The influence of an interfacial hBN layer on the fluorescence of an organic molecule

• Christine Brülke,
• Oliver Bauer and
• Moritz M. Sokolowski

Beilstein J. Nanotechnol. 2020, 11, 1663–1684, doi:10.3762/bjnano.11.149

• system of this work, namely, 3,4,9,10-perylene tetracarboxylic dianhydride (PTCDA) on a layer of hBN on Cu(111). Here, we consider an S1 excitation which involves mainly a HOMO/LUMO (highest occupied and lowest unoccupied molecular orbital) electronic excitation. Rapid CT leads to a delocalization of the

PTCDA adsorption on CaF₂ thin films

• Philipp Rahe

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

• observed at this bias voltage with an orbital structure in Figure 2e that is different from the filled-state image in Figure 2b. One example of a constant-height STM image acquired at a negative sample bias of −3 V on the CaF2/CaF1Si(111) thick film is shown in Figure 2c and reveals a striped structure of

• main finding is electron accumulation below the carbonyl oxygen atoms, in agreement with the attractive interaction with the surface calcium atom already identified before from the oxygen displacement. Isosurfaces of the molecular orbital densities of the highest occupied molecular orbital (HOMO) as

• well as the three lowest unoccupied molecular orbitals (LUMO, LUMO+1, and LUMO+2) as calculated with cp2k for the PTCDA/CaF2(111) system are depicted in Figure 4e–h. The orbital shapes largely resemble earlier calculations of a flat PTCDA molecule in the gas phase [10], although the LUMO+1 and LUMO+2

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

• the BOSS runs, to relax the predicted stable structures and to analyze the electronic structure of the stable adsorbates. We apply the all-electron, numeric atom-centered orbital code FHI-aims [41][42][43] with the Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional [44]. PBE is augmented

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

• : decoupling; integer charge transfer; organic films; para-sexiphenyl; thin dielectric film; Introduction Since the first scanning tunneling microscope (STM) imaging of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) of pentacene (5A) on NaCl/Cu(111) was

• Pacchioni et al. [4][5][6] and either inferred or observed for adsorbates ranging from metal atoms [7][8] and small molecules [9][10] to larger π-conjugated molecules [11][12][13]. This phenomenon has been comprehensively analyzed for 5A on epitaxial MgO(100)/Ag(100), in which orbital-resolved STM and

• photoemission tomography (PT) have enabled the quantification of both the charge on individual molecules and the number of charged molecules in the 5A monolayer (ML) [14]. For 5A MLs on regularly grown epitaxial MgO(100) films, all molecules appear to be charged. Orbital-resolved STM reveals the LUMO both above

Self-assembly and spectroscopic fingerprints of photoactive pyrenyl tectons on hBN/Cu(111)

• Domenik M. Zimmermann,
• Knud Seufert,
• Luka Ðorđević,
• Tobias Hoh,
• Sushobhan Joshi,
• Tomas Marangoni,
• Davide Bonifazi and
• Willi Auwärter

Beilstein J. Nanotechnol. 2020, 11, 1470–1483, doi:10.3762/bjnano.11.130

• as such spacer layers [18] and can promote site-dependent decoupling and adsorption [19][20], yielding access to optical transitions [21] as well as allowing for orbital-resolved STM imaging [19][21][22][23]. For instance, hBN/Cu(111) [24][25][26][27] features a work function template with a moiré

• Figures S1–S5, Supporting Information File 1). The computations revealed that the pyrenes have large orbital coefficients at the 1-, 3-, 6-, and 8-positions, with the nodal plane going through the 2- and 7-positions (Figure 1) [69][70][71][72][73][74]. As a consequence of this spatial distribution, the

• orbital interactions between the pyrene and the pyridin-4-ylethynyl MOs had a stabilizing effect on the highest occupied (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels. While the HOMO stabilization played only a small part, it was the considerable lowering of the LUMO energy levels

