TY - JOUR A1 - Rudert, R. A1 - Schulz, Burkhard A1 - Reck, Günter A1 - Vollhardt, D. A1 - Kriwanek, J. T1 - (Carboxymethyl)dimethylundecylammonium bromide N2 - The title compound, C₁₅H₃₂NO₂⁺.Br⁻, crystallizes to form layers with interdigitating hydrocarbon chains stabilized by Br⁻۰۰۰H—O hydrogen bonds and Br⁻۰۰۰N⁺ contacts. KW - (Carboxymethyl)dimethylundecylammonium bromide KW - Crystal structure PY - 1995 DO - https://doi.org/10.1107/s0108270194011443 SN - 0108-2701 VL - 51 SP - 768 EP - 770 PB - Wiley-Blackwell CY - Oxford AN - OPUS4-56998 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Freyer, D. A1 - Reck, Günter A1 - Bremer, M. A1 - Voigt, W. T1 - Thermal behaviour and crystal structure of sodium-containing hemihydrates of calcium sulfate N2 - A metastable sodium-containing hemihydrate ((6-x)CaSO₄∙xNa₂SO₄∙3H₂O, 0≤x≤1) limited by the pentasalt composition Na₂SO₄∙5CaSO₄∙3H₂O occurs as an intermediate solid phase in the systems Na₂SO₄-CaSO₄-H₂O, NaCl-Na₂SO₄-CaSO₄-H₂O, and NaCl-CaSO₄-H₂O. X-Ray structure determination of a crystal with pentasalt composition results in a super-structure of the pure hemihydrate (CaSO₄∙0.5H₂O), in which one Ca²⁺ion is statistically replaced by two Na⁺ ions. One Na⁺ cation is situated in a Ca²⁺ position in only one of the three chains of CaSO₄ forming an axis of nearly three fold symmetry along the c-axis. The second Na⁺ is located in the water channel neighbouring to the first Na⁺. The hydrate crystallized in a monoclinic space group C121 (No. 5) with a=24.1781(11), b=13.805(2), c=12.7074(12) Å, β=90.089(12)°. The dehydration temperature of the hydrates depends on their Na⁺ ion content. A high Na⁺ content (in water channels) blocks the water escape strongly, and the dehydration temperature increases. Thermal behaviour is also effected by the crystal sizes. The thermograms of small crystals as opposed to large ones show a exothermic effect adjoining the endothermic dehydration. This may be indicative for a change in the dehydration mechanism upon crystal size. KW - Bassanite KW - Crystal structure KW - Sodium pentasalt KW - Calcium sulfate hemihydrate KW - Thermal analysis PY - 1999 DO - https://doi.org/10.1007/pl00010180 SN - 1434-4475 SN - 0026-9247 VL - 130 SP - 1179 EP - 1193 PB - Springer CY - Wien AN - OPUS4-61831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Vossmeyer, T. A1 - Reck, Günter A1 - Katsikas, L. A1 - Haupt, E. T. K. A1 - Schulz, Burkhard A1 - Weller, H. T1 - A "double-diamond superlattice" built up of Cd17S4(SCH2CH20H)26 clusters N2 - A simple preparation of Cd17S4(SCH2CH2OH)26 clusters in aqueous solution leads to the formation of colorless blocky crystals. X-ray structure determinations revealed a superlattice framework built up of covalently linked clusters. This superlattice is best described as two enlarged and interlaced diamond or zinc blende lattices. Because both the superlattice and the clusters display the same structural features, the crystal structure resembles the self-similarities known from fractal geometry. The optical spectrum of the cluster solution displays a sharp transition around 290 nanometers with a large Absorption coefficient (~84,000 per molar per centimeter). KW - superlattice KW - cluster KW - X-ray structure determination PY - 1995 DO - https://doi.org/10.1126/science.267.5203.1476 SN - 0036-8075 SN - 1095-9203 VL - 267 IS - 5203 SP - 1476 EP - 1479 PB - AAAS, American Association for the Advancement of Science CY - Washington, DC AN - OPUS4-44409 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reck, Günter A1 - Orgzall, I. A1 - Schulz, B. A1 - Dietzel, B. T1 - Two polymorphic forms of 2,5-bis(4-methoxycarbonylphenyl)-1,3,4-oxadiazole N2 - In the title compound, C13H14BN3O, the aziridine ring is an almost equilateral triangle, the C—C distance being slightly shorter than the C—N distances, probably because of the dative B—N bond. The five-membered ring, composed of two C atoms and N, B and O atoms, is fused with the aziridine ring to form a six-membered ring with a chair conformation. PY - 2003 DO - https://doi.org/10.1107/S0108270103022698 SN - 0108-2701 SN - 1600-5759 VL - 59 SP - o634 EP - o635 PB - Blackwell Publ. CY - Oxford AN - OPUS4-2694 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reck, Günter A1 - Becker, Roland T1 - Phenanthroline complexes of zinc and calcium carbamates N2 - Bis(N,N-di-n-butyl­di­thio­carbamato-?2S,S')(1,10-phenanthroline-?2N,N')­zinc(II) ethanol hemisolvate, [Zn(C9H18NS2)2(C12H8N2)]·0.5C2H6O, (I), and bis(N,N-di-n-hexyldithiocarbamato-?2S,S')­bis(1,10-phenanthroline-?2N,N')calcium(II), [Ca(C13H26NS2)2(C12H8N2)2], (II), are mixed-ligand com­plexes. In the first compound, the Zn atom has a distorted octahedral coordination, while in the second compound, the Ca atom is eight-coordinate, with four S and four N atoms forming a highly distorted cube. KW - X-ray structure analyses KW - Metal-organic complexes KW - Antioxidant properties PY - 2004 DO - https://doi.org/10.1107/S0108270104001441 SN - 0108-2701 SN - 1600-5759 VL - 60 SP - m134 EP - m136 PB - Blackwell Publ. CY - Oxford AN - OPUS4-3110 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kraus, Werner A1 - Stephan, H. A1 - Röllich, A. A1 - Matejka, Z. A1 - Reck, Günter T1 - K6H2[TiW11CoO40].13H2O, with a monotitanoundecatungstocobaltate(II) anion N2 - Hexapotassium dihydrogen monotitanoundeca­tungsto­cobalt­ate(II) trideca­hydrate, K6H2[TiW11CoO40]·13H2O, crystallizes from aqueous solution in the cubic space group P 3m. The structure was refined as an inversion twin. The [TiW11CoO40]8- anion has a Keggin structure with one W-atom site occupied by titanium and a central tetra­hedral CoO4 group. PY - 2005 DO - https://doi.org/10.1107/S1600536805005180 SN - 1600-5368 VL - 61 IS - 3 SP - i35 EP - i37 PB - Munksgaard CY - Copenhagen AN - OPUS4-7043 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Hennig, C. A1 - Reich, T. A1 - Kraus, Werner A1 - Reck, Günter A1 - Prokert, F. A1 - Schell, N. T1 - Combining EXAFS and X-ray powder diffraction to solve structures containing heavy atoms N2 - Determination of structures using x-ray powder diffraction is complicated if the reflection intensities are mainly influenced by the scattering from heavy atoms and the atomic coordinates of light atoms remain uncertain. A method like EXAFS, which is sensitive to short range order, gives reliable atomic distances in the surroundings of heavy atoms with a precision of ±0.02 Å. The probability for obtaining the complete structure from x-ray powder diffraction increases if one includes parameters derived from EXAFS measurements as restraints during the procedure of structure solving. We demonstrate the potential of combining EXAFS and x-ray powder diffraction by solving the structure UO2[H2AsO4]2H2O. The procedure starts with the determination of space group and cell parameters from XRD powder data. In a second step the absolute values of the structure factor |F| are separated by iterating a decomposition formula. The heavy atom positions are determined by direct methods. In the third step atomic distances of coordination polyhedra are estimated using EXAFS. Subsequently, the complete coordination geometries around the heavy atoms including reliable distances are used as restraints in the structure solving and refinement procedure. PY - 2005 DO - https://doi.org/10.1238/Physica.Topical.115a00352 SN - 0031-8949 SN - 1402-4896 SN - 0281-1847 VL - T115 SP - 352 EP - 355 PB - IoP Publ. CY - Bristol AN - OPUS4-7378 