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Adding the Projections around a 2-D Plot

A 2-D plot becomes more readable if you add the corresponding 1-D spectra around the borders. If acquired independently, they are called external projections: this is the best solution. In their absence, you can generate the projections from the 2-D plot itself. They are called internal projections in this case.

How to Add the External Projections:

Step 1

Open the 1-D spectra to add. In the case of a homo-nuclear correlation 2-D experiment, a single spectrum is enough for both projections.

Step 2

Return to the main plot and choose Format > Overlay.

Step 3

You will see the list of the other windows. Check the box at the left of the projections.

Step 4

Adjust the amplification factors (they are reported into the last column). You can press Fit Intensity, for an automatic amplification, or you can use the little arrows, or you can set the numerical value.

Step 5

Close the dialog.

Step 6

The projections fill the empty borders (where there's no frequency scale). To move them to a different border, it's enough to change the borders where the scales are depicted. Choose Format > Axes & Scales, click Units, etc...

Step 7

When the dialog is closed, you can still change the relative amplification of a projection with the mouse wheel (move the mouse over the projection to amplify). If you have no scroll wheel, use the keys * and /. The latter shortcuts, however, only work with the last projection of each document.

Step 8

You can drag the four borders with the mouse to leave more or less space, around the plot, for the projections.

Step 9

You can insert an empty space between the main plot and the projection: open the iNMR preferences, reach the second panel (Display) and set the parameter called “Gap under the Projections”.

With an identical mechanism you can combine two or more 2-D spectra, perfectly aligned, into the same plot. For example: a COSY, a TOCSY and a NOESY of the same sample.

Internal Projections

You can generate an internal projection with the command Collapse.

Doing it manually is a time consuming operation. It's convenient to use the ready scripts “projxy” and “projxyplus” available into the web library.

How the Projections are Amplified

The Overlay Manager contains three parameters for the task. Two of them are visible in the bottom-right corner. The first amplifies the horizontal projection; the second amplifies the vertical projection. It's not enough to type their values; you must also click the button “Apply”. The third parameter is the amplification of the overlay (see point no. 4 here above). It amplifies both projections.

Related Topics

Visualization of n-D Spectra

Creating a Poster


Web Tutorial

Visual Guide to Projections and Traces