Processing
NMRium offers the possibility to perform a Fourier transformation (FT) on the raw data of one-dimensional NMR spectra. To process an FID, open the FID by dragging it into the Drag and drop here box (section 2). NMRium automatically performs zero filling and then Fourier transformation. Phase correction is also performed automatically. You have the option of viewing all automatically performed work steps. Open the processings panel to view the individual steps. You can reversibly undo a step by removing the tick in the corresponding line or setting it again. To permanently remove a step, click on the recycle bin symbol in the corresponding line. The step is deleted. If you remove all tick
Fourier transformation
To prepare the FID for the Fourier transformation, click onto the Zero Filling icon to the left of the spectrum. Set the desired values for Size (zero filling) and Line Broadening (exponential window function) and click Apply. Then start the Fourier transformation by clicking on the FFT Filter button to the left of the spectrum.
If you are unsure which values to set, you can use the following recommendations as a reference:
Size: Choose twice as many points as in the original FID.
Line Broadening (LB): Specify 0.3 Hz for ¹H spectra and 1-3 Hz for ¹³C.
NMRium has a live function. If you edit the raw data, you can see the changes directly. The changes are only saved when you click on the Apply button. If you want to hide the live function, uncheck the Live function above the workspace. This function is also available for many other NMRium functions.
Phase correction
Click the icon Phase correction to the left of the spectrum. You can choose between manual and automatic phase correction.
Click the Apply button, the phase will be corrected automatically.
You can perform zero-order and first-order phase correction.
For zero-order phase correction, click and hold the green PH0 button above the spectrum. By moving the mouse to the left or right, you can perform the phase correction until the signal is correctly phased and release the button. By double-clicking, you can move the pivot point (red line) for the first-order phase correction.
Repeat the process for the first-order phase correction by pressing PH1 and moving the mouse. The focus should be on the signals that are furthest from the signal marked by the pivot point. Clicking the Apply button completes the phase correction.
Baseline correction
Click the icon Baseline correction to the left of the spectrum. You can choose between two algorithms: polynomial and AIR PLS.
- To use the algorithm polynomial, you may define a degree and then click apply.
- To apply the AIR PLS algorithm, you may define both a maximum iteration and a tolerance range and then click apply.
The different processing steps are explained in the following sections: