Fourier spectroscopy of nonequilibrium states, application to CIDNP, overhauser experiments and relaxation time measurements

Polarization transfer from para-hydrogen to heteronuclei: Effect of H/D substitution. The case of AA′X and spin systems

“…The results given below are obtained under the hypothesis that no mixing effect occurs due to a non equilibrium state [14]. In a general way, this corresponds to spectra obtained under small flip angle conditions or, as this is here the case in practice, to first order spectra (see Table 1).…”

Extraction of T2 from NMR linewidths in simple spin systems by use of reference deconvolution

“…A small flip angle could be used to prevent possible mixing effects due to the non-selective pulse. 32 Our observations are that best results are achieved when waiting for full recovery of the magnetization between scans. If a better definition of the damped FID sinusoids is necessary, one could perform zerofilling in the frequency domain, followed by inverse Fourier transformation.…”

Fourier-Transform EPR at High-Field/High-Frequency (3.4 T/95 GHz) Using Broadband Stochastic Microwave Excitation

“…Transient systems, after light excitation, are often spin-polarized, i.e., neither time invariant nor in thermal equilibrium. It is known that in this case large flip angles of pulsed EPR would lead to spectra with significant line distortions (34). In contrast to pulsed EPR with large flip angles, stochastic EPR could also be applied to spin-polarized systems without suffering from line distortions.…”