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

• physisorptive [29][53]. On Cu(111), PFP shows a behavior close to physisorption [9], although the coupling strength might be slightly stronger than with Au(111) [54]. PEN on Cu(111), however, is strongly chemisorbed, involving a partial filling of the former lowest unoccupied molecular orbital (LUMO) by a

Atomic defect classification of the H–Si(100) surface through multi-mode scanning probe microscopy

• Jeremiah Croshaw,
• Thomas Dienel,
• Taleana Huff and
• Robert Wolkow

Beilstein J. Nanotechnol. 2020, 11, 1346–1360, doi:10.3762/bjnano.11.119

• due to its conductive orbital which extends into vacuum. DBs have been observed to act like quantum dots and have discretized charge states in the bandgap of the material [6]. Due to the degenerate n-type doping of our substrate (see Methods) [6][53], DBs are natively negatively charged when imaging

• the empty states of the surface. This localized negative charge leads to band bending around the DB location at these biases, giving the DB a dark “halo” around the bright orbital protrusion (Figure 2a-1) [53][55]. Filled states imaging (Figure 2a-2) lacks the charge-induced band bending around the DB

Structural and electronic properties of SnO₂ doped with non-metal elements

• Jianyuan Yu,
• Yingeng Wang,
• Yan Huang,
• Xiuwen Wang,
• Jing Guo,
• Jingkai Yang and
• Hongli Zhao

Beilstein J. Nanotechnol. 2020, 11, 1321–1328, doi:10.3762/bjnano.11.116

• ) is mainly due to Sn 5s orbitals, and the O 2p orbital is responsible for the part between −5.8 and 0 eV. The main contributions to the conduction band are from Sn 5s and Sn 5p orbitals. It is worth noting that the energy band of SnO2 changes significantly after doping. B 2p, C 2p, S 3p, and N 2p

• changes clearly, indicating that doping B atoms can adjust the SnO2 bandgap value well. It can be seen from the partial wave state density diagram that the B 2p orbital and the S 3p orbital enter the SnO2 crystal bandgap. After the introduction of F atoms, the Fermi energy level passes through the

Hybridization vs decoupling: influence of an h-BN interlayer on the physical properties of a lander-type molecule on Ni(111)

• Maximilian Schaal,
• Takumi Aihara,
• Marco Gruenewald,
• Felix Otto,
• Jari Domke,
• Roman Forker,
• Hiroyuki Yoshida and
• Torsten Fritz

Beilstein J. Nanotechnol. 2020, 11, 1168–1177, doi:10.3762/bjnano.11.101

• [37]. Within this notation, each feature is ascribed to the involved molecular orbital with the probing process being characterized by the initial state as subscript and the final state as a superscript. For example, a single-photon photoionization (UPS measurement) describes a transition from the

Scanning tunneling microscopy and spectroscopy of rubrene on clean and graphene-covered metal surfaces

• Karl Rothe,
• Alexander Mehler,
• Nicolas Néel and
• Jörg Kröger

Beilstein J. Nanotechnol. 2020, 11, 1157–1167, doi:10.3762/bjnano.11.100

• superstructure characterize the adsorption phase. The highest occupied molecular orbital of C42H28 on Au(111) exhibits weak vibronic progression while unoccupied molecular resonances appear with a broad line shape. In contrast, vibronic subbands are present for both frontier orbitals of C42H28 on graphene. They

• -covered Ir(111) [9] have been reported so far. In these studies molecular orbitals, the highest occupied molecular orbital (HOMO) or the lowest unoccupied molecular orbital (LUMO), appear with spectroscopic fine structure in differential conductance (dI/dV, I: tunneling current, V: bias voltage) data

• spectra of Figure 3 emphasize that a bright (dim) contrast does not necessarily imply a high (low) geometrical distance. The bright lobe of the molecule exhibits a dI/dV spectrum with a single broad orbital feature, which indicates its elevated hybridization with the metal surface rather than its greater

Straightforward synthesis of gold nanoparticles by adding water to an engineered small dendrimer

• Sébastien Gottis,
• Régis Laurent,
• Vincent Collière and
• Anne-Marie Caminade

Beilstein J. Nanotechnol. 2020, 11, 1110–1118, doi:10.3762/bjnano.11.95

• nanoparticle synthesis due to the reactivity of this linkage [37][38][39] and due to its ability to complex metals, especially gold(I), with the sulfur atom [40][41]. A recent theoretical work demonstrated that the highest occupied molecular orbital of a small dendrimer containing the P=N–P=S linkage is

Monolayers of MoS₂ on Ag(111) as decoupling layers for organic molecules: resolution of electronic and vibronic states of TCNQ

• Asieh Yousofnejad,
• Gaël Reecht,
• Nils Krane,
• Christian Lotze and
• Katharina J. Franke

Beilstein J. Nanotechnol. 2020, 11, 1062–1071, doi:10.3762/bjnano.11.91

• unoccupied molecular orbital (LUMO) of tetracyanoquinodimethane (TCNQ) molecules is significantly narrower than on the bare substrate and that it is accompanied by a characteristic satellite structure. Employing simple calculations within the Franck–Condon model, we reveal their vibronic origin and identify

• nature of the substrate [33]. One may thus envision tuning the bandgap alignment for decoupling either the lowest unoccupied (LUMO) or the highest occupied molecular orbital (HOMO) of the molecules. While MoS2 on Au(111) has already been established as an outstanding decoupling layer [26], we will now

• ], this appearance can be associated to the spatial distribution of the lowest unoccupied molecular orbital (LUMO). The molecular arrangement can be described by the lattice vectors a1 = 0.9 ± 0.1 nm, a2 = 1.0 ± 0.1 nm and the angle (96 ± 2)° (see model in Figure 3c). This structure is stabilized by

Adsorption behavior of tin phthalocyanine onto the (110) face of rutile TiO₂

• Lukasz Bodek,
• Mads Engelund,
• Aleksandra Cebrat and
• Bartosz Such

Beilstein J. Nanotechnol. 2020, 11, 821–828, doi:10.3762/bjnano.11.67

• ] with a double-zeta polarized (DZP) basis set and orbital radii defined using an energy shift of 100 meV, a Perdew–Burke–Ernzerhof (PBE) exchange–correlation potential [16] and a real-space grid equivalent to a plane-wave cutoff of 200 Ry. Forces were relaxed until they were smaller than 0.020 eV·Å−1

• molecular orbital (LUMO) calculated for d) a DFT-optimized geometry for a Sn-down molecule influenced by the surface; e) LT-STM image of a Sn-up molecule with f) the corresponding simulated STM image at the LUMO energy level and g) optimized DFT gas-phase geometry. Scanning parameters: a) 3 × 4 nm2, It = 3

Nickel nanoparticles supported on a covalent triazine framework as electrocatalyst for oxygen evolution reaction and oxygen reduction reactions

• Secil Öztürk,
• Yu-Xuan Xiao,
• Dennis Dietrich,
• Beatriz Giesen,
• Juri Barthel,
• Jie Ying,
• Xiao-Yu Yang and
• Christoph Janiak

Beilstein J. Nanotechnol. 2020, 11, 770–781, doi:10.3762/bjnano.11.62

• source (1486.8 eV). The C 1s orbital with a binding energy of 284.8 eV was taken as a reference for the evaluation of the spectra. CasaXPS, version 2.3.19PR1.0, copyright 1999-2018 Casa Software Ltd. program was used for the fit of the experimental XP spectra. Synthesis of CTF-1 CTF-1-400 and CTF-1-600

Interfacial charge transfer processes in 2D and 3D semiconducting hybrid perovskites: azobenzene as photoswitchable ligand

• Nicole Fillafer,
• Tobias Seewald,
• Lukas Schmidt-Mende and
• Sebastian Polarz

Beilstein J. Nanotechnol. 2020, 11, 466–479, doi:10.3762/bjnano.11.38

• energy of the highest occupied molecular orbital (HOMO) of the molecule. In combination with UV–vis measurements the higher unoccupied MOs (S1 and S2) of the molecule can be determined. The data are summarized in Table 2. It is well known, that the S0→S2 transition (a symmetry-allowed π→π* transition) is

Implementation of data-cube pump–probe KPFM on organic solar cells

• Benjamin Grévin,
• Olivier Bardagot and
• Renaud Demadrille

Beilstein J. Nanotechnol. 2020, 11, 323–337, doi:10.3762/bjnano.11.24

• molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels. These energetic offsets enable to dissociate singlet excitons into Coulomb-bound electron–hole pairs also called charge transfer states (CTs). These can either recombine in pairs at the D–A interfaces or split up into free

Nonequilibrium Kondo effect in a graphene-coupled quantum dot in the presence of a magnetic field

• Levente Máthé and
• Ioan Grosu

Beilstein J. Nanotechnol. 2020, 11, 225–239, doi:10.3762/bjnano.11.17

• Keldysh nonequilibrium Green’s function theory by Li and co-workers [67]. They found that the Kondo peak can be observed in a wide parameter range from the Kondo regime to the mixed valence regime or to the empty orbital regime, which is in agreement with the literature [68][69][70]. In the latter two

• the Kondo effect for a carbon vacancy in a monolayer of graphene via an effective two-orbital single impurity model using the NRG approach [74]. Vojta et al. applied the pseudogap Kondo and Anderson models using a combination of analytical and numerical renormalization group approaches to study the

Design and facile synthesis of defect-rich C-MoS₂/rGO nanosheets for enhanced lithium–sulfur battery performance

• Chengxiang Tian,
• Juwei Wu,
• Zheng Ma,
• Bo Li,
• Pengcheng Li,
• Xiaotao Zu and
• Xia Xiang

Beilstein J. Nanotechnol. 2019, 10, 2251–2260, doi:10.3762/bjnano.10.217

•  4c). The two peaks of pristine MoS2 at 228.9 and 232.1 eV in Figure 4d are assigned to binding energies of Mo 3d5/2 and 3d3/2 for Mo4+, respectively, corresponding to the 2H phase of MoS2[20]. The two peaks at 162.78 and 161.7 eV are attributed to the S 2p1/2 and S 2p3/2 orbital of divalent sulfide

First principles modeling of pure black phosphorus devices under pressure

• Ximing Rong,
• Zhizhou Yu,
• Zewen Wu,
• Junjun Li,
• Bin Wang and
• Yin Wang

Beilstein J. Nanotechnol. 2019, 10, 1943–1951, doi:10.3762/bjnano.10.190

• ][34]. In our calculation, norm-conserving non-local pseudo-potentials were used to define the atomic cores [40], and an atomic orbital basis set with single-ζ plus polarization was used to expand physical quantities [41]. The exchange correlation potential was treated using the PBE functional [37][38

Charge-transfer interactions between fullerenes and a mesoporous tetrathiafulvalene-based metal–organic framework

• Manuel Souto,
• Joaquín Calbo,
• Samuel Mañas-Valero,
• Aron Walsh and
• Guillermo Mínguez Espallargas

Beilstein J. Nanotechnol. 2019, 10, 1883–1893, doi:10.3762/bjnano.10.183

• C60@MUV-2 corresponds to the electron-rich TTF unit (Figure 6a). The highest occupied crystal orbital (HOCO) displays the typical shape of the TTF HOMO and confirms the TTF-nature of the VBM (Figure 6b). In the α-channel, the conduction band minimum (CBM) is described by the fullerene moiety, being

• the lowest unoccupied crystal orbital (LUCO) completely localized on the C60 ball. Otherwise, the CBM in the β-channel is best described by the unoccupied Fe d-orbitals of the inorganic cluster of the MOF, the eigenstates corresponding to the fullerene being only 0.2 eV above in energy (Figure 6). Due

Synthesis of nickel/gallium nanoalloys using a dual-source approach in 1-alkyl-3-methylimidazole ionic liquids

