TY - GEN A1 - Pabst, Falk A1 - Chang, Jen‐Hui A1 - Finzel, Kati A1 - Kohout, Miroslav A1 - Schmidt, Peer A1 - Ruck, Michael T1 - The Subbromide Bi5Br4 – On the Existence of a Hidden Phase T2 - Zeitschrift für Anorganische und Allgemeine Chemie N2 - Black and irregularly shaped crystals of the bismuth‐rich bromide Bi5Br4 were obtained as a by‐product of the reaction of CsBr, Bi, and BiBr3. X‐ray diffraction on a single‐crystal revealed its orthorhombic structure with the space group Pmmn (no. 59) and lattice parameters a = 1800.0(2) pm, b = 1476.1(1) pm, and c = 924.5(2) pm at 296 K. The structure is composed of Bi82+ and Bi95+ polycations and bromidobismuthate(III) anions according to the structured formula Bi5Br4 = Bi20Br16 = Bi82+Bi95+[BiBr5]2–[Bi2Br11]5–. Bi5Br4 is the bismuth‐richest among the bismuth subhalides containing isolated polycations. Extensive differential scanning calorimetry studies indicate that Bi5Br4 decomposes at 262 °C, i.e. one degree below the bismuth‐rich eutectic at 263 °C. All attempts towards a rational synthesis yielded predominantly the neighboring phases BiBr and Bi6Br7. KW - Bromine KW - Bismuth KW - Cluster KW - Phase Diagrams KW - Polycations KW - Crystal structure Y1 - 2020 UR - https://onlinelibrary.wiley.com/doi/10.1002/zaac.201800149 U6 - https://doi.org/10.1002/zaac.201800149 VL - 646 IS - 3 SP - 149 EP - 155 ER - TY - GEN A1 - Bähr, Martin A1 - Buhl, Johannes A1 - Radow, Georg A1 - Schmidt, Johannes A1 - Bambach, Markus A1 - Breuß, Michael A1 - Fügenschuh, Armin T1 - Stable honeycomb structures and temperature based trajectory optimization for wire-arc additive manufacturing T2 - Optimization and Engineering N2 - We consider two mathematical problems that are connected and occur in the layer-wise production process of a workpiece using wire-arc additive manufacturing. As the first task, we consider the automatic construction of a honeycomb structure, given the boundary of a shape of interest. In doing this, we employ Lloyd’s algorithm in two different realizations. For computing the incorporated Voronoi tesselation we consider the use of a Delaunay triangulation or alternatively, the eikonal equation. We compare and modify these approaches with the aim of combining their respective advantages. Then in the second task, to find an optimal tool path guaranteeing minimal production time and high quality of the workpiece, a mixed-integer linear programming problem is derived. The model takes thermal conduction and radiation during the process into account and aims to minimize temperature gradients inside the material. Its solvability for standard mixed-integer solvers is demonstrated on several test-instances. The results are compared with manufactured workpieces. KW - Mixed-integer linear programming KW - Geometric optimization KW - Eikonal equation KW - Heat transmission KW - Additive manufacturing KW - Centroidal Voronoi tesselation Y1 - 2021 U6 - https://doi.org/10.1007/s11081-020-09552-5 SN - 1573-2924 VL - 22 IS - 2 SP - 913 EP - 974 ER - TY - GEN A1 - Hanschmann, Henning A1 - Rödiger, Stefan A1 - Kramer, Toni A1 - Hanschmann, Katrin A1 - Steidle, Michael A1 - Fingerle, Volker A1 - Schmidt, Carsten A1 - Lehmann, Werner A1 - Schierack, Peter T1 - LoopTag FRET Probe System for Multiplex qPCR Detection of Borrelia Species T2 - Life Y1 - 2021 U6 - https://doi.org/10.3390/life11111163 SN - 2075-1729 VL - 11 IS - 11 ER - TY - GEN A1 - Ehrling, Sebastian A1 - Senkovska, Irena A1 - Efimova, Anastasia A1 - Bon, Volodymyr A1 - Abylgazina, Leila A1 - Petkov, Petko A1 - Evans, Jack D. A1 - Attallah, Ahmed Gamal A1 - Wharmby, Michael Thomas A1 - Roslova, Maria A1 - Huang, Zhehao A1 - Tanaka, Hideki A1 - Wagner, Andreas A1 - Schmidt, Peer A1 - Kaskel, Stefan T1 - Temperature Driven Transformation of the Flexible Metal-Organic Framework DUT-8(Ni) T2 - Chemistry - a European