Inversion-recovery experimental method

The most popular, and also a very accurate, experimental method for measuring nonselective spin-lattice relaxation-rates is the inversion recovery (180°-r-90°-AT-PD)NT pulse sequence. Here, t is the variable parameter, the little t between pulses, AT is the acquisition time, PD is the pulse delay, set such that AT-I- PD s 5 x T, and NT is the total number of transients required for an acceptable signal-to-noise ratio. Sequential application of a series of two-pulse sequences, each using a different pulsespacing, t, gives a series of partially relaxed spectra. Values of Rj can... 

The latter technique is particularly appreciated by coordination chemists because of its simple mathematical formulation and the limited amount of experimental data to be collected (longitudinal relaxation times at a single magnetic field obtained by the inversion-recovery method (Void et al., 1968)). However, the a priori choice of a reference distance (rref) requires a partial modeling of the complex and the extracted distances strongly depend on the accuracy of this original choice. 

There are a number of different experiments devised for the determination of the longitudinal relaxation times of nuclear spins [2] although only the most commonly applied method, inversion recovery, will be considered here. The full procedure is described first, followed by the quick-and-dirty approach which is handy for experimental set-up. 

Check it 5.2.7.2 demonstrates the experimental Tj determination using the inversion recovery method as a pseudo 2D experiment and the separation of the resulting serial file into the corresponding ID files. 

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