Slide 9 of 11
Notes:
(cos ? Isin?) 90 ? coupling(sin?) precession () only component in obs.dir
-2Ix Sy 2IxSz Iy Ix sin?I detect. in x: I
-2IzSy Sx -Sy sin?S -y: S
-2IxSz -Iy -Ix sin?I -x: I
Result for 4 transients: - [ 1/2 Icos ?Isin? sin ?Isin ?
+1/2Scos ?Isin?sin ?Ssin ? ]
Compared to the COSY, the DQF COSY has only half the sensitivity. However, cross peaks and diagonal have the same modulation, and can be concurrently phased to adsorptive line shape! Also, peaks without couplings are removed from the spectra, simplifying diagonals. Both leads t better recognition of signals close to the diagonal, which in practice more than compensates for the sensitivity loss.
