T e tra a lk y la m m o n iu m T e tr a c h lo r o th a lla te s ( I I I ) ; X -R a y , 35C 1 -N Q R , a n d XH -N M R S tu d ie s The crystal structure of (CH3)4NT1C14 and (C2H5)4NT1C14 was determined at room temperature by single crystal technique. (CH3)4NT1C14: D^-Cmmm; Z = 2; a = 913.2pm, fe = 894.6 pm, c = 752.5 pm; (C2H5)4NT1C14: Ct-P63mc; Z = 2; a = 827.9 pm, c = 1329.8 pm. (C2H5)4NT1C14 is isomorphous with (C2H5)4NInCl4. The compounds undergoe a phase transition at 239 K and 222 K, respectively. For both compounds no Cl NQR signal was observable in the high temper ature phase I due to the dynamics of the anion. The 3 Cl NQR was studied in the low temperature phase II of both compounds as a function of temperature. (CH3)4NT1C14 shows a two line, (C2H5)4NT1C14 a four line spectrum. The possible phase II structures and the dynamics of the cation, studied by 'H-NMR, are discussed.

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