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15N‐labeled tetrasulfur tetranitride (S415N4) was synthesized by reacting S2Cl2 with 15NH3. The reaction was finalized with 14NH3. The successful labeling was confirmed by solution 15N nuclear magnetic resonance (NMR) spectroscopy. S415N4 was used for the synthesis of poly(sulfur nitride) S15Nx via the intermediate species of S2N2. It was a topochemical polymerization in the solid state. The isotope ratio in the labeled polymer was obtained by laser deposition ionization time‐of‐flight mass spectroscopy. Solid‐state 15N NMR spectroscopy of S15Nx indicates that at least three different chemical environments for 15N atoms are present in the crystals. Finally, SNx was polymerized in the presence of two other superconductors, MgB2 and yttrium barium copper oxide (YBCO), which demonstrates the capability of SNx for grain boundary engineering. [ABSTRACT FROM AUTHOR]

Recent work has produced non-planar carbon-based nanostructures such as fullerenes, carbon pyramids, and buckybowls from their corresponding quasi-planar polycyclic aromatic hydrocarbon precursors through surface-catalysed cyclodehydrogenation (CDH) (19-21). We have extended [...], Over the past two decades, single-walled carbon nanotubes (SWCNTs) have received much attention because their extraordinary properties are promising for numerous applications (1,2). Many of these properties depend sensitively on SWCNT structure, which is characterized by the chiral index (n,m) that denotes the length and orientation of the circumferential vector in the hexagonal carbon lattice. Electronic properties are particularly strongly affected, with subtle structural changes switching tubes from metallic to semiconducting with various bandgaps. Monodisperse 'single-chirality' (that is, with a single (n,m) index) SWCNTs are thus needed to fully exploit their technological potential (1,2). Controlled synthesis through catalyst engineering (3-6), end- cap engineering (7) or cloning strategies (8,9), and also tube sorting based on chromatography (10,11), density-gradient centrifugation, electrophoresis and other techniques (12), have delivered SWCNT samples with narrow distributions of tube diameter and a large fraction of a predetermined tube type. But an effective pathway to truly monodisperse SWCNTs remains elusive. The use of template molecules to unambiguously dictate the diameter and chirality of the resulting nanotube (8,13-16) holds great promise in this regard, but has hitherto had only limited practical success (7,17,18). Here we show that this bottom-up strategy can produce targeted nanotubes: we convert molecular precursors into ultrashort singly capped (6,6) 'armchair' nanotube seeds using surface-catalysed cyclodehydrogenation on a platinum (111) surface, and then elongate these during a subsequent growth phase to produce single-chirality and essentially defect-free SWCNTs with lengths up to a few hundred nanometres. We expect that our on-surface synthesis approach will provide a route to nanotube-based materials with highly optimized properties for applications such as light detectors, photovoltaics, field-effect transistors and sensors (2).

We investigate the gas-phase chemistry of noncovalent complexes of [10]cycloparaphenylene ([10]CPP) with C60 and C70 by means of atmospheric pressure photoionization and electrospray ionization mass spectrometry. The literature-known [1: 1] complexes, namely [10]CPP⊃C60 and [10]CPP⊃C70, are observed as radical cations and anions. Their stability and charge distribution are studied using energy-resolved collision-induced dissociation (ER-CID). These measurements reveal that complexes with a C70 core exhibit a greater stability and, on the other hand, that the radical cations are more stable than the respective radical anions. Regarding the charge distribution, in anionic complexes charges are exclusively located on C60 or C70, while the charges reside on [10]CPP in the case of cationic complexes. [2: 1] complexes of the ([10]CPP2 ⊃C60/70)+ ⋅/- ⋅ type are observed for the first time as isolated solitary gas-phase species. Here, C60 -based [2: 1] complexes are less stable than the respective C70 analogues. By virtue of the high stability of cationic [1: 1] complexes, [2: 1] complexes show a strongly reduced stability of the radical cations. DFT analyses of the minimum geometries as well as molecular dynamics calculations support the experimental data. Furthermore, our novel gas-phase [2: 1] complexes are also found in 1,2-dichlorobenzene. Insights into the thermodynamic parameters of the binding process as well as the species distribution are derived from isothermal titration calorimetry (ITC) measurements. [ABSTRACT FROM AUTHOR]

Caryl–F bond activation has become an important and quickly developing method for construction of carbon-based materials. We report that alumina-mediated C–F bond activation (AmCFA) enables construction of PAHs with zigzag periphery. This method includes formal Csp3–H activation and opens an avenue for generation of carbon-based nanomagnets directly on technologically relevant surfaces. [ABSTRACT FROM AUTHOR]