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reck, Günter T1 - Uric Acid Monohydrate a Nev Urinary Calculus Phase T2 - Tag der Chemie, Freie Universität Berlin CY - Berlin, Germany DA - 2005-06-08 PY - 2005 AN - OPUS4-7473 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reck, Günter T1 - X-ray Structure Determination from Powder Diffraction Data by PowderCell T2 - Tag der Chemie, Freie Universität Berlin CY - Berlin, Germany DA - 2005-06-08 PY - 2005 AN - OPUS4-7474 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schiller, E. A1 - Kraus, Werner A1 - Reck, Günter A1 - Spies, H. A1 - Pietzsch, H.-J. T1 - [2-Carboxy-2,2',2''-nitrilotris(ethanethiolato)-kappa4N,S,S',S''](triphenyl-phosphine-kappaP)rhenium(III) acetone solvate N2 - The title compound, [Re(C7H12NO2S3)(C18H15P)]·C3H6O, crystallizes from a solution in chloro­form–acetone–cyclo­­hexane with enantiomers disordered equally over each mol­ecular site. Hydrogen bonds between the carbox­yl groups form dimers in the crystal structure. PY - 2005 DO - https://doi.org/10.1107/S1600536805018660 SN - 1600-5368 VL - 61 IS - 7 SP - m1373 EP - m1375 PB - Munksgaard CY - Copenhagen AN - OPUS4-7613 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Schubert, G. A1 - Reck, Günter A1 - Jancke, Harald A1 - Kraus, Werner A1 - Patzelt, C. T1 - Uric acid monohydrate - a new urinary calculus phase N2 - In our laboratory more than 100,000 urinary calculi have been analysed since 1972. Amongst this huge sample, 15 specimens originating from a total of eight patients were observed showing similar characteristics but escaping unambiguous identification with any of the substances that have been described so far in urinary concrements. Therefore, the unknown substance was submitted to a more extended analytical regimen. Structural analysis by x-ray crystallography turned out to be most successful, identifying the unknown material as uric acid monohydrate. Uric acid monohydrate crystallizes in the monocline space group P21/c. Within the crystal, uric acid and water molecules form continuous layers by hydrogen bonds. This is in contrast to uric acid in its water free and its dihydrate forms, which both crystallize by forming 3-dimensional networks To the best of our knowledge , the existence of a monohydrate form of uric acid has not been reported so far. Accordingly, this is the first report on uric acid monohydrate as a urinary stone component. The frequency of only 0.015% in our survey indicates that uric acid monohydrate is rarely the main component in concrements, in contrast to uric acid and uric acid dihydrate with frequencies of 10% and 6%, respectively. The infrared spectrum of uric acid monohydrate is very similar to that of the other crystal forms of uric acid. Because of this similarity and its low frequency, uric acid monohydrate may have been overlooked as a component of urinary concrements. X-ray diffraction allows for better differentiation in routine stone analysis. All samples of uric acid monohydrate were found by solid state NMR spectroscopy to be highly contaminated by amorphous material. This material consisted of long aliphatic chains reminiscent of lipids and fatty acids, respectively. Concrements consisting of other forms of uric acid or urate lacked this amorphous component. Therefore, a role of this aliphatic material has to be taken into consideration when discussing the conditions that may favour the rare formation of concrements from uric acid monohydrate. As for as the metabolic situation of the affected patients is concerned, no common peculiarities became evident by a retrospective survey. KW - Uric acid monohydrate KW - Urinary calculus KW - Crystal structure KW - Solid state NMR KW - X-ray diffraction KW - Infrared spectroscopy