The spin-pinging scheme is a single spin-echo experiment in which the central 180º pulse is applied selectively on a defined spectral region. It has been widely used for efficient selective and band-selective excitation purposes.

Easy implementation on any AVANCE spectrometer using shaped pulses.

The original spin-pinging scheme was proposed by Freeman and co-workers ( 89JMR404-83 , 89JMR198-84 , and 92JMR308-99 ) as a powerful tool for selective excitation. The method offers high tolerance to pulse miscalibration, rf inhomogeneity and other imperfections. The experiment relies on the inversion of transverse magnetization by a selective 180 pulse on which a minimum two-step phase cycle (EXORCYCLE) is applied to select the desired magnetization. Recently, an improved gradient-based version allows to obtain the same results without phase cycling (see SPFGE experiment).

Comparison with DANTE-z scheme and implementation of DANTE-like pulse trains into the spin-pinging scheme has been reported  ( 94JMRA168-106 and 95JMRB153-109 , and 99MRC451 ) < P>Spin-pinging has also been used as a selective and band-selective ¹³C excitation in HMQC and HMBC experiments ( 94JMRA100-111 ). In such experiments, the initial 90 degree ¹³C pulse is replaced by a 90(hard-¹³C)-180(selective-¹³C) cluster. A similar approach has been used by applying the selective inversion pulse before the hard 90 ¹³C pulse ( 94JMRB77-103 ).

Combination of the spin-pinging principle and the excitation sculpting concept ( 00JMR331-147 )

The spin-pinging experiment can be run with minor changes from a predefined parameter set. The only parameter to consider is the selectivity of the selective inversion pulse: The user must define the shape, the duration and the power level needed for a defined excitation profile.

The spin-pinging scheme affords pure in-phase selective excitation without phase distortions in its whole excitation bandwith. This profile is dependent of the shape of the selective 180 pulse.

The spin-pinging scheme can be included as a starting building block in any selective homonuclear 1D experiment.