How to Reference the Scale
You can change the scale reference at any time. We suggest, however, that you perform this operation, when possible, on the spectrometer. In this way all your data will remain consistently referenced (iNMR never changes the original files).
There are many ways to calibrate the frequencies
- Right-click the reference peak. From the contextual menu, choose Reference Scale.
Insert the correct frequency value for your peak and click OK.
- If you are referencing the spectrum against a solvent peak, you can choose one of the stored values from the menu.
- In the case of a homonuclear correlation spectrum, both frequency axes are corrected by this operation. In the heteronuclear case, only the horizontal axis is corrected. The following method can be used to calibrate the vertical axis.
- Put a mark at a frequency whose value you know.
Create a vertical mark (with Alt Gr-click or command-click) to calibrate the X axis or a horizontal mark (with option-click)
to calibrate the Y axis. Choose Format > Axes & Scales, click Reference and continue as above.
- This method can be more accurate because iNMR uses the exact position of your mark instead of searching for the maximum of the nearest peak. Drag the mark exactly in the middle of your reference peak.
- If you know the position of the transmitter (the center of the spectrum) along the ppm scale, you can directly choose Format > Axes and Scales, then click Reference and so on.
- If you have already calibrated the scale in another window, and if the document you are working on
has the same spectral width, you can copy the calibration.
- Choose Format > Axes and Scales, click Reference, then choose the reference window from the menu at the bottom.
- You can copy the reference from one document to many other open documents with a single operation.
- Select the reference document window.
- Choose Format > Overlay.
- Select the checkboxes on the left to select the documents whose scale you want to correct or select the shortcut “All Windows”.
- Click Force Same Scale.
- You can use the console command refer.
- The Process > Process Folder dialog also provides the functionality of the refer command.
Should you need to change the values for the spectrometer frequency and the spectral width, open the dialog Edit > Metadata.
How to Customize the List of Solvents on the Mac
- Copy the file /Applications/iNMR/Contents/Resources/txt/solvents.txt into the folder ~/Library/Application Support/iNMR/.
- Modify the copy.
Related Topics
Comparing Two Spectra in Two Windows
Generating the List of Chemical Shifts and Coupling Constants