Single-scan 2D NMR correlations by multiple coherence transfers

A new scheme for the acquisition of heteronuclear 2D correlations in NMR spectroscopy within a single scan, is proposed and demonstrated. The principles of this new scheme resemble those of Mansfield's "k-space walk" proposal, in the sense that they rely on repetitively transferring spin coherences back-and-forth between the two spin systems to be correlated. It is shown that if properly executed, these transfers enable the equivalent of a continuous sampling of the time-domain space supporting a 2D heteronuclear single-quantum correlation NMR spectrum. Details on how to execute the resulting "time-domain walk" experiments are given, and examples comparing it against conventional and other single-scan 20 acquisition alternatives are shown. Advantages, opportunities, and main drawbacks of this new ultrafast approach to 2D NMR, are briefly discussed. (C) 2009 Elsevier Inc. All rights reserved.