Assign a peak

Instructions

Assign a peak

Before assigning a peak to an atom or atom type, it is important to understand that a peak assignment ALWAYS is done via a Resonance. A peak can be assigned to resonances for each of its dimensions. The resonances can then in turn be assigned to atom types, atoms, spin systems and residues.

Assign a peak to a resonance

To assign a peak to a resonance, select it and type ‘a‘ on the keyboard, or use the R: Assign: Assign ... option from the options menu. Both these alternatives raise the  Assignment: Assignment Panel (see below). 

A dimension of a (partly) unassigned peak can be assigned to (a) resonance(s) in 2 ways:

• • by creating a new resonance for a selected dimension in the left panel of the "Assignment possibilities" frame, by clicking [<New>].

  • by assigning a dimension to an already existing resonance or resonances from the possible assignments in the right panel of the "Assignment possibilities" frame. To do this, simply click on the possible resonance.

To delete an assignment contribution from a dimension, select the resonance contribution, and click [Clear Dim Contrib]. This only remove the resonance contribution to the peak assignment, but will leave the resonance itself and its assignments unchanged. 

Assign a resonance to an atom type

To assign a resonance to an atom type, select the resonance from the peak assignment and click [Set Type]. This raises Molecule: Atom Browser. To assign the resonance to the atom type do the following:

• • Select the desired element from the "Elements" buttons to display all the atom types for this element.

  • From the list of atoms, choose the type of atom that you want to assign the resonance to. It does not matter from which residue you select the atom type, the assignment is only made to the type of atom, not to a specific residue.

insert atom browser screenshot

If you want to make a stereo specific assignment of an atom type, adapt the settings in the {Options} tab in Molecule: Atom Browser.

Set same spin system

To assign all the resonances assigned to a peak to the same spin system, click [Set Same Spin System]. The spin system of a selected resonance can be deassigned by clicking [Deassign Spin System].  

Deassign a resonance

To remove the assignment of a resonance itself from the "Assignment panel", select the resonance and click [Deassign Resonance] or [Deassign Spin System], depending on which type of information you want to deassign.

Propagate assignments

When several peaks have the same assignment suggestions in common dimensions, it is possible to assign all those peaks by selecting them and clicking on one of them; R: Assign: Propagate assignments. For this, one of those selected peaks has initially to be assigned. This can be used in situations when e.g. navigating from a 2D root peak to an 3D window where we want to assign several peaks 3D peaks in the root dimensions. More about how to propagate assignments are found here.