Correcting Nasty Phase Anomalies
This arrayed experiment is impossible to phase-correct with normal processing. Being here a single signal, the first-order phase correction is not required. It has been observed that the first row (whose index is 0) requires a correction of 27°, the second row of 268°, the third row of 25°, while all the other rows can be corrected simultaneously with a value of 45° for the zero-order phase correction.
This is how you can process this spectrum with iNMR:
- Transform and phase correct with the correction that's good for most of the peaks (45°).
- Pretending that all is OK, go on and correct the baseline.
- Reload the FID with File > Reload.
- Open the console - if it's already open, give it the command:
- Type and Run the commands shown in the picture below.
- Save the script into the spectrum itself (click the round icon with the hard disc).
Here is the complete script with comments:
-- FT + global phase correction: wft() -- additional local phase corrections: phrow(0,27) phrow(1,268) ph(2,25) -- baseline correction: abc()
The command phrow has been introduced with version 3.3.6. It can receive 3 parameters: the row index, the zero-order and the first-order phase corrections. You can find the optimal parameters by manual phase correction, looking up at the numerical values that appear inside the phase correction panel.
Starting with version 3.3.7, the script saved in this way is auto-running. This corresponds to what you normally need. To prevent the script to run automatically when you open the document again, you can use the command cw().