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DPPH (a chemical salt [(C6H5)2N-NC6H2 (NO2)3]) and EPR/ESR

  1. Oct 18, 2007 #1
    I am doing this test on DPPH (a chemical salt [(C6H5)2N-NC6H2 (NO2)3])
    The goal of the experiment is to study The Electron Paramagnetic Resonance or
    The Electron Spin Resonance

    Buy using this way:
    see it in the file

    Attached Files:

  2. jcsd
  3. Oct 19, 2007 #2
    I don't think the higher frequency will matter. I don't know physics like others who might comment, but I'd be more worried about changing values in experiments from degradation due to light or heat. I can help more with presentation. Say "By" instead of "Buy," and you might change "we effect" to "we apply," and then clarify that you apply a polarizing (I think) field, and then you apply a linear pulse. Not sure if those terms are better, but there should be something better for the subsequent idea about the 90 degree orientation. Maybe something about how the magnetization works in a cavity?

    Anyway, no one else is writing so I thought I'd throw-in my thoughts. We're generally interested in how DPPH behaves because we use it in our MRFM experiments.
  4. Oct 22, 2007 #3


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    Your question was,

    What I understand about ESR is that the energy used to change the spin state of the electron in question must be in resonance to be absorbed. If the electron will absorb the RF (magnetic component) energy at 1800 MHz then you will have a result. If the usual energy of this absorption is significantly different than 1800 MHz, and it appears to be so, then nothing will happen. Your frequency range is from 35 to 75 MHz in the table you provided. 1800 MHz appears to be significantly different from this and so even higher level harmonics of the 35 to 75 MHz frequencies will not likely be absorbed in your experiment unless you significantly lower the strength of the static magnetic field.

    You can answer your question about ionizing the compound for yourself if you calculate the energy in the RF energy (you should already know of a relationship between energy and frequency) and compare that to a typical ionization energy of this hydrazide. Watch your units (I would use Electron Volts).
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