Two-dimensional molecular networks at the solid/liquid interface and the role of alkyl chains in their building blocks

• Suyi Liu,
• Yasuo Norikane and
• Yoshihiro Kikkawa

Beilstein J. Nanotechnol. 2023, 14, 872–892, doi:10.3762/bjnano.14.72

• and in real time [38][39][40][41][42]. In the 2D assemblies at the solid/liquid interface, non-covalent interactions play an essential role in the molecular orientation and arrangement. Among the intermolecular interactions, directional and relatively strong interactions, such as hydrogen bonding

Revealing local structural properties of an atomically thin MoSe₂ surface using optical microscopy

• Lin Pan,
• Peng Miao,
• Anke Horneber,
• Alfred J. Meixner,
• Pierre-Michel Adam and
• Dai Zhang

Beilstein J. Nanotechnol. 2022, 13, 572–581, doi:10.3762/bjnano.13.49

• , which is parallel to the sample plane. To explain this phenomenon, we turn our discussions to the molecular orientation of CuPc on the MoSe2 flake. For a thin film thermally evaporated on a MoS2 flake surface, the CuPc molecule has been reported to adopt π-face-on orientation because the Cu metal center

• of face-on lying CuPc and the MoSe2 flake is the most efficient. With increasing film thickness, we assume that the CuPc molecular orientation varies, such as adopting a tilt angle with respect to the sample surface. The evolution of molecular orientation was observed in a FePc thin film that was

• possible when using the pure |Ex,y|2 component of a focused azimuthally polarized beam. To summarize, our results show that the CuPc molecules likely adopt a face-on orientation on the MoSe2 flake, similar to the case of MoS2 flakes. This molecular orientation facilitates the first-layer effect, which

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

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

• rationalised by nucleation at defects present within the CaF1 interface layer. In contrast, the CaF2/CaF1 layer is mostly defect-free. A statistical analysis revealed a preferred molecular orientation of the long molecular axis along a CaF2 direction, in full agreement with the DFT-calculated optimum

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

• , we study the adsorption of camphor on Cu(111) with respect to molecular orientation and location. We define the PES of adsorption in a 6D phase space with three rotational angles (α, β, γ) and three translational directions (x, y, z), which correspond to the Cu lattice directions [10−1], [−12−1] and

• (3D), we obtained a qualitative description of the adsorption properties of camphor on Cu(111). We gained insight into the estimated adsorption height of the molecule and acquired the ranges of adsorption energy with respect to molecular orientation and the adsorption site. The rotational energy

• identified structures, we observed minor changes in the molecular orientation, the adsorption site, and the adsorption energy. This effectively confirms the accuracy of the surrogate model of the 6D PES. Negligible changes in the internal structure of camphor and the Cu slab in the relaxation validates the

Adsorption and self-assembly of porphyrins on ultrathin CoO films on Ir(100)

• Feifei Xiang,
• Tobias Schmitt,
• Marco Raschmann and
• M. Alexander Schneider

Beilstein J. Nanotechnol. 2020, 11, 1516–1524, doi:10.3762/bjnano.11.134

• and the closest H atom of the macrocycle. Expecting some distortions of the molecule on the surface, this is well in the range of dipolar and hydrogen bond distances [25][30][45]. From the molecular orientation of the assembly marked by the black rectangle in Figure 6a, shown in detail in Figure 6c

• view, respectively, of the relaxed structure of 1 on 1BL CoO according to our DFT calculations. (c) Calculated total energy difference of 1 as a function of the molecular orientation on CoO ultrathin films. Significant rotational barriers of 0.9 eV exist on the 1BL film, while on the 2BL film the

• used. The lateral size was eight c(10 × 2) unit cells for the 1BL system (27.1 × 21.7 Å2) and eight c(8 × 2) unit cells as approximation for the 2BL system ((21.7 Å)2). These cell sizes ensured that the distance between repeated images of the molecules was always larger than 4.1 Å in any molecular

