The phase-inverted echo-amplitude detected nutation (PEA-Another parameter for labeling individual EPR transitions NUT) experiment for the measurement of transient electron spin is the transition moment, which is in general different for nutation frequencies is introduced. In this new pulse sequence, different transitions. A recently introduced approach that nutation refocused to a rotary echo is detected via the amplitude makes use of the transition moments to spread an EPR specmodulation of a primary electron spin echo. Since detection and trum into a second dimension is forbidden-transition-labeled excitation of the nutation are fully separated in time, experiments EPR (FORTE) (3). FORTE is based on a hole-burning at very high nutation frequencies become feasible. The nutation experiment and allows the separation of allowed and forbidfrequencies which are proportional to the transition moment of den EPR transitions. Another scheme makes use of the proan EPR transition can be used to label individual EPR lines by portionality between the transition moment and the frean additional parameter. Using a two-dimensional PEANUT exquency at which an electron or nuclear spin ensemble nutates periment which correlates the nutation frequencies with the resonance fields, the interpretation of complicated field-swept EPR under microwave (MW) or radio frequency irradiation spectra can considerably be simplified. A theoretical description (4, 5). In NMR and NQR spectroscopy, transient nutation of the experiment is given and the inner working of the approach is experiments are frequently used to elucidate quadrupolar described. The predicted features of PEANUT spectra are verified interactions of nuclei with half-integer spin (6), whereas in experimentally and examples of applications to both ordered and pulse electron nuclear double resonance, where the nutation disordered systems are given.