DMP for Age distribuition Austria vs. Vienna

DMP from DMP online for the Data Stewardship project</p

Age distribution Austria vs. Vienna

The Figures produced from the Data Stewardship Project.</p

Age distribution Austria vs. Vienna DMP from RDMO

Age distribution Austria vs. Vienna DMP from RDMO, second DMP as comparison to the first.</p

Trinuclear Ruthenium Macrocycles: Toward Supramolecular Water Oxidation Catalysis in Pure Water

The incorporation of a Ru­(bda)­(bda = 2,2′-bipyridine-6,6′-dicarboxylate) water oxidation catalyst into a trinuclear metallosupramolecular macrocycle leads to increased stability and activity compared to the mononuclear reference system. To overcome solubility problems of such large structures in water and the need for large amounts of organic cosolvents, new macrocyclic water oxidation catalysts with improved water solubility become desirable. With triethylene glycol side chains, the required amount of acetonitrile as a cosolvent was halved, whereas the application of charged ammonium side chains allowed catalysis in pure water. The catalytic activity was found to be comparable to the parent compound. Kinetic experiments were performed to explain the rate differences between those new derivatives and showed that Coulombic repulsion between the charged side chains and Ce^IV leads to slower oxidation processes

C–Br Activation of Aryl Bromides at Ni⁰(NHC)₂: Stoichiometric Reactions, Catalytic Application in Suzuki–Miyaura Cross-Coupling, and Catalyst Degradation

Complex [Ni₂(^<i>i</i>Pr₂Im)₄(COD)] (<b>1</b>) (^<i>i</i>Pr₂Im = 1,3-diisopropylimidazolin-2-ylidene) is a very efficient catalyst for the Suzuki–Miyaura cross-coupling reaction of 4-bromotoluene with phenylboronic acid and also mediates the Ullmann-type homo-cross-coupling reaction of bromobenzene with a moderate efficiency. Stoichiometric reactions of complex <b>1</b> with aryl bromides (ArBr) at room temperature lead to mixtures of aryl bromo complexes of the type <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)­(Ar)] and the bis­(bromo) complex <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)₂] <b>2</b>. The complexes <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)­(Ar)] (for Ar = Ph <b>3</b>, 4-MeC₆H₄ <b>4</b>, 4-Me­(O)­CC₆H₄ <b>5</b>, 4-MeOC₆H₄ <b>6</b>, 4-MeSC₆H₄ <b>7</b>, 4-Me₂NC₆H₄ <b>8</b>, 2-C₅NH₄ <b>9</b>) can be selectively synthesized by working at low temperatures and using a high dilution of the starting materials. A major deactivation pathway for <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)­(Ar)] was identified in the presence of aryl bromides. This deactivation process includes (i) the formation of <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)₂] from <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)­(Ar)] (<b>2</b>) and ArBr and (ii) the formation of an imidazolium salt of the type 2­[^<i>i</i>Pr₂Im-Ar]⁺[NiBr₄]^2– from <i>trans</i>-[Ni­(^<i>i</i>Pr₂Im)₂(Br)₂] (<b>2</b>) and ArBr. The reactions of complex <b>2</b> with a series of aryl halides at higher temperatures lead to the decomposition of the bis­(carbene) nickel moiety with formation of the imidazolium salts 2­[ⁱPr₂Im-Ar]⁺[NiBr₂X₂]^2– (for X = I, Ar = Ph <b>10</b> and X = Br, Ar = Ph <b>11</b>, 4-MeC₆H₄ <b>12</b>, 4-FC₆H₄ <b>13</b>, 4-OSi­(CH₃)₃-C₆H₄ <b>14</b>) in high yields

To be or not to be – nematic liquid crystals from shape-persistent V-shaped nematogens with the ‘magic angle’

<p>The tetrahedral bending angle in V-shaped nematogens was claimed to be the optimum for finding a biaxial nematic liquid crystal phase. The benzo[1,2-b:4,3-b’]dithiophene core, recently successfully applied as a tetrahedral bending unit in mesogens with lateral flexible chains, is here embedded in a scaffold with only terminal chains, which conventionally promotes the formation of nematic phases at low temperature. A series of new mesogens has been successfully prepared, realising hockey-stick, hockey-stick dimer and V-shaped molecular topologies. Only the hockey-stick mesogens assemble in uniaxial nematic phases over a broad temperature range. Single crystal structure analysis of a hockey-stick and V-shaped compound reveal remarkable similarities with the benzodithiophene core wrapped by aliphatic chains. A model explaining the absence of nematic mesophases in the family of V-shaped, shape-persistent mesogens with terminal aliphatic chains is presented and results in the proposal of a new design for biaxial nematogens.</p

Novel Synthesis and Crystal Structure Analysis of <i>rac</i>-β-(Trimethylsilyl)alanine

A new efficient, convenient, and cost-saving multistep synthesis of rac-2-amino-3-(trimethylsilyl)propanoic acid (rac-β-(trimethylsilyl)alanine, rac-4) has been developed, starting from diethyl malonate (total yield 25%). In addition, rac-4 has been structurally characterized by single-crystal X-ray diffraction

Supplementary document for Spatiospectral Characterization of Ultrafast Pulse-Beams by Multiplexed Broadband Ptychography - 5444836.pdf

Supplemental Documen

Complete Monitoring of Coherent and Incoherent Spin Flip Domains in the Recombination of Charge-Separated States of Donor-Iridium Complex-Acceptor Triads

The spin chemistry of photoinduced charge-separated (CS) states of three triads comprising one or two triarylamine donors, a cyclometalated iridium complex sensitizer and a naphthalene diimide (NDI) acceptor, was investigated by transient absorption spectroscopy in the ns−μs time regime. Strong magnetic-field effects (MFE) were observed for two triads with a phenylene bridge between iridium complex sensitizer and NDI acceptor. For these triads, the lifetimes of the CS states increased from 0.6 μs at zero field to 40 μs at about 2 T. Substituting the phenylene by a biphenyl bridge causes the lifetime of the CS state at zero field to increase by more than 2 orders of magnitude (τ = 79 μs) and the MFE to disappear almost completely. The kinetic MFE was analyzed in the framework of a generalized Hayashi–Nagakura scheme describing coherent (S, T₀ ↔ T_±) as well as incoherent (S, T₀ ⇌ T_±) processes by a single rate constant <i>k</i>_±. The magnetic-field dependence of <i>k</i>_± of the triads with phenylene bridge spans 2 orders of magnitude and exhibits a biphasic behavior characterized by a superposition of two Lorentzians. This biphasic MFE is observed for the first time and is clearly attributable to the coherent (<i>B</i> < 10 mT) and incoherent (10 mT < <i>B</i> < 2 T) domains of spin motion induced by isotropic and anisotropic hyperfine coupling. The parameters of both domains are well understood in terms of the structural properties of the two triads, including the effect of electron hopping in the triad with two donor moieties. The kinetic model also accounts for the reduction of the MFE on reducing the rate constant of charge recombination in the triad with the biphenyl bridge

spatialChirpGif3.gif

Visualization 1 shows propagation of the central five spectral components of the spatially chirped pulse-beam from the prism experiment without the knife-edge. The top row shows the spatial profile of each beamlet as it propagates. The bottom left panel shows the summed intensity of these spectral components which is calculated from the individually propagated beamlets. The two bottom right panels show sagittal and tangential views of the beams colored by their local wavelengths, which are the same as Fig 3.a) and b). Here we are also showing the propagation of the beamlets, which are colored according to wavelength and have sizes proportional to their second moments. Based on these panels we can separately identify the beamlet crossing plane and focal plane of the beams in each direction