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NMR meets MUSICIANS

Melody "Dr. Schiwago"

An even more realistic emulation of chords on an NMR spectrometer may be achieved by successive playing of tones like it's done on a mandolin or a balalaika. Repeated short spaced excitations of, e.g., the prime and the third are carried out over a longer period, e.g. one full bar of the song. As in the previous cases this requires the employment of a sample consisting of only a single resonance line (acetone in CDCl₃).

Differing to the previous melodies, this song is played by using the tempered tuning with all intervals between successive half tones being equally spaced by a factor of 12th-root(2). The offset frequency intervals are no longer calculated by the program itself due to principal reasons. Instead, a frequency list is employed which extends to more than 700 individual tones. Programming was achieved by first typing the tones of the song using an arbitrary abbreviation like FC1 or FE1 for the tones. "F" stands for frequency, C1 and E1 etc. stand for the tones in the melody if the song were played in C major. Subsequently, all symbols FC1, FE1 etc. were replaced with the appropriate exact frequencies using the pulse program editor. The drawback of this method is that the song may no longer be played in any arbitrary tune but is restricted to a fixed tune.