SPIN-7 2 NUTATION AND HAHN-ECHO AMPLITUDES IN MODEL COMPOUNDS AND APPLICATION TO THE TETRAHEDRAL CLUSTER CO-4(CO)(12)/

Spin-7/2 central line intensities are calculated for any ratio of the quadrupolar coupling constant to the radiofrequency field for both one -pulse and two-pulse Hahn-echo experiments and tested by Co-59 NMR on the model compounds, Na-3[Co(NO2)(6)] and trans-[Co(en)(2)(NO2)(2)]NO3 . The Hahn-echo sequence is then used to obtain the quadrupole couplin g constant and asymmetry parameter on a powder sample of Co-4(CO)(12). This technique is found to be particularly useful when the NMR spectr um is broad and featureless. (C) 1997 Elsevier Science B.V.