How to measure coupling constants? The Crosshair Tool

The Crosshair: These two orthogonal lines forming a crosshair are available on the 'View' menu (or by pressing the <c> key) for reporting positional information, and for help in visualizing peak alignments. This tool can also be found on the 'Zoom' toolbar .

How to measure coupling constants?

The crosshair includes information about the chemical shift and the intensity of the peak (as you can see in the picture below) and also allows the user to measure distance between peaks (or coupling constants) by clicking on the left mouse button and dragging to the desired peak. Activating the crosshair tool will open a 'Cursor Info' dialog box, where the user will be able to see the units distance expressed in ppm, Hz or points. This dialog box will also display the distance between the desired peaks, as well as the intensity ratio. The info View window also contains information about the Spectrum Resolution.

Click on the 'Copy' button to copy to clipboard the information displayed in the 'Cursor Info'.

The cursor will "ride" along the 1D-NMR spectrum simplifying the location of peak maxima and minima by pressing the 'Shift’ key.