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Coupling Constant

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    The distance between any two adjacent lines in the NMR peaks of two sets of equivalent hydrogen nuclei coupled only to each other is the same, which, when expressed in hertz, is called the coupling constant (symbol: J) of the two sets of equivalent hydrogen nuclei.


    To convert x, which is in ppm, into the coupling constant, multiply x by the operating frequency, expressed in MHz, of the NMR spectrometer used for the experiment. The x for two sets of equivalent hydrogen nuclei coupled to each other depends on the operating frequency of the spectrometer, but J does not

    see also Pascal’s triangle

    This page titled Coupling Constant is shared under a All Rights Reserved (used with permission) license and was authored, remixed, and/or curated by Gamini Gunawardena via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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