Controlling the electronic and physical coupling on dielectric thin films

• Philipp Hurdax,
• Michael Hollerer,
• Larissa Egger,
• Georg Koller,
• Xiaosheng Yang,
• Anja Haags,
• Serguei Soubatch,
• Frank Stefan Tautz,
• Mathias Richter,
• Alexander Gottwald,
• Peter Puschnig,
• Martin Sterrer and
• Michael G. Ramsey

Beilstein J. Nanotechnol. 2020, 11, 1492–1503, doi:10.3762/bjnano.11.132

• photoelectron spectroscopy [20]. Similarly, the LEED technique will probably not be sensitive to the charge state per se, although differences in the molecular orientation and in the long-range order might occur. With a thorough analysis and molecular orbital resolution, it should be possible to distinguish

Protruding hydrogen atoms as markers for the molecular orientation of a metallocene

• Linda Laflör,
• Michael Reichling and
• Philipp Rahe

Beilstein J. Nanotechnol. 2020, 11, 1432–1438, doi:10.3762/bjnano.11.127

• cyclopentadienyl (Cp) rings. Simulated NC-AFM images show an excellent agreement with experimental constant-height NC-AFM data of FDCA molecules at several tip–sample distances. By measuring this distinct dumbbell shape together with the molecular orientation, a strategy is proposed to determine the conformation

• molecular orientation on the surface. The experimental observation of the dumbbell shape suggests that the prerequisite of a stable tip during repulsive interactions with the hydrogen atoms can easily be fulfilled, even at room temperature. This is in line with previous findings of stable tips for sub

• at decreasing tip–sample distances for a row of FDCA molecules, each in geo 2. The red arrows mark the direction and the dashed blue line (forming an angle of 60° with the direction) the molecular orientation for geo 2. (d) Top view and (e) side view of the simulation cell using geo 2 from [22

Impact of fluorination on interface energetics and growth of pentacene on Ag(111)

• Qi Wang,
• Meng-Ting Chen,
• Antoni Franco-Cañellas,
• Bin Shen,
• Thomas Geiger,
• Holger F. Bettinger,
• Frank Schreiber,
• Ingo Salzmann,
• Alexander Gerlach and
• Steffen Duhm

Beilstein J. Nanotechnol. 2020, 11, 1361–1370, doi:10.3762/bjnano.11.120

• the observed identical HOMO level position in all three monolayers. For an in-depth discussion of the multilayer electronic structure, for which the valence electron spectra were strikingly different (Figure 3a), knowledge about the morphology and the molecular orientation was indispensable [91][92

Templating effect of single-layer graphene supported by an insulating substrate on the molecular orientation of lead phthalocyanine

• K. Priya Madhuri,
• Abhay A. Sagade,
• Pralay K. Santra and
• Neena S. John

Beilstein J. Nanotechnol. 2020, 11, 814–820, doi:10.3762/bjnano.11.66

• specific device applications. Keywords: conducting atomic force microscopy (C-AFM); lead phthalocyanine (PbPc); molecular orientation; single-layer graphene; substrate effect; two-dimensional grazing incidence X-ray diffraction (2D-GIXRD); Introduction Organic semiconductors have been extensively used in

• ) substrate [24]. It will be interesting to explore the molecular orientation of nonplanar PbPc on single-layer graphene supported on a substrate. In this study, we have investigated the molecular orientation of a PbPc film deposited on chemical vapor deposition (CVD)-grown graphene transferred onto a SiO2/Si

• found to be 2.82 nm. Wang et al. carried out a similar study by depositing a 10 nm thin ZnPc film on a graphene/SiO2/Si substrate to study the effects of the molecular orientation on the interfacial electronic properties. The roughness of the film was reported to be 2.47 ± 0.28 nm [19]. The crystallite

Mobility of charge carriers in self-assembled monolayers

• Zhihua Fu,
• Tatjana Ladnorg,
• Hartmut Gliemann,
• Alexander Welle,
• Asif Bashir,
• Michael Rohwerder,
• Qiang Zhang,
• Björn Schüpbach,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2019, 10, 2449–2458, doi:10.3762/bjnano.10.235

