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NMR experiment to find G-factors

  1. Mar 18, 2012 #1
    Hey,

    I did a small experiment to determine the electron, proton and fluorine nuclei g-factors using a teltron set up shown below. The experiment was set up to sweep the static magnetic field between 0 and 3.67 mT and to keep the frequency of the perpendicular high frequency field constant.

    U18803_01_Basic-Equipment-Set-for-ESR-NMR.jpg

    When using the electron probe and electron target sample, hollow cylindrical cores are placed between the scan coils and interface with pole face rings at the entrance to the sample chamber. The sample chamber is an enclosed box between the two scan coils where the sample sits in the electron probe.

    With this set up I got really good resonance peaks with nothing unexpected.

    Just out of curiosity i replaced the pole faced rings with pole faced discs and reran the experiment.

    It produced these another peak at the end of the sweep which is roughly half the size of the main resonance peak. The best way to explain it would be, after the main resonance peak, there is about 10 ms of minimum, normal output, then towards the end of the sweep the output increases forming an almost linear increase until the magnetic field is maximum. The sweep ends then repeat.

    This peak couldn't correspond to energy transitions because they are only half the size of the resonance peak, if it was an energy transition would the peaks be just as big as the main resonance peak?

    Does anyone know what these peaks might be?

    The only difference between the single resonance peak and the weird results is that I changed the volume of the cavity right?

    I would have posted pictures up as well but the oscilloscope I used wasn't connecting properly to any printers.
     
    Last edited: Mar 18, 2012
  2. jcsd
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