TY - JOUR A1 - Pawlik, Alf A1 - König, R. A1 - Scholz, G. A1 - Kemnitz, E. A1 - Brunklaus, G. A1 - Bertmer, M. A1 - Jäger, Christian T1 - Access to local structures of HS-AIF3 and its precursor determined by high-resolution solid-state NMR KW - Aluminium fluoride KW - 27Al NMR KW - MQMAS KW - Amorphous materials KW - Catalysts PY - 2009 DO - https://doi.org/10.1021/jp904626k SN - 1932-7447 SN - 1089-5639 VL - 113 IS - 38 SP - 16674 EP - 16680 PB - Soc. CY - Washington, DC AN - OPUS4-20463 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zänker, Steffen A1 - Scholz, G. A1 - Heise, M. A1 - Kemnitz, E. A1 - Emmerling, Franziska T1 - New 2D layered structures with direct fluorine-metal bonds: MF(CH3COO) (M: Sr, Ba, Pb) N2 - New coordination polymers with 2D network structures with fluorine directly coordinated to the metal ion were prepared both via mechanochemical synthesis and fluorolytic sol–gel synthesis. Depending on the synthesis route, the samples show different particle sizes, according to SEM imaging. The crystal structures of barium acetate fluoride, strontium acetate fluoride, and lead acetate fluoride (BaFIJCH3COO), SrFIJCH3COO) and PbFIJCH3COO)) were solved from X-ray powder diffraction data. The structure solution is backed by the results from 19F MAS NMR, FT IR data, and thermal analysis. The calculated chemical shifts of the 19F MAS NMR spectra coincide well with the measured ones. It turns out that the grinding conditions have a remarkable influence on the mechanochemical synthesis and its products. Our systematic study also indicates a strong influence of the atomic radii of Ca, Sr, Ba, and Pb on the success of the syntheses. KW - Mechanochemistry KW - Coordination polymers PY - 2020 DO - https://doi.org/10.1039/d0ce00287a VL - 22 IS - 16 SP - 2772 EP - 2780 PB - Royal Society of Chemistry AN - OPUS4-50789 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Al-Terkawi, Abdal-Azim A1 - Scholz, G. A1 - Emmerling, Franziska A1 - Kemnitz, E. T1 - Mechanochemical synthesis, characterization, and structure determination of new alkaline earth metal-tetrafluoroterephthalate frameworks: Ca(pBDC‑F4 )·4H2O, Sr(pBDC‑F4 )·4H2O, and Ba(pBDC‑F4 ) N2 - New fluorinated alkaline earth metal−organic frameworks were successfully synthesized by milling of metal hydroxides M(OH)2 with tetrafluoroterephthalic acid H2 pBDC-F4. Both calcium- and strontium-tetrafluoroterephthalates are tetrahydrated, while the barium tetrafluoroterephthalate is free of coordinating water molecules. The two isomorphic structures Ca(pBDC-F4)·4H2O and Sr(pBDC-F4)·4H2O were solved from the powder diffraction data by ab initio structure determination and subsequent Rietveld refinement. The products were thoroughly characterized by elemental analysis, thermal analysis, magicangle spinning NMR, Fourier transform infrared spectroscopy, scanning electron microscopy imaging, and Brunauer−Emmett−Teller measurements. Our findings suggest that the mechanochemical synthesis route is a promising approach for the preparation of new fluorinated alkaline earth metal−organic frameworks. KW - Mechanochemistry KW - MOFs KW - XRD PY - 2016 UR - http://pubs.acs.org/doi/abs/10.1021/acs.cgd.5b01457 DO - https://doi.org/10.1021/acs.cgd.5b01457 SN - 1528-7483 VL - 16/4 SP - 1923 EP - 1933 PB - American Chemical Society CY - Washington, DC, USA AN - OPUS4-35940 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Zänker, Steffen A1 - Scholz, G. A1 - Xu, W. A1 - Kemnitz, E. A1 - Emmerling, Franziska T1 - Structure and properties of fluorinated and non-fluorinated Ba-coordination polymers - the position of fluorine makes the difference N2 - As the most electronegative element, fluorine has a strong influence on material