Petr B. Straumal and
• Brigitte Baretzky

Beilstein J. Nanotechnol. 2016, 7, 1936–1947, doi:10.3762/bjnano.7.185

• coercive force Hc of about 0.01–0.02 T (see insets in Figure 4). All three samples have grain sizes well below the barrier value (Figure 2) leading to the FM behaviour. Js increases linearly with the increasing thickness of the ZnO film (Figure 4). The temperature dependence of Js permits to estimate the

Properties of Ni and Ni–Fe nanowires electrochemically deposited into a porous alumina template

• Alla I. Vorobjova,
• Dmitry L. Shimanovich,
• Kazimir I. Yanushkevich,
• Sergej L. Prischepa and
• Elena A. Outkina

Beilstein J. Nanotechnol. 2016, 7, 1709–1717, doi:10.3762/bjnano.7.163

• heights is presented. The structural properties of PA/Ni and PA/Ni–Fe NWs, as well as the temperature dependence of the specific magnetization of these nanocomposites are investigated and discussed. Experimental Preparation of porous alumina template The preparation technique and the thickness of the PA

• the alumina template are presented in Table 4. Further, the investigations of magnetic properties of the obtained composite materials, such as Curie temperature (TC) and specific magnetization as a function of temperature σ(T) have been performed and analyzed. The temperature dependence of σ(T) was

• that of the Ni sample or bulk Ni, but lower than that of bulk Fe and Py. The possible reasons for the different structural and magnetic properties of single- (Ni) and two-component (Ni–Fe) NWs formed under identical conditions have been discussed. While studying the temperature dependence of the

Nonlinear thermoelectric effects in high-field superconductor-ferromagnet tunnel junctions

• Stefan Kolenda,
• Peter Machon,
• Detlef Beckmann and
• Wolfgang Belzig

Beilstein J. Nanotechnol. 2016, 7, 1579–1585, doi:10.3762/bjnano.7.152

• are always unequal. In this case the generalized nonlinear coefficient η also contains the temperature dependence of the regular voltage-driven tunnel current, and there is no simple relation to the symmetry of the spectral conductance. Nonlinear thermoelectric coefficients and their symmetries have

• , this becomes mainly relevant close to Tc and we will in the following neglect the temperature dependence. The following derivation will be based on the identity valid for arbitrary bias voltage. Hence we can write and finally This is the main theoretical result and can directly be applied to the

Influence of synthesis conditions on microstructure and phase transformations of annealed Sr₂FeMoO_6−x nanopowders formed by the citrate–gel method

• Marta Yarmolich,
• Nikolai Kalanda,
• Sergey Demyanov,
• Herman Terryn,
• Jon Ustarroz,
• Maksim Silibin and
• Gennadii Gorokh

Beilstein J. Nanotechnol. 2016, 7, 1202–1207, doi:10.3762/bjnano.7.111

• temperature dependence of the heat capacity derivative of nanopowders, SFMO-4, SFMO-6 and SFMO-9. Crystal lattice parameters and degree of superstructural ordering of Fe/Mo cations of SFMO-4, SFMO-6, and SFMO-9 powder samples annealed for 4 h at 1120, 1170, and 1220 K. Acknowledgements The reported study was

Fast diffusion of silver in TiO₂ nanotube arrays

• Wanggang Zhang,
• Yiming Liu,
• Diaoyu Zhou,
• Hui Wang,
• Wei Liang and
• Fuqian Yang

Beilstein J. Nanotechnol. 2016, 7, 1129–1140, doi:10.3762/bjnano.7.105

• Equation 7. Using the linear regression to fit the experimental data in Figure 8, one obtains the diffusivity of 6.87 × 10−18 m2/s. It is known that the temperature dependence of diffusivity follows an Arrhenius relation as D = D0·exp(−Q/RT) with D0 being a pre-exponential constant, Q is the activation

• energy for the rate process, R is the gas constant, and T is the absolute temperature. Using the Arrhenius relation, the temperature dependence of the migration distance of Ag on the outmost surface of the TiO2 nanotubes during the heat treatment can be expressed as As shown in Figure 5d, Ag migrated

• heat treatment at 500 °C for 2 h. Figure 9 shows the temperature dependence of the migration distance of Ag atoms on the outmost surface of the TiO2 nanotubes for a heat treatment of 2 h. Using Equation 8 to fit the experimental data shown in Figure 9, one obtains the activation energy of 157 kJ/mol

