KIN HEHAHA SEQUENCES, HETERONUCLEAR HARTMANN-HAHN TRANSFER WITH DIFFERENT BANDWIDTHS FOR SPIN-I AND SPIN-S

A new class of heteronuclear Hartmann-Hahn experiments that is based o n the simultaneous irradiation of two different multiple-pulse sequenc es is introduced. For these ''kin'' HEHAHA sequences, the scaling prop erties of the effective heteronuclear coupling constants are analyzed. Four kin sequences are presented with a ratio of the active bandwidth s Delta nu(I)/Delta nu(S) ranging between 1/2 and 1/10. The offset dep endence of the polarization-transfer efficiency is examined experiment ally and with the help of numerical simulations. (C) 1997 Academic Pre ss.