PY - 2005 DO - https://doi.org/10.1007/s00240-005-0467-5 SN - 0300-5623 SN - 1434-0879 VL - 33 IS - 3 SP - 231 EP - 238 PB - Springer CY - Berlin AN - OPUS4-7676 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brehme, R. A1 - Gründemann, E. A1 - Schneider, M. A1 - Radeglia, Reiner A1 - Reck, Günter A1 - Schulz, Burkhard T1 - Aza-enamines X - Formylation of Pyrazole-4-carbaldehyde Hydrazones at the Hydrazonoazomethine C-Atom N2 - 1,3-Disubstituted 1H-pyrazole-4-carbaldehyde-N,N-di­methylhydrazones 1 reacted with the Vilsmeier-Haackreagent, corresponding to the aza-enamine concept, in an electrophilicsubstitution reaction at the azomethine C-atom yielding the 1,4,5-triaza-pentadieniumsalts 2. These were hydrolysed to give2-hydrazono-2-(1H-pyrazole-4-yl)ethanals 3. The electrophilic attack did not takeplace at the vinylogous position 5' of the pyrazoles. KW - Aza-enamines KW - Hydrazones KW - Heterocycles KW - Formylation KW - Alpha-oxoethanals PY - 2003 DO - https://doi.org/10.1055/s-2003-40527 SN - 0039-7881 SN - 1437-210X IS - 10 SP - 1615 EP - 1619 PB - Thieme [u.a.] CY - Stuttgart AN - OPUS4-2617 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Brehme, R. A1 - Reck, Günter A1 - Schulz, Burkhard A1 - Radeglia, Reiner T1 - Synthesis and Reactions of (1E,2Z)-2-N,N-Dialkylhydrazono-2-phenylethanal N,N-Dimethylhydrazones N2 - (1E,2Z)-2-N,N-Dialkylhydrazono-2-phenylethanal N,N-dimethylhydrazones 3a-e weresynthesised by the reaction of 1,4,5-triazapentadienium salts 2 with N,N-dimethylhydrazine. The compounds 3a and 3d didnot react with tosyl isocyanate in an electrophilic substitutionreaction at the azomethine C-1 as aza-enamines, but they reactedat room temperature in benzene in a 1,4-dipolar cycloaddition toyield 1,3,5-triazinan-2,4-diones 5a and 5d, whereas at 70 °Coctahydroimidazoimidazol-2,5-dione 6a wasformed via criss-cross addition reaction. With dimethyl sulfatein DMF, 3a was transformed into the trimethylhydrazoniumsalts 7a and 8a,isolated as co-crystallised perchlorates (molar ratio 1:1). KW - Aza-enamines KW - Heterocycles KW - Hydrazonium salts KW - 1,4-dipolar cycloaddition KW - Criss-cross addition reaction PY - 2003 DO - https://doi.org/10.1055/s-2003-40528 SN - 0039-7881 SN - 1437-210X IS - 10 SP - 1620 EP - 1625 PB - Thieme [u.a.] CY - Stuttgart AN - OPUS4-2618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reck, Günter A1 - Becker, Roland T1 - (N,N-Diiso­butyl­di­thio­carbamoyl­sulfinato)­zinc(II) N2 - Zinc di­alkyl di­thio­carbamoyl­sulfinates have been proposed as intermediates in the antioxidant action of the respective zinc di­alkyl di­thio­carbamate additives in hydro­carbon-based plastics and lubricants. As a model compound, zinc diiso­butyl di­thio­carbamoyl­sulfinate, [Zn(C9H18NO2S2)2], has been prepared and its crystal structure determined. PY - 2003 DO - https://doi.org/10.1107/S160053680301314X SN - 1600-5368 VL - 59 IS - 7 SP - m489 EP - m490 PB - Munksgaard CY - Copenhagen AN - OPUS4-2577 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Reck, Günter A1 - Orgzall, I. A1 - Schulz, B. T1 - 2,5-Di-p-tolyl-1,3,4-oxa­diazo­le N2 - The mol­ecule of the title compound, C16H14N2O, consists of two equivalent parts related by a twofold axis of the space group. The O atom occupies a special position on this twofold axis. PY - 2003 DO - https://doi.org/10.1107/S1600536803014867 SN - 1600-5368 VL - 59 IS - 8 SP - o1135 EP - o1136 PB - Munksgaard CY - Copenhagen AN - OPUS4-2609 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kraus, Werner A1 - Stephan, H. A1 - Reck, Günter T1 - Käfigstrukturen für den Einschluss von Pertechnetat und Perrhenat PY - 2004 SN - 0930-486X VL - 21 SP - 70 PB - Oldenbourg CY - München AN - OPUS4-3489 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Aree, T. A1 - Reck, Günter A1 - Schulz, Burkhard T1 - Crystal Structures of ß-Cyclodextrin Complexes with Formic Acid and Acetic Acid N2 - ß-Cyclodextrin (ߖCD)-formic acid (1) and ß-CD–acetic acid (2) inclusion complexes crystallizeas ß-CD...0.3HCOOH...7.7H2O and ß-CD...0.4CH3COOH...7.7H2O in themonoclinic space group P21 with comparable unit cell constants. Anisotropic refinement of atomic parameters against X-ray diffractiondata with Fo 2 > 2 (Fo 2) (986/8563 and 991/8358) converged at R-factors of 0.051 and 0.054 for 1 and 2,respectively. In both complexes, the ß-CD molecularconformation, hydration pattern and crystal packing are similar,but the inclusion geometries of the guest molecules are different.The ß-CD macrocycles adopt a ``round'' conformationstabilized by intramolecular, interglucose O3(n)...O2(n + 1)hydrogen bonds and their O6–H groups are systematically hydratedby water molecules. In the asymmetric unit, each complex contains one ß-CD, 0.3 formic acid (or 0.4 acetic acid), and 7.7 water moleculesthat are distributed over 9 positions. Water sites located in the ß-CD cavity hydrogen bond to the guest molecule. In thecrystal lattice, ß-CD molecules are packed in a typical ``herringbone'' fashion. In 1, the formic acid (occupancy 0.3) is entirely included in the ß-CD cavity such that its C atom is shifted from the O4-plane center to the ß-CD O6-side by 2.90 Å and C=O, C–-O bonds point to this side. In 2, the acetic acid (occupancy 0.4) is completely embedded in the ß-CD cavity, in which the carboxylic C atom is displaced from the O4-plane centerto the ß-CD O6-side by 0.87 Å; the C=O bond directsto the ß-CD O6-side and makes an angle of 15°to the ß-CD molecular axis. Furthermore, bothdimethyl-ß-CD-acetic acid and ß-CD-acetic acidcomplexes form a cage structure, showing that the small guestsenclosed entirely in the cavity either in ß-CD or indimethyl--CD do not affect the packing of the host macrocycles. KW - Acetic acid KW - Crystal structures KW - Beta-cyclodextrin KW - Formic acid KW - Hydrogen bond KW - Inclusion complex KW - X-ray analysis PY - 2003 DO - https://doi.org/10.1023/B:JIPH.0000003923.92981.0f SN - 1388-3127 SN - 0923-0750 SN - 1573-1111 VL - 47 IS - 1-2 SP - 39 EP - 45 PB - Kluwer Academics Publishers CY - Dordrecht AN - OPUS4-3707 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - GEN A1 - Stephan, H. A1 - Gloe, K. A1 - Kraus, Werner A1 - Spies, H. A1 - Johannsen, B. A1 - Wichmann, K. A1 - Reck, Günter A1 - Chand, D. K. A1 - Bharadwaj, P. K. A1 - Müller, U. A1 - Müller, W. M. A1 - Vögtle, F. ED - Moyer, B. A. T1 - Binding and extraction of pertechnetate and perrhenate by azacages T2 - Symposium Fundamentals and Applications of Anion Separations ; American Chemical Society national meeting CY - Chicago, IL, USA DA - 2001-08-25 PY - 2004 SN - 0-306-47911-7 SP - 151 EP - 168 PB - Kluwer Acad./Plenum Publ. CY - New York, NY AN - OPUS4-3667 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reck, Günter T1 - Growth and domain structure of PZN.PT crystals T2 - 2nd French-German Crystal Growth Meeting CY - Nancy, France DA - 2003-03-10 PY - 2003 AN - OPUS4-3752 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Reck, Günter T1 - Uric Acid Monohydrate - a New Urinary Calculus Phase T2 - Jahrestagung der Deutschen Gesellschaft für Kristallographie (DGK) CY - Berlin, Germany DA - 2003-03-10 PY - 2003 AN - OPUS4-4887 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Bertram, R. A1 - Reck, Günter A1 - Alex, V. A1 - Uecker, R. T1 - Growth and domain structure of PZN-PT crystals T2 - 2nd French-German Crystal Growth Meeting (FGCGM - 2003) CY - Nancy, France DA - 2003-03-10 PY - 2003 AN - OPUS4-2129 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -