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NMR meets MUSICIANS

Demo: CH₃CHO, quartet, good shim

Here you can find a spectrum where the transmitter is set close to the low field quartet signal of the aldehyde proton in CH₃CHO, the shim is good. The doublet of the CH₃ group is far off, folding-in is prevented by the spectrometer audio filter.

In each of the four scans you will hear a slowly decaying tone with typical amplitude modulations resulting from interference. This is caused by the coupling between the aldehyde proton and the CH₃ group and the resulting quartet splitting (J=2.9Hz). The acquisition time is 5.1 sec.