journal N2 - DUT-8(Ni) metal-organic framework belongs to the family of flexible pillared layer materials. The desolvated framework can be obtained in the open pore form (op) or in the closed pore form (cp), depending on the crystal size regime. In the present work, we report on the behaviour of desolvated DUT-8(Ni) at elevated temperatures. For both, op and cp variants, heating causes a structural transition, leading to an new, crystalline compound, containing two interpenetrated networks. The state of the framework before transition (op vs. cp) influences the transition temperature: the small particles of the op phase transform at significantly lower temperature in comparison to the macroparticles of the cp phase, transforming close to the decomposition temperature. The new compound, confined closed pore phase (ccp), was characterized by powder X-ray diffraction and spectroscopic techniques, such as IR, EXAFS, and positron annihilation lifetime spectroscopy (PALS). Thermal effects of structural cp to ccp transitions were studied using differential scanning calorimetry (DSC), showing an overall exothermic effect of the process, involving bond breaking and reformation. Theoretical calculations reveal the energetics, driving the observed temperature induced phase transition. KW - Metal organic framework (MOF) KW - Thermal analysis KW - Crystal structure KW - Phase transition Y1 - 2022 UR - https://chemistry-europe.onlinelibrary.wiley.com/doi/10.1002/chem.202201281 U6 - https://doi.org/10.1002/chem.202201281 SN - 1521-3765 VL - 28 IS - 55 SP - 1 EP - 10 ER - TY - GEN A1 - Matthies, Ellen A1 - Beer, Katrin A1 - Böcher, Michael A1 - Sundmacher, Kai A1 - König-Mattern, Laura A1 - Arlinghaus, Julia A1 - Blöbaum, Anke A1 - Jaeger-Erben, Melanie A1 - Schmidt, Karolin T1 - Framework conditions for the transformation toward a sustainable carbon-based chemical industry – A critical review of existing and potential contributions from the social sciences T2 - Journal of Cleaner Production Y1 - 2024 U6 - https://doi.org/10.1016/j.jclepro.2024.143279 SN - 0959-6526 VL - 470 (2024) SP - 1 EP - 13 PB - Elsevier BV ER - TY - GEN A1 - Tschammer, Rudi A1 - Buß, Lars A1 - Pożarowska, Emilia A1 - Morales, Carlos A1 - Senanayake, Sanjaya D. A1 - Prieto, Mauricio J. A1 - Tănase, Liviu C. A1 - de Souza Caldas, Lucas A1 - Tiwari, Aarti A1 - Schmidt, Thomas A1 - Niño, Miguel A. A1 - Foerster, Michael A1 - Falta, Jens A1 - Flege, Jan Ingo T1 - High-temperature growth of CeOx on Au(111) and behavior under reducing and oxidizing conditions T2 - The journal of physical chemistry C N2 - Inverse oxide–metal model catalysts can show superior activity and selectivity compared with the traditional supported metal–oxide architecture, commonly attributed to the synergistic overlayer–support interaction. We have investigated the growth and redox properties of ceria nanoislands grown on Au(111) between 700 and 890 °C, which yields the CeO2–Au(111) model catalyst system. We have observed a distinct correlation between deposition temperature, structural order, and oxide composition through low-energy electron microscopy, low-energy electron diffraction, intensity–voltage curves, and X-ray absorption spectroscopy. Improved structural order and thermal stability of the oxide have been achieved by increasing the oxygen chemical potential at the substrate surface using reactive oxygen (O/O2) instead of molecular O2 during growth. In situ characterization under reducing (H2) and oxidizing atmospheres (O2, CO2) indicates an irreversible loss of structural order and redox activity at high reduction temperatures, while moderate temperatures result in partial decomposition of the ceria nanoislands (Ce3+/Ce4+) to metallic cerium (Ce0). The weak interaction between Au(111) and CeOx would facilitate its reduction to the Ce0 metallic state, especially considering the comparatively strong interaction between Ce0 and Au0. Besides, the higher reactivity of atomic oxygen promotes a stronger interaction between the gold and oxide islands during the nucleation process, explaining the improved stability. Thus, we propose that by driving the nucleation and growth of the ceria/Au system in a highly oxidizing regime, novel chemical properties can be obtained. KW - Inverse oxide-metal model catalysts KW - Ceria nanoislands KW - Growth KW - Redox properties KW - Low-energy electron microscopy (LEEM) KW - Low-energy electron diffraction (LEED) KW - Intensity–voltage curves KW - X-ray absorption spectroscopy (XAS) Y1 - 2025 U6 - https://doi.org/10.1021/acs.jpcc.4c08072 SN - 1932-7447 VL - 129 IS - 7 SP - 3583 EP - 3594 PB - American Chemical Society (ACS) CY - Washington, DC ER - TY - GEN A1 - Veldkamp, Edzo A1 - Schmidt, Marcus A1 - Markwitz, Christian A1 - Beule, Lukas A1 - Beuschel, René A1 - Biertümpfel, Andrea A1 - Bischel, Xenia A1 - Duan, Xiaohong A1 - Gerjets, Rowena A1 - Göbel, Leonie A1 - Graß, Rüdiger A1 - Guerra, Victor A1 - Heinlein, Florian A1 - Komainda, Martin A1 - Langhof, Maren A1 - Luo, Jie A1 - Potthoff, Martin A1 - Ramshorst, Justus G. V. van A1 - Rudolf, Carolin A1 - Seserman, Diana-Maria A1 - Shao, Guodong A1 - Siebicke, Lukas A1 - Svoboda, Nikolai A1 - Swieter, Anita A1 - Carminati, Andrea A1 - Freese, Dirk A1 - Graf, Torsten A1 - Greef, Jörg M. A1 - Isselstein, Johannes A1 - Jansen, Martin A1 - Karlovsky, Petr A1 - Knohl, Alexander A1 - Lamersdorf, Norbert A1 - Priesack, Eckart A1 - Wachendorf, Christine A1 - Wachendorf, Michael A1 - Corre, Marife D. T1 - Multifunctionality of temperate alley-cropping agroforestry outperforms open cropland and grassland T2 - Communications Earth & Environment N2 - AbstractIntensively managed open croplands are highly productive but often have deleterious environmental impacts. Temperate agroforestry potentially improves ecosystem functions, although comprehensive analysis is lacking. Here, we measured primary data on 47 indicators of seven ecosystem functions in croplands and 16 indicators of four ecosystem functions in grasslands to assess how alley-cropping agroforestry performs compared to open cropland and grassland. Carbon sequestration, habitat for soil biological activity, and wind erosion resistance improved for cropland agroforestry (P ≤ 0.03) whereas only carbon sequestration improved for grassland agroforestry (P < 0.01). In cropland agroforestry, soil nutrient cycling, soil greenhouse gas abatement, and water regulation did not improve, due to customary high fertilization rates. Alley-cropping agroforestry increased multifunctionality, compared to open croplands. To ameliorate the environmental benefits of agroforestry, more efficient use of nutrients is required. Financial incentives should focus on conversion of open croplands to alley-cropping agroforestry and incorporate fertilizer management. Y1 - 2023 U6 - https://doi.org/10.1038/s43247-023-00680-1 SN - 2662-4435 VL - 4 IS - 1 PB - Springer Science and Business Media LLC ER - TY - GEN A1 - Lucke, Bernhard A1 - Schmidt, Michael A1 - Al-Saad, Ziad A1 - Hüttl, Reinhard F. A1 - Bens, Oliver T1 - The abandonment of the Decapolis region in Northern Jordan - forced by environmental change? T2 - Quaternary International Y1 - 2005 SN - 1040-6182 VL - 135 IS - 1 SP - 65 EP - 81 ER - TY - GEN A1 - Balas, Johannes A1 - Urbank, Christian A1 - Kaden, Peter A1 - Patzschke, Michael A1 - März, Juliane A1 - Kvashnina, Kristina O. A1 - Schmidt, Moritz A1 - Stumpf, Thorsten A1 - Gericke, Robert T1 - Bonding trends in pyridine-2-thiolato complexes of tetravalent actinides T2 - Inorganic chemistry N2 - Complexes of tetravalent actinides (An: Th, U, Np, Pu) with the bidentate (N,S)-donor ligand pyridine-2-thiolate (2-PyS, PyS−) were synthesized in 1:4 