Electron interaction with copper(II) carboxylate compounds

• Michal Lacko,
• Peter Papp,
• Iwona B. Szymańska,
• Edward Szłyk and
• Štefan Matejčík

Beilstein J. Nanotechnol. 2018, 9, 384–398, doi:10.3762/bjnano.9.38

• investigated molecules as the highest unoccupied molecular orbital of the studied complexes has Cu–N and Cu–O antibonding character. For all complexes, formation of the Cu2(O2CC2F5)4−• anion is observed together with mononuclear DEA fragments Cu(O2CC2F5)3−, Cu(O2CC2F5)2− and Cu(O2CC2F5)−•. All dominant DEA

• , we can suppose that the lowest unoccupied molecular orbital (LUMO) of the measured complexes has an antibonding character and consists from d-orbitals on Cu atoms, and p-orbitals from the corresponding O atoms. However, Figure 7 shows a difference in the relative intensity of Cu(O2CC2F5)2− ion formed

The rational design of a Au(I) precursor for focused electron beam induced deposition

• Ali Marashdeh,
• Thiadrik Tiesma,
• Niels J. C. van Velzen,
• Sjoerd Harder,
• Remco W. A. Havenith,
• Jeff T. M. De Hosson and
• Willem F. van Dorp

Beilstein J. Nanotechnol. 2017, 8, 2753–2765, doi:10.3762/bjnano.8.274

• . The bond between Au (or any other transition metal) and CO is historically explained by the synergistic backbonding model (Figure 3a) [53]. The free electron pair of the C atom can be donated into an empty orbital of the metal. Vice versa, electrons from partially filled d-orbitals can be donated back

• into the empty π*-orbital of CO, which has the right symmetry for overlap. The C→metal donor bond lowers the electron density from a molecular orbital that is slightly C–O anti-bonding and leads to a strengthening of the C–O bond and a shift of the C–O stretching frequency in the infrared spectrum from

• 2143 cm−1 (free CO) to higher values [54]. On the other hand, backbonding increases the electron density in the π*(C–O) orbital and causes a weakening of the C–O bond, which results in lower C–O stretching frequencies in the infrared spectrum. Since CO complexes generally show absorptions at lower

Inelastic electron tunneling spectroscopy of difurylethene-based photochromic single-molecule junctions

• Youngsang Kim,
• Safa G. Bahoosh,
• Dmytro Sysoiev,
• Thomas Huhn,
• Fabian Pauly and
• Elke Scheer

Beilstein J. Nanotechnol. 2017, 8, 2606–2614, doi:10.3762/bjnano.8.261

• , including the energy of the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) and their coupling to electrodes. This behavior results in a change of the charge transport properties of the corresponding molecular junctions, most prominently of the electrical

Interactions of low-energy electrons with the FEBID precursor chromium hexacarbonyl (Cr(CO)₆)

• Jusuf M. Khreis,
• João Ameixa,
• Filipe Ferreira da Silva and
• Stephan Denifl

Beilstein J. Nanotechnol. 2017, 8, 2583–2590, doi:10.3762/bjnano.8.258

• electron should occupy the lowest unoccupied molecular orbital (LUMO) 9a1g with sigma character [19], or one of the higher-lying virtual molecular orbitals. The ion yields for the detected anionic species are in agreement with Pignataro and co-workers [20]. The dissociative channels described in this study

• the metastable decay in the FF1 is observed at a lower energy than the first maximum of the prompt Cr(CO)4− yield. This may indicate that the electron is captured in an orbital that does not lead to a stable Cr(CO)4− ion detectable in the time window of the mass spectrometer. The anions formed by

• than the one leading to the prompt dissociation. The decay in the FF2 leading to Cr(CO)2− (peaking at ca. 8.5 eV) may involve the same orbital like for prompt decay in Cr(CO)2−. Moreover, the peak close to 8.5 eV is common to both anionic species promptly formed in the ion source and appears in the

