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1981 (1)
1Author    Motoko Kenmotsu, Hisashi Honda, Hiroshi Ohki, Ryuichi Ikeda, Tomoki Erata, Akira Tasaki, Yoshihiro FurukawaRequires cookie*
 Title    Ionic Dynamics in Plastic Crystal KNOz Studied by 39K and I5NNMR  
 Abstract    The spin-lattice relaxation time of 39K N M R observed in the low-temperature phase (T <264.1 K) of K N 0 2 is explained by the quadrupole mechanism contributed from a newly found N O J m otion. The in-plane C 3 reorientation and the overvall N 0 2 rotation as well as the self-diffusion were shown in the intermediate phase (T < 314.7 K) and the high-temperature plastic phase (T < melting point: 710 K), respectively, by observing 39K and 15N N M R relaxation times and 1SN lineshapes. 
  Reference    Z. Naturforsch. 49a, 247 (1994); received July 23 1993 
  Published    1994 
  Keywords    K e y words: Solid NM R, Q uadrupole relaxation, Plastic crystal, Phase transition, Chemical shift anisotropy 
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 TEI-XML for    default:Reihe_A/49/ZNA-1994-49a-0247.pdf 
 Identifier    ZNA-1994-49a-0247 
 Volume    49 
2Author    Hisashi Honda, Shin'. Ichi Ishimaru, Noriko Onoda-Yamamuro, Ryuichi IkedaRequires cookie*
 Abstract    y n a m ic s o f N i t r i te I o n s in th e I o n ic P la s tic C r y s ta l T IN O 2 s tu d ie d b y 15N a n d 205T1 N The temperature dependences of the NMR spin-lattice and spin-spin relaxation times and the NMR spectra of 15N in T115N02 were observed in the plastic phase (282.4 K < T < 459 K) and the low-temperature phase. From the analysis of 15N NMR data, we attributed the motion reported in dielectric and TI NMR studies in the low-temperature phase to the 180°-flip of NO^~ ions which takes place with an activation energy of 14 kJ mol-1. In the plastic phase, we detected isotropic NOJ reorientation with an activation energy of 13.5 kJ mol-1 and a new anionic motion with 10 kJ mol-1. 
  Reference    Z. Naturforsch. 50a, 871—875 (1995); received June 16 1995 
  Published    1995 
  Keywords    Solid NMR, Spin-lattice relaxation, Plastic crystal, Phase transition, Chemical shift anisotropy 
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 TEI-XML for    default:Reihe_A/50/ZNA-1995-50a-0871.pdf 
 Identifier    ZNA-1995-50a-0871 
 Volume    50 
3Author    R. Blachnik, A. Hoppe, U. Rabe, U. WickelRequires cookie*
 Title    Käfigverbindungen im System P 4 S 3 -As 4 S 3 Cage Compounds in the System P4S3-AS4S3  
 Abstract    of P4S3 and AS4S3 were investigated. The system reveals a broad metastable region of solid solubility. At the composition PA83S3 new structures are obtainable after various thermal treatments. In the mixtures six different cage molecules (P4_ x Asa;S3 (x = 1-3)) were found. PAS3S3 is the most stable of the mixed cages. At higher temperature a plastic-crystalline modification, at the composition PAS3S3 two further high temperature modifications are observed. NMR and mass spectra, and d-values of the modifications are reported, and the high temperature behaviour of all mixed cages is described. 
  Reference    Z. Naturforsch. 36b, 1493—1499 (1981); eingegangen am 29. Juli 1981 
  Published    1981 
  Keywords    Phosphorus Arsenic Sulfides, Cage Molecules, Plastic Crystals, Phase Diagrams, Chalcogenides Mixtures 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-1493.pdf 
 Identifier    ZNB-1981-36b-1493 
 Volume    36 
4Author    Roger Blachnik, Ulrike WickelRequires cookie*
 Title    Das System P4S3-P4Se3 The P4S3-P4Se3 System  
 Abstract    The system P4S3-P4Se3 was investigated by room temperature and high temperature X-ray techniques, MS-and 31 P NMR spectroscopy and differential scanning calorimetry. At room temperature the phase diagram contains three regions of solid solubility, one from P4S3 to ca. 45 mole% P4Se3 with the a-P4S3 structure, the second from ca. 48 to 60 mole% P4Se3 of unknown structure, and the third from ca. 65 mole% P4Se3 to P4Se3 with the «-P4Se3 structure. On heating all these phases transform into a plastic-crystalline modifica-tion (ß) with complete solid solubility between P4S3 and P4Se3. For /?-P4S3 d-values are determined with Cr-Kai-radiation. At higher temperatures the /i-phase transforms into a y-phase, which was characterized by high-temperature X-ray methods. Mass and 31 P NMR spectra reveal a multicomponent system consisting of all possible molecules of the type P4S,zSe3_:r (x = 0-3). All samples prepared from the melt are com-posed of a mixture of all these cage molecules. For P4S3 a new modification is found by the DSC measurements. It can be shown that the enthalpy of melting consists of the ß-y transition enthalpy and the real enthalpy of fusion. Metastable y-P4S3 can be obtained over a broad temperature region (ca. 440-405 K) on cooling of the melt; it is probably isostructural with y-P4Se3. For the a-ß and ß-y transi-tions several kinds of hysteresis effects are described. 
  Reference    Z. Naturforsch. 37b, 1507—1513 (1982); eingegangen am 30. Juli/21. September 1982 
  Published    1982 
  Keywords    Phosphorus-Sulfides-Selenides, Cage Molecules, Plastic Crystals, Phase Diagram, Phase Transition in P4S3 
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 TEI-XML for    default:Reihe_B/37/ZNB-1982-37b-1507.pdf 
 Identifier    ZNB-1982-37b-1507 
 Volume    37