Znorg. Chem. 1984, 23, 2528-2532
2528
N M R line widths observed for the present series of compounds are uniformly broader in DMF than in the less viscous solvent MeCN. The line widths for the IS3W ( I = l / J resonances for the limited range of binuclear and trinuclear tungsten species examined (Table IX) are rather difficult to measure accurately. The low sensitivity of the IS3Wnucleus frequently means that only a limited number of data points define the signal after a reasonable data collection time (10-30 h for [W] = 0.5 M), and this leads to large uncertainties in line width measurement. However, the effect of the quadrupolar C u nucleus on the IS3WN M R line widths (Hz) can be discerned as follows: [WS412-,
