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Bas van Genabeek Brigitte A. G. Lamers Craig J. Hawker E. W. Meijer Will R. Gutekunst Bernhard V. K. J. Schmidt 《Journal of polymer science. Part A, Polymer chemistry》2021,59(5):373-403
Precise oligomeric materials constitute a growing area of research with implications for various applications as well as fundamental studies. Notably, this field of science which can be termed macro-organic chemistry, draws inspiration from both traditional polymer chemistry and organic synthesis, combining the molecular precision of organic chemistry with the materials properties of macromolecules. Discrete oligomers enable access to unprecedented materials properties, for example, in self-assembled structures, crystallization, or optical properties. The degree of control over oligomer structures resembles many biological systems and enables the design of materials with tailored properties and the development of fundamental structure–property relationships. This Review highlights recent developments in macro-organic chemistry from synthetic concepts to materials properties, with a focus on self-assembly and molecular recognition. Finally, an outlook for future research directions is provided. 相似文献
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Mathias Mallmann Sebastian Wendl Dr. Philipp Strobel Dr. Peter J. Schmidt Prof. Dr. Wolfgang Schnick 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(28):6257-6263
Nitridophosphates exhibit an intriguing structural diversity with different structural motifs, for example, chains, layers or frameworks. In this contribution the novel nitridophosphate Sr3P3N7 with unprecedented dreier double chains is presented. Crystalline powders were synthesized using the ammonothermal method, while single crystals were obtained by a high-pressure multianvil technique. The crystal structure of Sr3P3N7 was solved and refined from single-crystal X-ray diffraction and confirmed by powder X-ray methods. Sr3P3N7 crystallizes in monoclinic space group P2/c. Energy-dispersive X-ray and Fourier-transformed infrared spectroscopy were conducted to confirm the chemical composition, as well as the absence of NHx functionality. The optical band gap was estimated to be 4.4 eV using diffuse reflectance UV/Vis spectroscopy. Upon doping with Eu2+, Sr3P3N7 shows a broad deep-red to infrared emission (λem=681 nm, fwhm≈3402 cm−1) with an internal quantum efficiency of 42 %. 相似文献
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Poly[N‐(10‐oxo‐2‐vinylanthracen‐9(10H)‐ylidene)cyanamide] as a novel cathode material for li‐organic batteries 下载免费PDF全文
Daniel Schmidt Bernhard Häupler Christian Stolze Martin D. Hager Ulrich S. Schubert 《Journal of polymer science. Part A, Polymer chemistry》2015,53(21):2517-2523
Redox‐active polymers draw significant attention as active material in secondary batteries during the last decade. A new anthraquinone‐based redox‐active monomer was designed, which electrochemical behavior was tailored by mono‐modification of one keto group. The monomer exhibits two one‐electron redox reactions and has a low molar mass, resulting in a high theoretical capacity of 207 mAh/g. The polymerization of the monomer was optimized by variation of solvent and initiator. Moreover, the electrochemical behavior was studied using cyclic voltammetry and the polymer was used as active material in a composite electrode in lithium organic batteries. The polymer reveals a cell potential of 2.3 V and a promising capacity of 137 mAh/g. During the first 100 cycles, the capacity drops to 85% of the initial value. The influence of the charging speed on the charging/discharging properties of the batteries was further investigated. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2015 , 53, 2517–2523 相似文献
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Dipl.‐Chem. Andreas Kraft B. Sc. Patrick Roth Dr. David Schmidt M. Sc. Johannes Stangl Prof. Dr. Klaus Müller‐Buschbaum Dr. Florian Beuerle 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(17):5982-5987
Hexakis‐substituted [60]fullerene adducts with icosahedral symmetry provide an unprecedented scaffold for the spatial arrangement of twelve functional groups with high geometric precision. This unique molecular symmetry identifies such polyfunctional organic building blocks as potential highly connective linkers for coordination polymer and metal–organic framework synthesis. Hereby, the linker exhibits a higher connectivity than the metal ions and with the main connectivity based on the ligand, this can create a new type of inversely cross‐linked framework. Two hexakis adducts bearing either twelve glycolic acid or 3‐hydroxypropionic acid side chains attached to its malonate units were incorporated as organic connectivity centers in the first fullerene‐containing three‐dimensional frameworks by coordination with Zn2+. 相似文献
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Reflections from geometric discontinuities can be used with ultrasonic energy to predict the temperature of an interface where classical temperature measurement techniques are impractical because of physical access limitations or harsh environmental conditions. Additionally, these same ultrasonic measurements can be used with inversion methods commonly applied to ill-posed heat transfer problems to increase the accuracy of the measurement of surface temperature or heat flux at the surface of interest. Both methods for determining surface temperature are presented, along with a comparison of results both from a verification example and using data gathered in a field test of the methods. The results obtained with these two methods are shown to be in good agreement with an empirical relationship used in the design of large caliber guns. 相似文献
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Jorge Segovia Chen Chen Ian C. Cloët Craig D. Roberts Sebastian M. Schmidt Shaolong Wan 《Few-Body Systems》2014,55(1):1-33
Predictions obtained with a confining, symmetry-preserving treatment of a vector ? vector contact interaction at leading-order in a widely used truncation of QCD’s Dyson–Schwinger equations are presented for Δ and Ω baryon elastic form factors and the γN → Δ transition form factors. This simple framework produces results that are practically indistinguishable from the best otherwise available, an outcome which highlights that the key to describing many features of baryons and unifying them with the properties of mesons is a veracious expression of dynamical chiral symmetry breaking in the hadron bound-state problem. The following specific results are of particular interest. The Δ elastic form factors are very sensitive to m Δ. Hence, given that the parameters which define extant simulations of lattice-regularised QCD produce Δ-resonance masses that are very large, the form factors obtained therewith are a poor guide to properties of the Δ(1232). Considering the Δ-baryon’s quadrupole moment, whilst all computations produce a negative value, the conflict between theoretical predictions entails that it is currently impossible to reach a sound conclusion on the nature of the Δ-baryon’s deformation in the infinite momentum frame. Results for analogous properties of the Ω baryon are less contentious. In connection with the N → Δ transition, the Ash-convention magnetic transition form factor falls faster than the neutron’s magnetic form factor and nonzero values for the associated quadrupole ratios reveal the impact of quark orbital angular momentum within the nucleon and Δ; and, furthermore, these quadrupole ratios do slowly approach their anticipated asymptotic limits. 相似文献
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Dr. Martin Schmidt Prof. Albert Masson Prof. Hai‐Ping Cheng Prof. Catherine Bréchignac 《Chemphyschem》2015,16(4):855-865
Adsorption and coadsorption studies on free silver clusters show that nitrogen physisorbs like rare gases, whereas oxygen chemisorbs with similarities and differences to bulk silver surfaces. Silver nanoparticles activate, or even dissociate adsorbed oxygen molecules. The global electron configurations of the adsorbent and adsorbate dominate the stability at small clusters. This is more important than geometry and site effects. Due to electronic shell effects and electron pairing, the activation of oxygen strongly varies with size. At more than 40 free electrons in the complex, such quantum effects start to blur. The size dependence becomes smoother and general trends govern the reactivity, which is driven by the interaction between the charge state of the nanoparticle and the charge transfer of the reaction. 相似文献