• °) to determine the molecular orientation. Infrared reflection-absorption spectroscopy (IRRAS) was performed on a Bruker VERTEX80 spectrometer (Bruker Optics GmbH) by investigating the PAT-SAM on Au/silicon wafers. As a background sample we used a SAM of deuterated octadecanethiol on an Au/silicon wafer

• would not go in line with the almost upright molecular orientation determined from NEXAFS. We thus conclude that each of the protrusions is caused by two molecules, reducing the area per molecule to 0.287 nm2, which is the same value as found for anthracene-2-thiolate monolayers (0.287 nm2) [35]. The

A silver-nanoparticle/cellulose-nanofiber composite as a highly effective substrate for surface-enhanced Raman spectroscopy

• Yongxin Lu,
• Yan Luo,
• Zehao Lin and
• Jianguo Huang

Beilstein J. Nanotechnol. 2019, 10, 1270–1279, doi:10.3762/bjnano.10.126

• weaker and red-shifted to 1305 cm−1. Moreover, two new bands at 1382 and 1422 cm−1 attributed to the ring breathing vibrations of the thymine moiety of thymidine raised. These spectral features, which depend on the specific molecular orientation of the analyte on the silver surface, indicate the

Nanoscale optical and structural characterisation of silk

• Meguya Ryu,
• Reo Honda,
• Adrian Cernescu,
• Arturas Vailionis,
• Armandas Balčytis,
• Jitraporn Vongsvivut,
• Jing-Liang Li,
• Denver P. Linklater,
• Elena P. Ivanova,
• Vygantas Mizeikis,
• Mark J. Tobin,
• Junko Morikawa and
• Saulius Juodkazis

Beilstein J. Nanotechnol. 2019, 10, 922–929, doi:10.3762/bjnano.10.93

• crystalline building blocks of silk. Nanoscale optical and structural properties of silk have been measured from 100 nm thick longitudinal slices of silk fibers with ca. 10 nm resolution, the highest so far. Optical sub-wavelength resolution in hyperspectral mapping of absorbance and molecular orientation

• properties of a material are interrelated. By using a wide spectrum of electromagnetic waves from visible light to terahertz radiation, it is possible to gain insights into complex hierarchical structures of composite materials. For materials with strong structural anisotropy, defined by the molecular

• orientation and alignment of crystalline microvolumes, it is important to characterise structure at the highest lateral and longitudinal resolutions [6][7]. Anderson localisation of light and thermal cooling of silk at IR wavelengths was recently demonstrated to be related to the fibril substructure of silk

Heterostuctures of 4-(chloromethyl)phenyltrichlorosilane and 5,10,15,20-tetra(4-pyridyl)-21H,23H-porphine prepared on Si(111) using particle lithography: Nanoscale characterization of the main steps of nanopatterning

• Phillip C. Chambers and
• Jayne C. Garno

Beilstein J. Nanotechnol. 2018, 9, 1211–1219, doi:10.3762/bjnano.9.112

• differences in structure and conformation [15]. The submolecular structure of cobalt and copper phthalocyanines on gold substrates were resolved with STM by Lu et al. [16]. The differences in central metals were resolved for a mixed sample. The molecular orientation and molecular switching properties of a

Dynamic behavior of nematic liquid crystal mixtures with quantum dots in electric fields

• Emil Petrescu,
• Cristina Cirtoaje and
• Octavian Danila

Beilstein J. Nanotechnol. 2018, 9, 399–406, doi:10.3762/bjnano.9.39

• depend on the molecular orientation so we may neglect it because it disappears when applying the Euler–Lagrange equation. Thus, we may write: where and is the effective dielectric anisotropy of the liquid crystal containing quantum dots as a function of the dielectric anisotropy of the LC, (εa), of the

• . Nematic molecular orientation around an ellipsoidal QD. Experimental setup for the dynamic study of the LC + QDs mixture. Fréedericksz transition for 5CB and 5CB + QD. Lines are guide to the eyes. Dynamic measurement of emergent light intensity: a) for LC sample when the field is on; b)for LC sample when

• the field is off; c) for LC + QDs sample when the field is on; for LC + QDs sample when the field is off. The dots represent experimental values and the red lines are theoretical representations. Schematic representation of the molecular orientation around a QD a) when the field is switched on b) when

Dynamic behavior of a nematic liquid crystal with added carbon nanotubes in an electric field

• Emil Petrescu and
• Cristina Cirtoaje

Beilstein J. Nanotechnol. 2018, 9, 233–241, doi:10.3762/bjnano.9.25

• ., parallel to the z-axis), the molecular orientation is characterized by the distortion angle θ between the director and the x-axis (Figure 1). Thus, the free energy of the liquid crystal is: where θz = ∂θ/∂z, d is the cell thickness and K1, K3 are elastic constants. The interaction free energy of a liquid

• compounds can be made and a deeper understanding of the anchoring forces influence on the physical properties of the mixture is provided. Liquid crystal molecular orientation inside a LC cell exposed to an electric field. is the undisturbed molecular director and is the molecular director when the

Towards molecular spintronics

• Georgeta Salvan and
• Dietrich R. T. Zahn

Beilstein J. Nanotechnol. 2017, 8, 2464–2466, doi:10.3762/bjnano.8.245

• . Fabrication, characterization, and optimization of molecular thin films and interfaces: Various deposition techniques to create suitable molecular films were tested for a variety of molecules. The structure, morphology, and molecular orientation of the layers were fundamentally characterized and optimized

Non-intuitive clustering of 9,10-phenanthrenequinone on Au(111)

• Ryan D. Brown,
• Rebecca C. Quardokus,
• Natalie A. Wasio,
• Jacob P. Petersen,
• Angela M. Silski,
• Steven A. Corcelli and
• S. Alex Kandel

Beilstein J. Nanotechnol. 2017, 8, 1801–1807, doi:10.3762/bjnano.8.181

• polymorphs of the bulk crystal structure [21]. Additionally, the asymmetry of the phenanthrene ring should allow for the determination of the molecular orientation during scanning tunneling microscopy experiments. This molecule has been studied in the past for its role in surface passivation of semiconductor

• resemble the reported bulk crystalline structures. For some polymorphs, these rows line up exactly such that the molecule is oriented in the direction of the row propagation, while the other reported polymorphs have the molecular orientation offset such that there is a tilt of the molecule relative to the

Fluorination of vertically aligned carbon nanotubes: from CF₄ plasma chemistry to surface functionalization

• Claudia Struzzi,
• Mattia Scardamaglia,
• Jean-François Colomer,
• Alberto Verdini,
• Luca Floreano,
• Rony Snyders and
• Carla Bittencourt

Beilstein J. Nanotechnol. 2017, 8, 1723–1733, doi:10.3762/bjnano.8.173

• distribution is independent from the molecular orientation. The structural changes as a result of functionalization are evaluated by Raman spectroscopy. The Raman spectra are collected using a Senterra Bruker micro-Raman system spectrometer with a laser wavelength of 532 nm as excitation source. The micro

Charge transfer from and to manganese phthalocyanine: bulk materials and interfaces

• Florian Rückerl,
• Daniel Waas,
• Bernd Büchner,
• Martin Knupfer,
• Dietrich R. T. Zahn,
• Francisc Haidu,
• Torsten Hahn and
• Jens Kortus

Beilstein J. Nanotechnol. 2017, 8, 1601–1615, doi:10.3762/bjnano.8.160

• in the core-level region, and polarization-dependent studies have often been carried out to study the molecular orientation on substrates. In addition to our experiments we performed calculations within the density functional theory (DFT) framework. We used a recent version of the NRLMOL all-electron

Spin-chemistry concepts for spintronics scientists

• Konstantin L. Ivanov,
• Alexander Wagenpfahl,
• Carsten Deibel and
• Jörg Matysik

Beilstein J. Nanotechnol. 2017, 8, 1427–1445, doi:10.3762/bjnano.8.143

• reaction yield on the field strength, but also on the molecular orientation [91], for instance due to the anisotropy of the hyperfine interaction. The orientation dependence is of importance in solids, since in liquids molecules usually tumble so fast that anisotropic spin interactions are averaged out and

