NMR multi-dimensional method for measuring coupling constants within several coupling networks

摘要

This invention provides a NMR multi-dimensional method for measuring coupling constants within several coupling networks. At first, a 90° hard pulse was performed to flip the magnetization from the Z axis to the XY plane. After t₁/2, a selective 180° pulse is implemented with a simultaneous Z-direction gradient, thus reversing different protons at different slices. Then the PSYCHE element is implemented. After another t₁/2, the gradient G₁ and G_p are implemented. At last, the EPSI readout is used to simultaneously record both the chemical-shift and the spatial information. As a result, from different specific slices, we can extract the scalar couplings between the proton reversed at this slice and other protons. These couplings lead to splittings in the indirect dimension, from which relevant coupling constants can be measured.