| 21 | Author
| H. Arald Hillebrecht, G.Erhard Thiele, Alrik Koppenhöfer, Heinrich Vahrenkamp | Requires cookie* | | Title
| Kristallstruktur und Schwingungsspektren von Zn(NH 3)4(C104)2 Crystal Structure and Vibrational Spectra of Zn(N H 3)4(C104)2  | | | Abstract
| The title compound Z n (N H 3)4(C104)2 crystallizes in the space group F 43m with a = 10.240(1) A. The crystal structure consists of tetrahedral Z n (N H 3)4 cations and two non equivalent C 104 anions with crystallographic Td symmetry. The complex ions constitute an arrangement which is known from the Zintl phase M gAgAs. The Z n(N H 3)4 cations are ccp packed with perchlorate anions in octahedral and tetrahedral voids. W hereas the C 104 ions centered at tetrahedral holes do not interact with the other lattice components, the perchlo rate ions in the octahedral voids are connected with the ammine ligands by a hydrogen bonded three-dimensional network involving all their N, H, and O atoms. The repeating unit of this network is a N40 4(m-H)12 cube with N -H = 1.19(2)A and O -H = 1.98(2)A . Raman and IR spectra were recorded between 150 and 4000 cm -1. A ll the expected internal m odes of the com plex ions could be detected and assigned. The crystallographically different C 104 anions have nearly the same vibrational spectra, only a slight splitting o f two IR m odes is observed. | | |
Reference
| Z. Naturforsch. 49b, 1163—1168 (1994); eingegangen am 25. März 1994 | | |
Published
| 1994 | | |
Keywords
| Zinc Am m ine, Perchlorate, Cubic Structure, Hydrogen Bonds, Vibrational Spectra | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_B/49/ZNB-1994-49b-1163.pdf | | | Identifier
| ZNB-1994-49b-1163 | | | Volume
| 49 | |
22 | Author
| Hendrik Möller, Ellen Suchanek, HeinzDieter Lutz, Werner Paulus | Requires cookie* | | Title
| Neutronenbeugungs-Untersuchung von M g(I03)2*4H 20 -Einkristallen Neutron Diffraction Studies on M g (I0 3 )2 -4H 20 Single Crystals  | | | Abstract
| The crystal structure of M g (I 0 3)2-4 H 20 has been determined by neutron single crystal diffraction (P2j/c, Z = 2, R = 2,2% on the basis of 1107 observed reflections). M g (I 0 3)2-4 H 20 forms a layered structure built up of octahedral M g(H 20) 4(I 0 3)2 units linked by hydrogen bonds. The two crystallographically different water m olecules are in volved in asymmetric, nearly linear hydrogen bonds to adjacent iodate ions (vOD of matrix isolated HDO: 2480, 2475, 2425 und 2412 cm -1, IR spectroscopic data, 90 K). The strength of the hydrogen bonds as well as that of other iodate hydrates is discussed in terms o f both the synergetic effect and Brown's bond valences. | | |
Reference
| Z. Naturforsch. 49b, 1334—1338 (1994); eingegangen am 2. Mai 1994 | | |
Published
| 1994 | | |
Keywords
| Magnesium Iodate Tetrahydrate, Crystal Structure, Neutron Diffraction Studies, Hydrogen Bonds | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_B/49/ZNB-1994-49b-1334.pdf | | | Identifier
| ZNB-1994-49b-1334 | | | Volume
| 49 | |
25 | Author
| Masao Hashimoto, Takahiro Isono, Noriko Yomesaka, Haruo Niki, Hiroshi Kyan, Takeshi Hamagawa | Requires cookie* | | Title
| Reorientation of the CC1 3 Group in Chloral 4-Chlorobenzyl- hemiacetal. A Pulsed 35 C1 NQR and X-ray Study  | | | Abstract
| The crystal structure of the title compound was determined at 291 K: monoclinic, space group C^h-P21/n, Z = 4, a = 1693.2(1), 6 = 579.3(1), c = 1232.5(1) pm, and ß = 107.21 (1)°, R = 0.0415. A sharp decrease of of Cl NQR found at T> 270 K for the CC13 group is attributed to the reorientation of the group over a potential barrier of ca. 50 kJ/mol. Intermolecular interactions between the CC13 and the neighboring atoms seem to dominate the magnitude of the potential barrier. T{~ 1 of the 35 C1 NQR of the Cl atom on the benzene ring obeyed the T 2 law well in the range 80 < T/K <270, while at T>280 K it deviated from the T 2 law. | | |
Reference
| Z. Naturforsch. 47a, 293—298 (1992); received July 25 1991 | | |
Published
| 1992 | | |
Keywords
| Crystal structure, Hydrogen bond, Chlorine NQR, Spin lattice relaxation, Atom-atom potential method | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_A/47/ZNA-1992-47a-0293.pdf | | | Identifier
| ZNA-1992-47a-0293 | | | Volume
| 47 | |
27 | Author
| Hiroshi Miyoshi, Keizo Horiuchi, Narumi Sakagami, Kenichi Okamoto, Ryuichi Ikeda | Requires cookie* | | Title
| C1 NQR, *H NMR, and X-Ray Diffraction Studies in a Hydrogen Bonded Complex Na 2 PtCl 6 * 6H z O  | | | Abstract