properties such as absorption behaviour or chemical and thermal stability. Fluorine can be easily integrated into coordination polymers (CPs) via a fluorinated acetate, here trifluoroacetate in Ba(CF3COO)2, or directly via a metal fluorine bond (BaF(CH3COO)). In the present study both possibilities of fluorine integration were tested and their effect on structure and properties of barium coordination polymers was investigated in comparison with the non-fluorinated barium acetate (Ba(CH3COO)2). In addition to the study of their thermal behaviour and their decomposition temperature, the CPs structures were tested for their application as possible anode materials in lithium ion batteries and for their sorption of water and ammonia. The properties of the CPs can be traced back to the individual structural motifs and could thus trigger new design ideas for CPs in LIBs and/or catalysis. KW - Alkaline earth metal coordination polymers KW - Lithium-ion battery KW - Water stability KW - Fluorine coordination PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-524041 DO - https://doi.org/10.1002/zaac.202000360 SN - 0044-2313 VL - 647 IS - 9 SP - 1014 EP - 1024 PB - Wiley-VCH GmbH AN - OPUS4-52404 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Al-Terkawi, Abdal-Azim A1 - Scholz, G. A1 - Emmerling, Franziska A1 - Kemnitz, E. T1 - Strontium-coordination polymers based on tetrafluorophthalic and phthalic acids: mechanochemical synthesis, ab initio structures determination, and spectroscopic characterization N2 - Two strontium-based dicarboxylate systems [Sr(oBDC-F4)(H2O)2] (1) and [{Sr(oBDC)(H2O)2)·H2O] (2) were synthesized mechanochemically via milling of Sr(OH)2·8H2O with tetrafluorophthalic acid (H2oBDC-F4) or phthalic acid (H2oBDC), respectively. The new structures were determined ab initio from the powder X-ray diffraction (PXRD) data. Both compounds 1 and 2 crystallize in the monoclinic space group P21 /c as two-dimensional coordination polymers (2D-CPs). The determined structures were validated by extended X-ray absorption (EXAFS) data. Compounds 1 and 2 show different thermal stabilities. The fluorinated CP 1 is decomposed at 300 °C while the nonfluorinated CP 2 transforms into a new phase after thermal treatment at 400 °C. The two hydrated CPs exhibit small surface areas which increase after the thermal posttreatment for 1 but remains unchanged for the dehydrated sample of 2. Dynamic vapor sorption (DVS) experiments indicate that both the dehydrated and hydrated samples of 2 depict no significant differences in their adsorption isotherms. The DVS of water indicates that the phase transition after thermal posttreatment of 2 is irreversible. KW - Mechanochemistry KW - XRD KW - NMR PY - 2017 DO - https://doi.org/10.1039/c7dt02564e SN - 1477-9226 SN - 1477-9234 VL - 46 IS - 37 SP - 12574 EP - 12587 PB - The Royal Society of Chemistry CY - Cambridge AN - OPUS4-42261 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Breitfeld, Steffen A1 - Scholz, G. A1 - Emmerling, Franziska A1 - Kemnitz, E. T1 - BaF-benzenedicarboxylate: the first mechanochemical N2 - Anewbariumcoordination polymer, BaF-benzenedicarboxylate (BaF(p-BDC)0.5), with fluorine directly coordinated to the metal cation, was prepared by mechanochemical synthesis routes. Phase-pure BaF-benzenedicarboxylate was synthesized by milling starting either from barium hydroxide or from Barium acetate as sources for barium cations. In both cases, the second reactant was 1,4-benzenedicarboxylic acid (H2(p-BDC)). Ammonium fluoride was used as fluorinating agent directly at milling. This is the first mechanochemical synthesis of coordination polymers where fluorine is directly coordinated to the metal cation. Following the second possibility, barium acetate fluoride (Ba(OAc)F) is formed as ntermediate product after milling, and the new coordination polymer is accessible only after washing with water and dimethyl sulfoxide. The new compound BaF(p-BDC)0.5 was characterized by X-ray powder diffraction, FTIR-, and 19F, 1H-13C CP MAS NMR spectroscopies, DTA-TG, and elemental Analysis. KW - Milling KW - MOF PY - 2018 DO - https://doi.org/10.1007/s10853-018-2331-3 SN - 0022-2461 VL - 53 IS - 19 SP - 13682 EP - 13689 PB - Springer AN - OPUS4-45677 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Meißner, G. A1 - Dirican, D. A1 - Jäger, Christian A1 - Braun, T. A1 - Kemnitz, E. T1 - Et3GeH versus Et3SiH: controlling reaction pathways in catalytic C–F bond activations at a nanoscopic aluminum chlorofluoride† N2 - Catalytic C–F bond activation reactions of mono- and polyfluoroalkanes at Lewis acidic amorphous aluminum chlorofluoride (ACF) are presented. The hydrogen sources Et3GeH or Et3SiH control the selectivity of the conversions. The immobilization of Et3GeH at ACF resulted in catalytic dehydrohalogenation reactions to yield olefins under very mild conditions. In contrast, if Et3SiH is immobilized at ACF, C–C coupling occured and the formation of Friedel–Crafts products was observed. MAS NMR spectroscopic studies revealed information about the surface binding of the substrates. KW - Vapor-phase hydrofluorination KW - Carbon-fluorine bonds KW - Vinyl fluoride KW - Phosphine-ligands KW - Room-temperature KW - Building-blocks KW - Etal-complexes KW - Germylium ions KW - Lewis-acids KW - Hydrodefluorination PY - 2017 DO - https://doi.org/10.1039/c7cy00845g SN - 2044-4753 SN - 2044-4761 VL - 7 IS - 15 SP - 3348 EP - 3354 PB - The Royal Society of Chemistry AN - OPUS4-41836 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - König, R. A1 - Scholz, G. A1 - Kemnitz, E. T1 - Crystalline aluminium hydroxy fluorides: Structural insights obtained by high field solid state NMR and 27Al chemical shift trend analysis T2 - Gesellschaft Deutscher Chemiker CY - Regensburg, Germany DA - 2008-09-22 PY - 2008 AN - OPUS4-17956 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - König, R. A1 - Scholz, G. A1 - Kemnitz, E. T1 - Crystalline aluminium hydroxyl fluorides: Structural insights obtained by high-field solid state NMR and 27Al chemical shift trend analysis T2 - Gesellschaft Deutscher Chemiker CY - Regensburg, Germany DA - 2008-09-22 PY - 2008 AN - OPUS4-17957 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - König, R. A1 - Scholz, G. A1 - Scheurell, K. A1 - Heidemann, D. A1 - Buchem, I. A1 - Unger, Wolfgang A1 - Kemnitz, E. T1 - Spectroscopic characterization of crystalline AIF3 phases N2 - A comprehensive spectroscopic characterization of all known crystalline AlF3 phases (α-, β-, η-, κ-, θ-AlF3) is presented for the first time in this study. Beside their X-ray diffraction powder patterns, which were already published in the literature, 27Al and 19F MAS NMR, FT IR and XPS spectroscopic techniques were applied for all phases in a consistent manner. For all phases prepared the utilization of 27Al satellite transition (SATRAS) NMR allowed to determine the quadrupolar parameters of the aluminium sites including their distributions. In addition, η-AlF3 was isolated with high phase purity and characterized following a new preparation path different from those known so far in the literature. KW - Crystalline aluminium fluorides KW - Solid state NMR KW - FT IR KW - XPS PY - 2010 DO - https://doi.org/10.1016/j.jfluchem.2009.10.015 SN - 0022-1139 SN - 1873-3328 VL - 131 IS - 1 SP - 91 EP - 97 PB - Elsevier CY - Amsterdam AN - OPUS4-20991 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -