MECHANISM FOR THE HARMONIC PEAKS IN THE 2-DIMENSIONAL NUCLEAR-MAGNETIC-RESONANCE CORRELATION SPECTRUM OF LIQUID WATER

The harmonic peaks along the omega(1) dimension in the two-dimensional COSY NMR spectrum of liquid water are analysed in terms of radiation damping line shape theory. In the case of strong radiation damping, du ring the evolution period the angle theta(1), which describes the devi ation of the magnetization from the B-0 direction, becomes time-depend ent and modulates the 2D free-induction decay in a complicated way. Th us multiple frequencies are introduced into the oscillation of s(t(1), omega(2)), which is the 2D signal after 1D Fourier transformation wit h respect to t(2). The harmonic peaks have been well simulated.