Energy-level alignment at interfaces between manganese phthalocyanine and C₆₀

• Daniel Waas,
• Florian Rückerl,
• Martin Knupfer and
• Bernd Büchner

Beilstein J. Nanotechnol. 2017, 8, 927–932, doi:10.3762/bjnano.8.94

• -level alignment has been demonstrated. For instance, at the interface between CuPc and F16CuPc a significant change in the ionization potential and work function due to the molecular orientation was observed [54]. Also, the orientation of phthalocyanine molecules has been used to influence the C60

• -level alignment as the ionization depends on the molecular orientation in the layers [53]. Finally, comparing our results to those from an associated measurement of co-evaporated mixtures of MnPc and C60 [59] one can find many similarities. The behavior of the valence-band features upon changing the

Triptycene-terminated thiolate and selenolate monolayers on Au(111)

• Jinxuan Liu,
• Martin Kind,
• Björn Schüpbach,
• Daniel Käfer,
• Stefanie Winkler,
• Wenhua Zhang,
• Andreas Terfort and
• Christof Wöll

Beilstein J. Nanotechnol. 2017, 8, 892–905, doi:10.3762/bjnano.8.91

• procedure considering the incident photon flux by division by a spectrum of a clean, freshly sputtered Au substrate. The energy was scaled using the signal of a carbon contamination of a gold grid with a characteristic peak at 284.81 eV. To obtain the molecular orientation of the thiolates/selenolates

Controlled supramolecular structure of guanosine monophosphate in the interlayer space of layered double hydroxide

• Gyeong-Hyeon Gwak,
• Istvan Kocsis,
• Yves-Marie Legrand,
• Mihail Barboiu and
• Jae-Min Oh

Beilstein J. Nanotechnol. 2016, 7, 1928–1935, doi:10.3762/bjnano.7.184

• hybrid obtained at lower temperature was approximately 17.7 Å, which was 5.1 Å larger than for the single molecular orientation. Similar to the GMP adsorption at 80 °C, GMP uptake at 20 °C followed a Langmuir model. Although the Langmuir adsorption rate at 20 °C was slightly smaller than 80 °C, the

• overall adsorption patterns at the two temperatures were similar. Thus, the different interlayer space of GL hybrids at two different temperatures is thought to originate from interlayer molecular orientation of GMP. It is well known that guanosine moieties including GMP form various supramolecular

• molecular orientation of GMPs. According to thermogravimetric analysis (TGA) and X-ray fluorescence (XRF) spectroscopy, the chemical formula of GL-S and GL-R were determined to be Mg2.00Al(OH)6(GMP)0.37(NO3)0.26·(H2Ointerlayer)(0.63H2Osurface) and Mg2.00Al(OH)6(GMP)0.42(NO3)0.16·(H2Ointerlayer

Scanning probe microscopy studies on the adsorption of selected molecular dyes on titania

• Jakub S. Prauzner-Bechcicki,
• Lukasz Zajac,
• Piotr Olszowski,
• Res Jöhr,
• Antoine Hinaut,
• Thilo Glatzel,
• Bartosz Such,
• Ernst Meyer and
• Marek Szymonski

Beilstein J. Nanotechnol. 2016, 7, 1642–1653, doi:10.3762/bjnano.7.156

• . However, the local molecular orientation of PTCDI molecules on the TiO2(110) surface only partially resembles that observed for PTCDA molecules [28][35]. The long molecular axis in case of both PTCDI and PTCDA is parallel to the [001] direction. Yet, the molecular plane of PTCDI is tilted by an angle of

Correlative infrared nanospectroscopic and nanomechanical imaging of block copolymer microdomains

• Benjamin Pollard and
• Markus B. Raschke

Beilstein J. Nanotechnol. 2016, 7, 605–612, doi:10.3762/bjnano.7.53

• enables IR spectroscopy on the nanoscale using broadband [3][4] or tunable light sources [5]. Combined with computational imaging to analyze spectral peak position and lineshape, as well as polarization selection, s-SNOM can probe intermolecular coupling [6], polymorphism [7], molecular orientation