| The 35 C1 NQR frequencies, spin-lattice relaxation time and X H NMR relaxation time were measured on crystalline Na 2 PtCl 6 • 6H z O at 77-350 K. The presence of three nonequivalent chlo-rine sites found by X-ray diffraction measurement is in agreement with the observed three NQR lines, which have different temperature dependences attributable to differences in the direction of H-bonding with water molecules. The three NQR lines correspond to three kinds of chlorines with different Pt-Cl distances and H-bond directions. | | |
Reference
| Z. Naturforsch. 53a, 603—607 (1998); received October 31 1997 | | |
Published
| 1998 | | |
Keywords
| CI NQR, X-Ray Diffraction, Spin-Lattice Relaxation, Quadrupole Coupling Constant, Hydrogen Bond | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_A/53/ZNA-1998-53a-0603.pdf | | | Identifier
| ZNA-1998-53a-0603 | | | Volume
| 53 | |
28 | Author
| Takahiro Ueda, Shigenori Nagatomo, Hirotsugu Masui, Nobuo Nakamura, Shigenobu Hayashi | Requires cookie* | | Title
| Hydrogen Bonds in Crystalline Imidazoles Studied by 15 N NMR and ab initio MO Calculations  | | | Abstract
| Intermolecular hydrogen bonds of the type N-H...N in crystals of imidazole and its 4-substituted and 4,5-disubstituted derivatives were studied by 15 N CP/MAS NMR and an ab initio molecular orbital (MO) calculation. In the 15 N CP/MAS NMR spectrum of each of the imidazole derivatives, two peaks due to the two different functional groups, >NH and =N-, were observed. The value of the I 5 N isotrop-ic chemical shift for each nitrogen atom depends on both the length of the intermolecular hydrogen bond and the kind of the substituent or substituents. It was found that the difference between the experimen-tal chemical shifts of >NH and =N-varies predominantly with the hydrogen bond length but does not show any systematic dependence on the kind of substituent. The ab initio MO calculations suggest that the hydrogen bond formation influences the 15 N isotropic chemical shift predominantly, and that the difference between the 15 N isotropic chemical shift of >NH and =N-varies linearly with the hydrogen bond length. | | |
Reference
| Z. Naturforsch. 54a, 437—442 (1999); received March 31 1999 | | |
Published
| 1999 | | |
Keywords
| 15 N CP/MAS NMR, Imidazoles, Hydrogen Bond, 15 N Chemical Shift, ab initio MO Calculation | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_A/54/ZNA-1999-54a-0437.pdf | | | Identifier
| ZNA-1999-54a-0437 | | | Volume
| 54 | |
29 | Author
| Takahiro Ueda, Nobuo Nakamura | Requires cookie* | | Title
| Nature of Hydration Water in (±)-Tris(ethylenediamine)cobalt(III) Chloride Hydrate, (±)-[Co(en) 3 ]Cl 3 -/iH 2 0, as Studied by *H, 2 H, and 17 O Solid State NMR  | | | Abstract
| The static and dynamics properties of hydration water molecules in (±)-[Co(en) 3 ]Cl 3 were studied by means of 'H, 2 H, and ,7 0 solid state NMR. By 'H pulsed field gradient (PFG) NMR the apparent diffusion coefficient of mobile water through a micropore along the crystalline unique c-axis was found to be 1.0 x 10~ 9 m 2 s -1 . The 2 H NMR spectrum at 141 K consists of two components, one being a Pake doublet corresponding to a quadrupole coupling constant (QCC) of (226 ± 2) kHz and an asymmetry parameter of the electric field gradient 77 of 0.08 ± 0.01, and another being a Gaussian line with a linewidth of 3.5 kHz. The 17 0 NMR spectrum at 300 K also consists of a narrow Gaussian peak and a broad powder pattern with a second order quadrupole effect corresponding to QCC = (6.3 ± 0.5) MHz and 77 = 0.55±0.02. The broad and narrow components are assigned to water molecules accommodated at general 12g positions and special 2a and 2b positions in the trigonal lattice with space group Plcl. From the ratio of the populations at these positions their potential energy difference was estimated to be between (2.7 ±0.1) and (3.5 ± 0.1) kJmol -1 . The 2 H NMR spectrum at room temperature indicates a finite quadrupole interaction which is attributable to the rapid rotation of water molecule about the molecular C 2 -axis. When the water content exceeds 2.7, the QCC is reduced sharply to (5.0 ±0.1) kHz at 285 K, suggesting that there occurs rapid rotation of water and rapid exchange of 2 H between nonequivalent positions. | | |
Reference
| Z. Naturforsch. 55a, 362—368 (2000); received August 23 1999 | | |
Published
| 2000 | | |
Keywords
| (±)-[Co(en) 3 ]Cl 3, Absorbed Water, Molecular Motion, Hydrogen Bond, Quadrupole Interaction | | |
Similar Items
| Find | | DEBUG INFO
| | | | TEI-XML for
| default:Reihe_A/55/ZNA-2000-55a-0362.pdf | | | Identifier
| ZNA-2000-55a-0362 | | | Volume
| 55 | |
|