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

• between electron correlation, spin–orbital coupling and the on-site Coulomb repulsion [13]. The activation barriers to switch between the three non-ideal conformations have been calculated (free molecules in vacuum) by using the nudged elastic band (NEB) method [14][15] (Figure 2). The barriers between

• contributes to electronic states around the Fermi level. We compare here the spin-resolved density of states projected (PDOS) onto the d-orbitals of Fe in the HS state before and after adsorption (with FeTPP adsorbed at the fcc site of Au(111) surface) (Figure 7). In these cases, only one orbital () is doubly

Laser-assisted fabrication of gold nanoparticle-composed structures embedded in borosilicate glass

• Nikolay Nedyalkov,
• Mihaela Koleva,
• Nadya Stankova,
• Rosen Nikov,
• Mitsuhiro Terakawa,
• Yasutaka Nakajima,
• Lyubomir Aleksandrov and
• Reni Iordanova

Beilstein J. Nanotechnol. 2017, 8, 2454–2463, doi:10.3762/bjnano.8.244

• types of defects: an unpaired electron in the sp3 orbital of a single silicon atom with an oxygen vacancy, and a hole trapped in an oxygen vacancy. The defects that absorb in the visible spectral range are related to nonbridging oxygen hole centers. Since the glass samples used in this study contain

Robust procedure for creating and characterizing the atomic structure of scanning tunneling microscope tips

• Sumit Tewari,
• Koen M. Bastiaans,
• Milan P. Allan and
• Jan M. van Ruitenbeek

Beilstein J. Nanotechnol. 2017, 8, 2389–2395, doi:10.3762/bjnano.8.238

• structure of the tip apex behind the apex atom. Some studies have been carried out to determine the angular orbital symmetry [21][22] of the front atom of the tip apex by making force gradient images of a CO molecule over a Cu(111) substrate. The images are made with a tungsten tip in non-contact AFM

Dissociative electron attachment to coordination complexes of chromium: chromium(0) hexacarbonyl and benzene-chromium(0) tricarbonyl

• Janina Kopyra,
• Paulina Maciejewska and
• Jelena Maljković

Beilstein J. Nanotechnol. 2017, 8, 2257–2263, doi:10.3762/bjnano.8.225

• electrons and accordingly are diamagnetic. For such compounds, it has been postulated that DEA leads exclusively to the formation of fragment negative ions [26], without formation of parent anions, since the captured electron has to occupy an antibonding molecular orbital. In accordance with the predictions

• orbital (MO). On the other hand, core excited resonances occur when the incoming electron transfers its energy to electronically excite the target molecule and hence becomes captured by the electron–molecule potential of the excited state. Electron attachment to Cr(CO)6 leads, under the current

• be attributed to a negative ion state emerging from electron capture into the 3t2g orbital of this molecule [30]. A high cross section for the [Cr(CO)5]− ion formation already at energy close to 0 eV implies that the reaction is most likely exothermic, i.e., the electron affinity of the Cr(CO)5

Comprehensive investigation of the electronic excitation of W(CO)₆ by photoabsorption and theoretical analysis in the energy region from 3.9 to 10.8 eV

• Mónica Mendes,
• Khrystyna Regeta,
• Filipe Ferreira da Silva,
• Nykola C. Jones,
• Søren Vrønning Hoffmann,
• Gustavo García,
• Chantal Daniel and
• Paulo Limão-Vieira

Beilstein J. Nanotechnol. 2017, 8, 2208–2218, doi:10.3762/bjnano.8.220

• range of 125–350 nm [1][2][3][4][5], and electron energy loss [6][7][8], photoelectron [9][10], photoionisation [11] and electron momentum [12][13] spectroscopy. In theoretical studies, Dirac-scattered-wave (DSW) calculations [14], molecular orbital energy level calculations [2], relativistic time

• occupied molecular orbital (HOMO), 4t2g, has metal dπ character, the second-highest molecular orbital (HOMO−1), 11t1u, has σCO character, the third-highest (HOMO−2), 1t1g, and the fourth-highest occupied molecular orbitals (HOMO−3), 3t2g, have CO character. The lowest unoccupied molecular orbital (LUMO

