Abstract A semiempirical addition of dispersive forces to conventional density functionals (DFT‐D) has been implemented into a pseudopotential plane‐wave code. Test calculations on the benzene dimer reproduced results obtained by using localized basis set, provided that latter are corrected for set superposition error. By applying DFT‐D/plane‐wave approach substantial agreement with experiments is found structure and energetics polyethylene graphite, two typical solids badly described...

We report on a stepwise on-surface polymerization reaction leading to oriented graphene nanoribbons Au(111) as the final product. Starting from precursor 4,4″-dibromo-p-terphenyl and using Ullmann coupling followed by dehydrogenation C–C coupling, we have developed fine-tuned, annealing-triggered that allows us obtain an nanomesh of via two well-defined intermediate products, namely, p-phenylene oligomers with reduced length dispersion ordered submicrometric molecular wires...

Ultrathin ordered titanium oxide films on Pt(111) surface are prepared by reactive evaporation of Ti in oxygen. By varying the dose and annealing conditions (i.e., temperature oxygen pressure), six different long-range phases obtained. They characterized means low-energy electron diffraction (LEED), X-ray photoemission spectroscopy (XPS), scanning tunneling microscopy (STM). careful optimization preparative parameters, we find where predominantly single TiOx, revealing distinct LEED pattern...

The surface-assisted synthesis of gold-organometallic hybrids on the Au(111) surface both by thermo- and light-initiated dehalogenation bromo-substituted tetracene is reported. Combined X-ray photoemission (XPS) scanning tunneling microscopy (STM) data reveal a significant increase order when mild reaction conditions are combined with 405 nm light irradiation.

Abstract Supercapacitors and transistors are two key devices for future electronics that must combine portability, high performance, easy scalability, etc. Graphene‐related materials (GRMs) frequently chosen as active these applications given their unique physical properties tunable via chemical functionalization. Up to date, among GRMs, only reduced graphene oxide (rGO) showed sufficient versatility processability in mild media, rendering it suitable integration types of devices. Here, a...

Single- and multi-boron, nitrogen, sulphur doped graphene oxide quantum dots three-dimensional foams are synthesized by a simple environmentally friendly electrochemical method.

Epitaxial ${\mathrm{VO}}_{2}$ layers have been grown on the ${\mathrm{TiO}}_{2}$(110) rutile surface up to thicknesses of 5 ML. These ultrathin films characterized by means x-ray photoelectron spectroscopy (XPS), diffraction (XPD), low-energy electron (LEED), and ultraviolet (UPS) measurements. LEED XPD structural data demonstrate that layer is both short- long-range ordered, it has a structure. The success in preparation single-crystalline epitaxial opens possibilities for studying...

A bottom-up route towards the synthesis of titania nanosheets is explored, alternative to exfoliation layered titanates. Nanosheets are assembled from constituent elements and epitaxially matched a suitable substrate: (1 x 2)-Pt(110). Their basic lepidocrocite structure modulated at nanoscale due coincidence with substrate. Density functional calculations reveal details nanosheet, which also shown be in close relationship (001)-oriented anatase bilayer.

The tunable properties of molecular materials place them among the favorites for a variety future generation devices. In addition, to maintain current trend miniaturization those devices, departure from present top-down production methods may soon be required and self-assembly appears most promising alternatives. On-surface synthesis unites promises self-assembly, with sturdiness covalently bonded structures: an ideal scenario applications. Following this idea, we report functional extended...

On-surface synthesis involving the homocoupling of aryl-alkynes affords buildup bisacetylene derivatives directly at surfaces, which in turn may be further used as ingredients for production novel functional materials. Generally, terminal alkynes takes place by thermal activation molecular precursors on metal surfaces. However, interaction with surface atoms often induces unwanted reaction pathways when energy is provided to system. In this contribution we report about light-induced...

Iron(II) phthalocyanine (FePc) self-assembly on Ag(110) has been studied in ultrahigh-vacuum conditions at room temperature by means of scanning tunneling microscopy (STM) and density functional theory (DFT) calculations. For submonolayer to monolayer coverage, FePc molecules lie parallel the surface, arranged rows running along [001] direction. Two similar yet distinct ordered phases are formed, c(10 × 4) p(10 superstructures. The latter is characterized two equivalent equilibrium...

Abstract We explore a photochemical approach to achieve an ordered polymeric structure at the sub‐monolayer level on metal substrate. In particular, tetraphenylporphyrin derivative carrying para ‐amino‐phenyl functional groups is used obtain extended and highly molecular wires Ag(110). Scanning tunneling microscopy density theory calculations reveal that porphyrin building blocks are joined through azo bridges, mainly as cis isomers. The observed stereoselective growth result of...

The challenge of synthesizing graphene nanoribbons (GNRs) with atomic precision is currently being pursued along a one-way road, based on the synthesis adequate molecular precursors that react in predefined ways through self-assembly processes. synthetic options for GNR generation would multiply by adding new direction to this readily successful approach, especially if both them can be combined. We show here how guided an adequately nanotemplated substrate instead traditionally designed...

A novel two-step bottom-up approach to construct a 2D long-range ordered, covalently bonded fullerene/porphyrin binary nanostructure is presented: in the first place, reversible supramolecular interactions between C60 and 5,15-bis(4-aminophenyl)-10,20-diphenylporphyrin are exploited obtain large domains of an ordered network, subsequently reaction fullerene molecules amino-groups residing on porphyrin units, triggered by thermal treatment, used freeze with covalent bonds. The resulting...

Abstract Gold is an inert noble metal displaying superior chemical stability that renders it a suitable component for the manufacturing of electrodes various types devices. Despite being widely employed, variation gold surface properties occurring upon material's exposure to ambient conditions have been often disregarded. While well‐known contamination metallic can dramatic impact on its properties, process itself poorly understood. Changes work function by fractions electron‐volt are...

A surface stabilized monolayer phase of nickel oxide, c(4 × 2)-Ni3O4, has been found to grow epitaxially under reactive deposition conditions on Pd(100), in the presence other adsorbed phases and competition with them. High-quality scanning tunneling microscopy data are reported discussed, including a detailed analysis defects border morphology this new phase. The discussed light ab initio simulations electronic, energetic, geometric properties such hybrid-exchange density functional theory...

Sz\"oke's concept for electron holography is hampered by forward scattering that dominates diffraction from point sources below the surface top layer. Forward was proposed to be suppressed if anisotropic nature of source wave exploited [T. Greber and J. Osterwalder, Chem. Phys. Lett. 256, 653 (1996)]. Experiments show a strong suppression in Al(111) Al $2s$ photoelectrons $({E}_{\mathrm{kin}}\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}952\mathrm{eV})$ are measured near nodal plane...

Periodic density functional calculations have been used to investigate the structure and stability of epitaxial vanadium oxide films grown on TiO(2)(001) anatase surface. The formation energy V(2)O(5) stoichiometry, initially low, is found rapidly increase with film thickness, at variance what obtained for reduced pseudomorphic VO(2) films. This in tune results oxygen-assisted molecular beam epitaxy. oxidation thick, viz. >2 monolayers (ML), yields a c(2 x 2) reconstructed surface, agreement...

The structure of two ordered stoichiometric TiO(2) nanophases supported on Pt(111) and (1x2)-Pt(110) substrates, prepared by reactive evaporation Ti in a high-oxygen background, is compared discussing experimental data (i.e. low-energy electron diffraction, scanning tunneling microscopy) density functional theory calculations. Two rectangular phases, called rect-TiO(2) rect'-TiO(2) were obtained both the hexagonal generally suggesting that they are weakly interacting with substrates. phase...

The combined use of NEXAFS spectroscopic data and DFT results on TM(acac)₃(TM = Cr, Mn, Fe) allowed us to look into the TM–ligand bonding scheme rationalize peculiar electronic structural properties title complexes.

The unoccupied electronic structure of thick films tetraphenylporphyrin and tetrakis(pentafluorophenyl)porphyrin Cu(ii) complexes (hereafter, CuTPP CuTPP(F)) deposited on Au(111) has been studied by combining the outcomes near-edge X-ray absorption fine (NEXAFS) spectroscopy with those spin-unrestricted time-dependent density functional (TD-DFT) calculations carried out either within scalar relativistic zeroth order regular approximation (ZORA) framework (C, N F K-edges) or using...

The rise of graphene as an innovative electronic material promoted the study and development new 2-D materials. Among them, reduced oxide (rGO) appears like easy cost-effective solution for fabrication thin-film transistors (TFTs). To understand limits possible application fields rGO-based TFTs, a proper estimation device parameters is extreme importance. In this work, liquid-gated ambipolar rGO-TFTs are characterized description their working principle given. Particular attention paid...

This paper reports experimental evidence for an incipient epitaxial growth of vanadium oxide at the ${\mathrm{TiO}}_{2}$(110) surface. finding is based on a x-ray photoelectron diffraction and low-energy electron study submonolayer deposited surface, performed after annealing 473 K in ultrahigh vacuum conditions. The data unambiguously show that atoms occupy selected sixfold-coordinated titanium sites which underbridge oxygen topmost layer long-range surface structural order preserved....