• Ilka Simon,
• Julius Hornung,
• Juri Barthel,
• Jörg Thomas,
• Maik Finze,
• Roland A. Fischer and
• Christoph Janiak

Beilstein J. Nanotechnol. 2019, 10, 1754–1767, doi:10.3762/bjnano.10.171

• File 1, Table S2). By using high-resolution X-ray photoelectron spectroscopy (HRXPS), the electron binding energy of the O 1s orbital was measured to confirm that the Ga nanoparticles in both samples are doped with NiGa and not with Ga oxide (Figure 6). The concomitant Ga 2p3/2-peak (Supporting

• (large particles) from a 1 wt % dispersion of Ni(COD)2 and GaCp* in [BMIm][NTf2] after 12 h of dispersion and 30 min of decomposition. SAED with indexed reflections for NiGa (green diffraction rings for space group ) and Ga (yellow diffraction rings for space group Cmce). HRXPS region of the O 1s orbital

Kelvin probe force microscopy work function characterization of transition metal oxide crystals under ongoing reduction and oxidation

• Dominik Wrana,
• Karol Cieślik,
• Wojciech Belza,
• Christian Rodenbücher,
• Krzysztof Szot and
• Franciszek Krok

Beilstein J. Nanotechnol. 2019, 10, 1596–1607, doi:10.3762/bjnano.10.155

• electronic structure between the band insulator SrTiO3 and metallic TiO. Here there are two 3d electrons per one Ti2+ divalent titanium ion, partially filling the metallic d-band in the energy diagram. From the orbital perspective, high conductivity is a consequence of the d-orbital overlap from the

• neighboring Ti sites. In the case of cubic TiO, the Ti–Ti distance is slightly above 2 Å, which is enough to have a significant overlap given the d-orbital extension. On the other hand, in the ideal SrTiO3 perovskite there are no d-electrons on Ti sites. Thus a TiO network on SrTiO3 constitutes a metallic

Graphynes: an alternative lightweight solution for shock protection

• Kang Xia,
• Haifei Zhan,
• Aimin Ji,
• Jianli Shao,
• Yuantong Gu and
• Zhiyong Li

Beilstein J. Nanotechnol. 2019, 10, 1588–1595, doi:10.3762/bjnano.10.154

• of GYs in the field of impact protection such as combat armor and protective shield against orbital debris for spacecraft [22]. Currently, no studies have investigated the performance of GYs under direct impact in literature. However ballistic tests have been conducted both experimentally and

The effect of magneto-crystalline anisotropy on the properties of hard and soft magnetic ferrite nanoparticles

• Hajar Jalili,
• Bagher Aslibeiki,
• Ali Ghotbi Varzaneh and
• Volodymyr A. Chernenko

Beilstein J. Nanotechnol. 2019, 10, 1348–1359, doi:10.3762/bjnano.10.133

• increasing magnetic anisotropy with increasing cobalt content. This is due to the gradual occupation of the octahedral sites by cobalt ions and the stronger LS coupling originating from their strong orbital angular momentum [37][38]. The drop of anisotropy in the x = 0.8 sample might be due to the decrease

Fabrication of phase masks from amorphous carbon thin films for electron-beam shaping

• Lukas Grünewald,
• Dagmar Gerthsen and
• Simon Hettler

Beilstein J. Nanotechnol. 2019, 10, 1290–1302, doi:10.3762/bjnano.10.128

• ; Bessel beam; electron-beam shaping; nanofabrication; vortex beam; Introduction The possibility to shape electron beams has gained much interest since the first observation of electron vortex beams, i.e., beams that carry a defined orbital angular momentum [1][2][3]. Various other beam shapes, e.g., non

• (VBs) are of great interest due to their well-defined orbital angular momentum (OAM) with the topological charge l and the Dirac constant The phase of a VB varies azimuthally upon propagation, where l is equal to the number of turns in the wave front per wavelength [27]. In the center of a VB exists