Phenalenyl-based mononuclear dysprosium complexes

• Yanhua Lan,
• Andrea Magri,
• Olaf Fuhr and
• Mario Ruben

Beilstein J. Nanotechnol. 2016, 7, 995–1009, doi:10.3762/bjnano.7.92

• ’ has been obtained only in a small quantity. Therefore, the magnetic studies on this compound were not feasible yet. Static magnetic properties The temperature dependence of the dc magnetic susceptibility has been measured in an applied magnetic field of 1000 Oe in the temperature range between 1.8 and

• field of 500 Oe is applied to investigate the frequency and temperature dependence of the ac susceptibility leading to a relaxation time Δ of the relaxation pathway in the temperature range between 7 and 10 K of 36.5 K and its pre-exponential factor τ0 of 2.0 × 10−6 s. Below 7 K, the relaxation time

• entire temperature range of 1.8–13 K. From 7.0 to 13 K, the small α values below 0.16 are compatible with the SMM behavior. The process within this observed temperature range is thermally activated and leads to the exponential temperature dependence of the relaxation time of 3.3 × 10−6 s, which is a

Thickness dependence of the triplet spin-valve effect in superconductor–ferromagnet–ferromagnet heterostructures

• Daniel Lenk,
• Vladimir I. Zdravkov,
• Jan-Michael Kehrle,
• Günter Obermeier,
• Aladin Ullrich,
• Roman Morari,
• Hans-Albrecht Krug von Nidda,
• Claus Müller,
• Mikhail Yu. Kupriyanov,
• Anatolie S. Sidorenko,
• Siegfried Horn,
• Rafael G. Deminov,
• Lenar R. Tagirov and
• Reinhard Tidecks

Beilstein J. Nanotechnol. 2016, 7, 957–969, doi:10.3762/bjnano.7.88

• reduction is varying in magnitude. To separate the triplet SSV effect from the reduction of Tc by the applied magnetic field, we approximate the temperature dependence of the parallel critical field by a Ginzburg–Landau (GL)-like behavior. According to [74], a superconducting thin film shows a temperature

• the free standing Nb film is assumed to be TcS = 6.1 K, yielding hF1 = 8.8 and hF2 = 606. If we take into account an enhancement factor of the slope of the temperature dependence of the upper critical field in [9], we obtain the coherence length in the superconductor ξS = 7.3 nm. According to Butler

• dependence of the upper critical field (parallel to the film plane) given by Hc(T) = Hc(0)(1 − T/Tc0)α. Here, Tc0 is the critical temperature, i.e., the superconducting transition temperature in the absence of currents and magnetic fields, and α is a parameter given by the effective dimensionality of the

Thermo-voltage measurements of atomic contacts at low temperature

• Ayelet Ofarim,
• Bastian Kopp,
• Thomas Möller,
• León Martin,
• Johannes Boneberg,
• Paul Leiderer and
• Elke Scheer

Beilstein J. Nanotechnol. 2016, 7, 767–775, doi:10.3762/bjnano.7.68

• where the highest ΔT was tens of kelvins. In addition, the possibility to scan the laser beam across the sample was favorable for disentangling thermo-voltage effects from artifacts due to the temperature dependence of the lead resistances and to maximize the effective ΔT. The possibility to use the

• temperature dependence of the lead resistance for the determination of ΔT was also applied in [20]. A temperature gradient achieved by a laser source has been used before for contacts realized by pores through a freestanding membrane, but the ΔT achieved was only about 50 mK for a relatively wide tunnel

• temperature dependence of the resistivity should be dominated by electron-phonon scattering, we obtained an effective thickness of 63 nm. This reduction can be caused by the formation of a dead layer or by increased roughness due to the etching process. The complete length of the sensor leads including the

Determination of the compositions of the DIGM zone in nanocrystalline Ag/Au and Ag/Pd thin films by secondary neutral mass spectrometry

• Gábor Y. Molnár,
• Shenouda S. Shenouda,
• Gábor L. Katona,
• Gábor A. Langer and
• Dezső L. Beke

Beilstein J. Nanotechnol. 2016, 7, 474–483, doi:10.3762/bjnano.7.41

• similar considerations as in Equation 1, that the composition of B left behind the moving boundary in A (faster side) can be given as: Thus from the investigations of the temperature dependence of the saturation values one can get estimations on the DA/DB ratios on both sides of the diffusion couple. In