• assigned to a symmetry-forbidden feature. Rosa and co-workers [15] have proposed that in the region of 3.5–4.0 eV spin-allowed but symmetry-forbidden charge-transfer transitions as well as spin-forbidden but orbital-allowed 1A1g→a,b3T1u transitions occur. The present calculations including SOC effects show

Electronic structure, transport, and collective effects in molecular layered systems

• Torsten Hahn,
• Tim Ludwig,
• Carsten Timm and
• Jens Kortus

Beilstein J. Nanotechnol. 2017, 8, 2094–2105, doi:10.3762/bjnano.8.209

• . Further studies indicated that the Co orbital is filled due to the charge transfer at the interface to MnPc. Experiments and theory showed that a bulk material can be formed that maintains the charge and spin transfer between the two molecules [12]. Similar observations were made for organic molecules

• where creates an electron in the molecular orbital ν with spin σ and single-particle energy eν, is the corresponding number operator, and is its spin operator in terms of the vector of Pauli matrices, σ. Uν and Uνν' = Uν'ν describe the intraorbital and interorbital Coulomb interactions, respectively

• , and Jνν' = Jν'ν is the Hund-rule coupling. The orbital energies eν are shifted by the electric potential, which is controlled by the bias voltage V = (μT − μS)/e. The eigenenergies and eigenstates of Hmol satisfy Only the differences between molecule and electrode energies enter the final results and

High-stress study of bioinspired multifunctional PEDOT:PSS/nanoclay nanocomposites using AFM, SEM and numerical simulation

• Alfredo J. Diaz,
• Hanaul Noh,
• Tobias Meier and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 2069–2082, doi:10.3762/bjnano.8.207

• Free Electron Orbital Theory (PFEO) is a simple and useful tool for describing the energy levels for small conjugated molecules, so it is adopted for this analysis. In this model, the delocalized π electrons are treated as free electrons traveling in a loop around the conjugated molecular perimeter [69

Coexistence of strongly buckled germanene phases on Al(111)

• Weimin Wang and
• Roger I. G. Uhrberg

Beilstein J. Nanotechnol. 2017, 8, 1946–1951, doi:10.3762/bjnano.8.195

• -like structures formed by the group IV atoms Si, Ge and Sn, i.e., silicene, germanene and stanene. However, Si, Ge, and Sn atoms prefer sp3 hybridization, resulting in a buckled honeycomb structure with a mixture of sp2-sp3 character [1][2][3]. As a result, the spin-orbital coupling is enlarged and the

Spin-dependent transport and functional design in organic ferromagnetic devices

• Guichao Hu,
• Shijie Xie,
• Chuankui Wang and
• Carsten Timm

Beilstein J. Nanotechnol. 2017, 8, 1919–1931, doi:10.3762/bjnano.8.192

• phenomenon is explained by transmission and orbital analysis. These works show that organic ferromagnets are promising components for spintronic devices that deserve to be designed and examined in future experiments. Keywords: magnetoresistance; organic ferromagnet; spin-current rectification; spin

• hyperfine interactions in organic materials are usually weak [4], which induces a long spin relaxation time and makes organic materials ideal for spin-polarized transport applications. Organic molecules may form a soft interface with metals and ferromagnets via chemical adsorption. The interfacial orbital

• /π)Im[Gσσ(E,V)]. The result for 0.8 V is shown in Figure 3. Evidently, the DOS is spin-split due to the coupling with radical spins. An energy gap of about 1.0 eV appears between the spin-down highest occupied molecular orbital (HOMO) and the spin-up lowest occupied molecular orbital (LUMO). For a

Optical techniques for cervical neoplasia detection

• Tatiana Novikova

Beilstein J. Nanotechnol. 2017, 8, 1844–1862, doi:10.3762/bjnano.8.186

• match a possible electronic transition within the molecule. Consequently, part of incident radiation will be absorbed as the electron is lifted to a higher energy orbital. During de-excitation (return of electron to the ground state) those molecules release energy in the form of light of a specific

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

• possible [43][45][46]. The EELS cross section is proportional to Im(−1/ε) (ε is the dielectric function). In this way, one can investigate valence-band excitations (cf. optical methods) and the element-projected unoccupied density of states. Also, access to orbital selective occupations and the magnetic

• DFT code [51][52], which uses large Gaussian-orbital basis sets for the representation of the electronic wavefunctions [53]. Unless noted otherwise we used the PBE functional [54] within the general gradient approximation (GGA) was used for all calculations. We semi-empirically included dispersion

• usually ascribed to the Q band common to many phthalocyanines [57][58][59]. They are due to transitions from the highest occupied molecular orbital (HOMO) to the lowest unoccupied molecular orbital (LUMO) [58]. The observed fine structure was attributed to a combination of Davydov splitting, the admixture

Two-dimensional carbon-based nanocomposites for photocatalytic energy generation and environmental remediation applications

• Suneel Kumar,
• Ashish Kumar,
• Ashish Bahuguna,
• Vipul Sharma and
• Venkata Krishnan

Beilstein J. Nanotechnol. 2017, 8, 1571–1600, doi:10.3762/bjnano.8.159

• formed by the anti-bonding π* orbital which has a higher energy level of −0.52 eV. Thus, due to the more negative anti-bonding π* orbital, which is needed for hydrogen generation, GO can act as a photocatalyst. Also, the VB edge of GO is mainly composed of O 2p orbitals and may not be positive enough to

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

• of a long molecule. If the two radicals are on the same molecule and close together, they need to be in different orbitals, mostly one is in the highest occupied and the other in the lowest unoccupied molecular orbital. In this case, a molecular triplet state can occur (3R••). A pair of two radicals

Adsorption and electronic properties of pentacene on thin dielectric decoupling layers

• Sebastian Koslowski,
• Daniel Rosenblatt,
• Alexander Kabakchiev,
• Klaus Kuhnke,
• Klaus Kern and
• Uta Schlickum

Beilstein J. Nanotechnol. 2017, 8, 1388–1395, doi:10.3762/bjnano.8.140

• divergence from the aforementioned trend for the orbital energies of pentacene deposited onto h-BN/Rh(111), as well as in the different adsorption geometry. Thus, the highly desirable capacity of h-BN to trap molecules comes at the price of enhanced metal–molecule interaction, which decreases the HOMO–LUMO

• demonstrated by the observation of the unperturbed gas-phase-like frontier orbitals of pentacene on this substrate [3]. A weak interaction is nevertheless suggested by the observed shift of the orbital energies of the admolecule [4][7][8]. In scanning tunneling spectroscopy (STS) experiments on pentacene, two

• therefore also referred to as the positive- and negative-ion resonances (PIR and NIR). The NIR corresponds to the highest occupied molecular orbital (HOMO) and the PIR to the lowest unoccupied molecular orbital (LUMO). Various thin insulating layers have so far been used as decoupling layers in STM

Adsorption characteristics of Er₃N@C₈₀on W(110) and Au(111) studied via scanning tunneling microscopy and spectroscopy

• Sebastian Schimmel,
• Zhixiang Sun,
• Danny Baumann,
• Denis Krylov,
• Nataliya Samoylova,
• Alexey Popov,
• Bernd Büchner and
• Christian Hess

Beilstein J. Nanotechnol. 2017, 8, 1127–1134, doi:10.3762/bjnano.8.114

• further, we performed scanning tunneling spectroscopy (STS) on the Er3N@C80-monolayer on Au(111). The obtained spectroscopic results, presented in Figure 4, exhibit two dominant peaks related to the HOMO- and LUMO-derived states (HDS and LDS) (Figure 4b). In between the molecular orbital derived states

Analysis and modification of defective surface aggregates on PCDTBT:PCBM solar cell blends using combined Kelvin probe, conductive and bimodal atomic force microscopy

• Hanaul Noh,
• Alfredo J. Diaz and
• Santiago D. Solares

Beilstein J. Nanotechnol. 2017, 8, 579–589, doi:10.3762/bjnano.8.62

• energy level of either the lowest unoccupied molecular orbital (LUMO) or the highest occupied molecular orbital (HOMO) of PCDTBT and PCBM, and E is the biased Fermi energy of either the electron or hole at the Pt tip and the PEDOT:PSS. Since the measured currents in C-AFM are related to the transmission

Association of aescin with β- and γ-cyclodextrins studied by DFT calculations and spectroscopic methods

• Ana I. Ramos,
• Pedro D. Vaz,
• Susana S. Braga and
• Artur M. S. Silva

Beilstein J. Nanotechnol. 2017, 8, 348–357, doi:10.3762/bjnano.8.37

• GACZIT [38]). A similar simulation strategy has been adopted by some of us previously to address accurate geometries and energies of organic molecules [39]. NMR shielding tensors were calculated using the gauge-independent atomic orbital method (GIAO) [40][41][42][43][44] with the same functional

Colorimetric gas detection by the varying thickness of a thin film of ultrasmall PTSA-coated TiO₂ nanoparticles on a Si substrate

• Urmas Joost,
• Andris Šutka,
• Meeri Visnapuu,
• Aile Tamm,
• Meeri Lembinen,
• Mikk Antsov,
• Kathriin Utt,
• Krisjanis Smits,
• Ergo Nõmmiste and
• Vambola Kisand

Beilstein J. Nanotechnol. 2017, 8, 229–236, doi:10.3762/bjnano.8.25

• excited-state energies using the same calculation parameters as for the ground state, and adding a local combination of atomic orbital modes. The crystalline phases of the titania NPs were examined by measuring room-temperature Raman spectra of the films prepared on a fused silica substrate using a

Ordering of Zn-centered porphyrin and phthalocyanine on TiO₂(011): STM studies

• Piotr Olszowski,
• Lukasz Zajac,
• Szymon Godlewski,
• Bartosz Such,
• Rémy Pawlak,
• Antoine Hinaut,
• Res Jöhr,
• Thilo Glatzel,
• Ernst Meyer and
• Marek Szymonski

Beilstein J. Nanotechnol. 2017, 8, 99–107, doi:10.3762/bjnano.8.11

• role, the mechanism involved in such an interaction was concerned with the specific p–d orbital coupling between the localized Si substrate pz states on the B-passivated Si(111) surface and the metal atom at the center of the flat laying phthalocyanine molecule. This type of mechanism is not applicable

Effect of Anderson localization on light emission from gold nanoparticle aggregates

• Mohamed H. Abdellatif,
• Marco Salerno,
• Gaser N. Abdelrasoul,
• Ioannis Liakos,
• Alice Scarpellini,
• Sergio Marras and
• Alberto Diaspro

Beilstein J. Nanotechnol. 2016, 7, 2013–2022, doi:10.3762/bjnano.7.192

• hybridization of the orbitals in the AuNPs. The plasmon hybridization theory [19] is used to predict the atomic orbital interactions. The hybridized plasmon produced here results in the splitting of the plasmonic resonance into a higher energy antisymmetric plasmon mode and a lower energy symmetric mode. The

Zigzag phosphorene nanoribbons: one-dimensional resonant channels in two-dimensional atomic crystals

• Carlos. J. Páez,
• Dario. A. Bahamon,
• Ana L. C. Pereira and
• Peter. A. Schulz

Beilstein J. Nanotechnol. 2016, 7, 1983–1990, doi:10.3762/bjnano.7.189

• to the Fermi energy, hinders a wider use of single-orbital tight-binding models in chasing the alluded electronic and transport properties of systems based on this new material. Nevertheless, the use of such model is well validated, by means of comparisons with first-principle electronic structure

• are described by s-like orbital chain models. The positions of the transmission resonances are shown in Figure 5 to be well reproduced by a simple one-dimensional double-barrier quantum well modeled by a chain of s-like orbitals [32][33]. The nearest neighbor hopping (t1D) of the one-dimensional chain