Homonuclear covariance transformation in solid-state NMR!

Covariance (Cov) transformation helps us to reduce the data collection time in homonuclear correlation solid-state NMR experiments such as NOESY and INADEQUATE. In these experiments, large number of t₁ points are usually required to achieve sufficient spectral resolution in the indirect dimension. For example, fully collected Fourier transformed (FT) spectrum of L-histidine monochloride was obtained with 512 t₁ points (A). When the number of t₁ points was reduced to 40 (B), significant wiggle was observed, resulting in very low resolution. Cov spectra (C) of 40 t₁ points (C) produces a spectrum almost identical to (A). Cov achieves more than 10 times reduction of experimental time!

Reference

J. Magn. Reson. 171 (2004) 277-283.