Peak Analysis

Peak Picking

See the section Peak Picking in Using Spectral Windows for information on how to pick peaks.

Peak Analysis

This panel can be displayed by selecting "Peaks" from the "Analysis" menu of the control panel.

Move
Menu for moving through the peak list.
First
Move to the first peak in the active peak list.
Previous
Move to the previous peak in the active peak list.
Next
Move to the next peak in the peak list
Last
Move to the last peak in the peak list.
Edit
Menu for editing the peak list.
List
Display's a panel with attributes describing the current peak list.
Compress
Compresses the peak list by permanently removing peaks that have been marked for deletion. After compression, deleted peaks cannot be restored!
Cluster
Display's a panel with controls for clustering peaks. NOT YET ACTIVE
Couple
Display's a panel, with controls for coupling peaks.
ID
Displays a Peak Identification panel with for identifying peaks. Particularly useful for identifying noe peaks.
Fit
Extract data about the peak from the dataset and send it to the XY analysis routines for peak fitting to the model currently selected in the XY equations control. The non-linear fit is performed and the peak data updated.
Restore
Resets the displayed peak attributes to those present prior to typing in the peak fields. After the return key is hit, the change's are permanent and can't be restored with the "Restore" function.
The data display portion of the Peak Analysis window displays data about the current peak. New values can be entered in each field. After typing in a new value, you must hit the Enter key to make the change. The newly entered data will be saved immediately to the database. The fields are as follows:
Atom Lab
Enter a value here to assign a peak. The entry must conform to the format of a peakSpecifier, for example, 3.ca. or must be a question mark "?" if the peak is unassigned. Tentative assignments can be entered by preceding the peak specifier with a question mark. For example, ?3.ca.
Center
The chemical shift at the center of the peak.
Width
The half height peak width.
Bound
The width of the peak at its base (the contour level active when the peak was picked).
J
The splitting of the peak in this dimension. This is generally, only specified after the peak coupling action.
LinkA
Not yet active, this will specify a link to another peak with the same label.
LinkB
Not yet active, this will specify a link to another peak with the same label.
Thread
Not yet active, this will be a unique number for all linked peaks.
Error
The error code returned when the peak was picked.

Peak Coupling

Use this panel to collapse pairs of peaks that differ by less than a specified chemical shift difference (in Herz). Typically, a value larger than the expected coupling is specified in one dimension, and a value larger than the expected error in peak position is specified in the second dimension. When used on small couplings (typically less than 20 Hz) the Min value is left at 0.0 for each dimension. In systems with large couplings, for example the 1-bond Ha-Ca coupling in peptides the Min value for the dimension with the large coupling can be set to a value just smaller than the smallest expected coupling. For example, 120 Hz, for a Ha-Ca coupling. Only crosspeaks that differ by at least the Min value will be collapsed to a single peak. This aids in recongnizing the appropriate pairs in complex spectra. If the "Antiphase" button is selected only pairs of peaks with opposite phase will be collapsed. This provides additional selectivity. Two collapse 2D proton COSY spectra this coupling process can be repeate several times, swapping the two Max values each time, to succesively collapse complex multiplets.

Peak Reference Data

Peak Identification