SIGNAL-TO-NOISE ENHANCEMENT WHEN T-2-NOT-EQUAL-T-1, A NEW INVESTIGATION OF THE PULSE SEQUENCE DEFT

Very long experimental times are necessary in order to obtain NMR spec tra when the observed nuclei present important spin-lattice relaxation times. DEFT sequence allows for reduction of acquisition time though increasing the signal to noise ratio. An analytical approach is propos ed for which optimal conditions of usage has been defined for the spec ial case of T-2<<T-1. To obtain full maximization it is necessary to u se linear prediction. At last a 2D exchange experiment using DEFT is p resented.