The use of pulse-ESR and Fourier Transform Techniques

Now that commercial pulse-ESR spectrometers are available, there can be no doubt that this will become a popular instrument, especially for those interested in studies in the time domain. At present, there are no great advantages in the sensitivity, but there probably will be in the near future. Work in this area is covered in two recent books (Reran and Bowman, 1990 Holt, 1989). An important aspect of pulsed ESR techniques is that they can be used to measure spin-lattice relaxation rates specifically. These are generally not obtained from normal CW-ESR spectra, which are frequently insensitive to this parameter. 

Another major development in the field of pulsed ESR is the use of Fourier-transform methods. It is this combination that has led to major improvements in NMR spectroscopy however, unfortunately, it is still of relatively limited use to ESR spectroscopists because of the difficulties involved in covering a wide enough range of field. In this technique, the high-resolution spectrum is recovered by Fourier transformation of the entire time-domain signal after one or several pulses (Angerhofer et al., 1988). 

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