or 1:5 ratios. This includes the first structurally characterized Np complex with (N,S)-donor ligands, filling a notable gap in An coordination chemistry. An improved synthetic approach with PyS–SiMe3 enabled efficient formation of the 1:4 complexes in THF as coordinating solvent. The compounds were comprehensively characterized in solution and in solid phase, supported by quantum chemical calculations. Experimental and theoretical results show matching trends in the binding behavior of AnIV. The covalent bond contributions in An–N and An–S bonding increase along the series of An from Th to Pu. The bonds to the soft sulfur donors consistently have the highest covalent contributions with a remarkably high percentage for Pu–S (IQA analysis: >34%) over the harder N donors or An–O bonds of coordinating THF. High-resolution X-ray absorption and infrared spectroscopy indicate similar electronic and structural properties across AnIV complexes, while SQUID magnetometry uncovered significant differences in magnetic behavior at low temperatures depending on the complex compositions. This work advances the understanding of An-ligand bonding, emphasizing covalency and electronic structures, and expands fundamental insights into An chemistry. KW - Actinides KW - Single-crystal X-ray diffraction KW - Bonding trends KW - HERFD-XANES KW - SQUID Y1 - 2025 U6 - https://doi.org/10.1021/acs.inorgchem.5c03369 SN - 1520-510X VL - 64 IS - 44 SP - 21919 EP - 21931 PB - American Chemical Society CY - Washington, DC ER - TY - GEN A1 - Bölte, Jens-Henning A1 - Utgenannt, Stephan A1 - Schmidt, Max A1 - Klepel, Olaf A1 - Bron, Michael A1 - Rokicińska, Anna A1 - Jarczewski, Sebastian A1 - Kuśtrowski, Piotr T1 - S-doped and N+S-co-doped carbon catalysts in redox reactions T2 - Microporous and mesoporous materials N2 - In this contribution, the effects of heteroatom doping of porous carbon materials with S and N on their ability to catalyze redox-reactions involving the activation of molecular oxygen were investigated. For this purpose, a library of in total 54 undoped, S-doped and N + S-co-doped porous carbons was obtained via a template-based synthesis procedure using mesoporous silica gel as the template. To understand the influence of S on the properties of the doped carbons three different S-containing precursors, namely dimethyl sulfoxide (DMSO), p-toluene sulfonic acid and thiophene, were used. In order to investigate possible synergistic effects of S- and N-co-doping, urea was employed as the sole N-containing precursor. The obtained carbon catalysts were characterized by selected methods such as N2-physisorption at 77 K, X-ray diffraction (XRD), Raman spectroscopy, elemental analysis and X-ray photoelectron spectroscopy (XPS). Each carbon catalyst was tested in the oxidation of sulfurous acid (OSA) to sulfuric acid, the electrochemical oxygen reduction (ORR) and the oxidative dehydrogenation (ODH) of ethylbenzene. Owing to the similar textural and structural properties achieved through template-based synthesis of the carbon catalyst library, the results of the catalytic redox-reactions could directly be related to the respective heteroatom dopant. The observed trends indicate that in these redox-reactions S-species behave somewhat similar to O-species bound on the carbon surface. Furthermore, it can be shown that N + S co-doping rather combines the positive and negative effects of the individual dopants on the activity, than creating a synergistic effect that surpasses the individual contribution. KW - Porous carbon KW - Heteroatom-doping KW - Redox-reactions KW - Catalysis KW - Oxidation of sulfurous acid KW - Oxygen reduction reaction KW - Oxidative dehydrogenation of ethylbenzene Y1 - 2026 U6 - https://doi.org/10.1016/j.micromeso.2026.114129 SN - 1873-3093 VL - 407 SP - 1 EP - 11 PB - Elsevier BV CY - Amsterdam ER -