Copying peaks between related spectra

Propagating assignments between peaks by manually selecting them, although sometimes necessary, can be tedious if you have large number of peaks that are equivalent and have closely matching positions. In this instance Analysis provides a utility to compare all of the peak positions in two related spectra and transfer the resonance assignments efficiently, whilst still leaving sufficient scope for human intervention. 

In this exercise we will transfer the amide assignments from the peaks in the HSQC experiment to the HSQC_II experiment. In the main menu we select M: Assignment: Copy Assignments. In the Assignment: Copy Assignments popup ensure that the first "HQSC" experiment is set as the "Source Peak List:" and that the second "HQSC_II" is set as the "Target Peak List:". In the top table you will see a list of the source peaks, together with an indication of how many destination peaks they match, within the given tolerances:

Note that when the "Follow Peaks?" option is set clicking on a source row will cause the peak to be highlighted in a relevant window (window1). Also, selecting the source will display the potentially matching destination peaks in the lower table. Clicking on a target row will, as before, highlight the relevant peak.

This utility can be used in one of two ways. One can manually choose the correct destination for each source peak and [Assign Selected Target], or if you trust the completeness and accuracy of the destination one can automatically assign the closest destination peak to each source one with [Assign Singly Matched]. When taking the more automated approach it is common to start with strict tolerances to assign the more certain matches and then relax the tolerances to fill in the remainder.

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