The Motion of the OH Group in p-Chlorophenol and its Influence on the 35C1 NQR Parameters*’ **
نویسنده
چکیده
The 35C1 NQ R transition frequencies and the spin-lattice relaxation times, T{, for both lines in p-chlorophenol have been measured in the temperature range 9 0 3 1 0 K. The frequency differ ence and the temperature derivatives for both lines clearly show the existence o f two temperature intervals with distinct lattice contributions to the EFG. Similarly, 7", data show a normal be haviour due to spin-phonon interactions up to 240 K. Above this temperature T { begins to shorten in an exponential manner. The hindered motions o f the OH group are proposed as responsibles o f these effects, and an activation energy o f 26 kJ m o r 1 is determined.
منابع مشابه
35 C 1 NQR and X - Ray Studies of Hexachloropalladates A 2 PdCl
The 35C1 NQR frequencies o f A 2PdCl6 were studied. For A = (CH3)4N + a clathrate [(CH3)4N]2PdCl6 Cl2 was found and its crystal structure was determined (F d3c, Z = 32, a = 2554.5 pm, R = 0.062). The clathrate [(CH3)4N]2SnCl6 Cl2 was prepared, too. It is isomorphous with the corresponding palladium salt. The results o f the 35C1 NQR studies are discus sed on the basis o f the crystal structure.
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