THEORETICAL-ANALYSIS OF RELAXATION DURING SHAPED PULSES .1. THE EFFECTS OF SHORT T(1) AND T(2)

A detailed theoretical treatment of spin-lattice and spin-spin relaxation effects which occur during the application of long selective pulses is presented. The effects of T1 and T2 on the degradation of the frequency-domain profile are discussed for a wide variety of pulse shapes. The predicted effects are observed experimentally for residual HOD in a 2:1 (v/v) mixture of DMSO/D20. The relaxation effects for a given pulse are dependent on the ratio of pulse length to relaxation time, and differences between pulses are due to the trajectories of the magnetization produced by each pulse envelope. A comparison of the various pulse shapes is presented for aid in experimental design and data interpretation. © 1993 by Academic Press, Inc.