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Molecular Motion of [(CH3)3NH]⊕ Ions in Solid Trimethylammonium Hexahalometallates(IV) as Studied by 1H NMR and 35Cl NQR

1982; Volume: 86; Issue: 7 Linguagem: Inglês

10.1002/bbpc.19820860722

0005-9021

Ryuichi Ikeda, Rainer Kadel, Alarich Weiß, Nobuko Ishida, Daiyû Nakamura,

Organic and Molecular Conductors Research

Abstract The temperature dependence of the 1 H spin‐lattice relaxation time, T 1 , and of the second moment of 1 H NMR spectra were studied in a series of trimethylammonium hexahalometallates(IV), (triMA) 2 MX 6 , (M = Pt, Sn, Te; X = Cl, Br, I). From X‐ray powder diagrams taken at room temperature, it was found that these complexes are isomorphous throughout the series. The unit cell dimensions were determined. A single 35 Cl NQR line was observed for (triMA) 2 SnCl 6 and for (triMA) 2 TeCl 6 in agreement with the crystal symmetry of these complexes. By 1 H NMR, two kinds of motions of the ion (triMA), a) the intraionic reorientations of the CH 3 groups and b) the reorientation of the whole cation about its C 3 axis, have been observed separately in most of the complexes studied. The activation energies of these motions imply that the ions (triMA) are more freely rotating in the hexahalometallate(IV) complexes as compared to the (triMA) halides.