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

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The discussion centers on an experiment involving DPPH, a chemical salt, to study Electron Paramagnetic Resonance (EPR) or Electron Spin Resonance (ESR). Concerns are raised about the impact of using a higher frequency, specifically 1800 MHz, on experimental outcomes. It is noted that the typical resonance frequency for DPPH falls between 35 to 75 MHz, suggesting that 1800 MHz is significantly outside this range, which may result in no observable effects. The potential for ionization of DPPH at this frequency is also questioned, with advice to calculate the energy associated with the RF frequency and compare it to the ionization energy of the compound. Additionally, suggestions for improving presentation clarity are offered, including terminology adjustments related to the application of magnetic fields and pulse orientation. Overall, the discussion emphasizes the importance of resonance frequency in EPR experiments and the need for careful consideration of experimental conditions.
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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
 

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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.
 
hagopbul said:
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

Your question was,

The question that I have in my mind that if I use 1800 MHz (The magnetic field F) will I have the same result and can the DPPH or one of its atoms become ionized when I use a 1800 MHz.
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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