• , predicting a higher value in the slower component (in B). Indeed in our recent paper on Ag/Au nanocrystalline thin films at 150 °C [16] it was obtained that the saturation level of Au in Ag was lower than that of Ag in Au. In this communication we report experimental results on the temperature dependence of

• temperatures, respectively), the temperature dependence of this ratio has also the correct sign. Figure 8 illustrates that it increases with decreasing temperature, according to an Arrhenius function. The common slope of the two lines, gives the following value for the difference of the activation energies; ∆Q

Plasticity-mediated collapse and recrystallization in hollow copper nanowires: a molecular dynamics simulation

• Amlan Dutta,
• Arup Kumar Raychaudhuri and
• Tanusri Saha-Dasgupta

Beilstein J. Nanotechnol. 2016, 7, 228–235, doi:10.3762/bjnano.7.21

• in the first 6–7 ps of the simulation. Following this rise, the potential energy decreases with time, finally reaching saturation. The trends in the temperature dependence of this saturated value are found to be opposite in temperature regimes above and below Tcross. In the low-temperature regime (T

• corresponds to the extent of collapse of the inner bore, which is found to be complete in the high-temperature regime and incomplete in the low-temperature regime. The temperature-dependence of the time of collapse in the high-temperature regime is found to follow the Arrhenius relation (see inset). (a

Charge injection and transport properties of an organic light-emitting diode

• Peter Juhasz,
• Juraj Nevrela,
• Michal Micjan,
• Miroslav Novota,
• Jan Uhrik,
• Lubica Stuchlikova,
• Jan Jakabovic,
• Ladislav Harmatha and
• Martin Weis

Beilstein J. Nanotechnol. 2016, 7, 47–52, doi:10.3762/bjnano.7.5

• steady-state current density–voltage characteristics [5][6], or measurement in time- or frequency-domain, such as transient currents [7] and impedance spectroscopy [8][9]. Furthermore, the measurements can be extended by the temperature dependence of electrical properties which reveal the thermally

Blue and white light emission from zinc oxide nanoforests

• Nafisa Noor,
• Luca Lucera,
• Thomas Capuano,
• Venkata Manthina,
• Alexander G. Agrios,
• Helena Silva and
• Ali Gokirmak

Beilstein J. Nanotechnol. 2015, 6, 2463–2469, doi:10.3762/bjnano.6.255

• heating, the current paths will change depending on the temperature dependence of the resistivity of these two materials. Due to the large difference in resistivity, however, it is likely that the current flows mostly through the polysilicon substrate until the electrical breakdown of air or the ZnO

Nanoscale rippling on polymer surfaces induced by AFM manipulation

• Mario D’Acunto,
• Franco Dinelli and
• Pasqualantonio Pingue

Beilstein J. Nanotechnol. 2015, 6, 2278–2289, doi:10.3762/bjnano.6.234

• ’ after the spin coating deposition step. In this way, part of the solvent remains trapped in the polymeric thin film and the specific patterning procedure employed leads to the production of well-ordered ripple structures. Temperature dependence: The temperature (T) dependence of nanorippling can be

Simulation of thermal stress and buckling instability in Si/Ge and Ge/Si core/shell nanowires

• Suvankar Das,
• Amitava Moitra,
• Mishreyee Bhattacharya and
• Amlan Dutta

Beilstein J. Nanotechnol. 2015, 6, 1970–1977, doi:10.3762/bjnano.6.201

• the CTE as constant over the entire range of operating temperatures. This may be a reasonable assumption when ΔTc remains within a few tens of Kelvin. However, if the temperature varies over a much wider range, or the CTE is highly sensitive to temperature, the temperature dependence, α(T), can be

Continuum models of focused electron beam induced processing

• Milos Toth,
• Charlene Lobo,
• Vinzenz Friedli,
• Aleksandra Szkudlarek and
• Ivo Utke

Beilstein J. Nanotechnol. 2015, 6, 1518–1540, doi:10.3762/bjnano.6.157

• physisorbed species take ca. 10−6 s to populate the surface and reach a steady state, whereas it takes the chemisorbed species ca. 1 s to reach a steady state. Equation 47 can be used to calculate the temperature-dependence of FEBID, as shown in Figure 14 for the case of TEOS [5]. The contribution to growth

• temperature dependence seen in Figure 14 (i.e., a decrease in the physisorption component followed by a peak caused by chemisorption) exists only if kconv << kp << kc [5]. A practical benefit of performing FEBID at elevated temperatures (whereby, in this case, T ≥ 350 K) is that the deposits have much higher