Chemical structures can be added not only to a spectrum or tree node but also to any peak. To add a chemical structure to a peak, click the Assign Structure to Any Peak button  in the Database Manager tool bar. A New Structure Editor will open and you can draw a fragment. After you finish drawing, the program will automatically attempt to connect your structure with a spectral peak according to the fragment's m/z value. If, for whatever reason, you need to connect the drawn fragment to a different peak, simply drag the connecting circle with the mouse to the required peak. The drawn fragment can be resized. Fragments generated by Fragments & Mechanisms window can be assigned automatically to peaks in a spectrum

A structure can also be assigned to a peak using the Data page of the Database Manager window, where all peaks in the spectrum are listed. Click on the line where the peak is listed, then click on the button  in the Fragment column and Structure Editor will open.

Note: Structures assigned to spectral peaks are not searchable.