There isn't a unique resonant frequency. If it were always the same independent of the applied field and the molecule, NMR wouldn't work.
Everyone, I realize that the new Bybee thing appears to be pretty crazy. If I have not known Jack Bybee for decades now, and I have NEVER caught him in a lie, I would be doubtful from the get-go, but so far we hear the same thing in the same conditions.
First of all, we both believe that there are audio differences in electronics that remain important. Many of our critics don't, and they assert that everything that I design is sonically just like everything else, but the advantage of my name being recognized by audiophiles (magically) changes my designs to something better sounding. Sorry, it doesn't work that way.
First of all, we both believe that there are audio differences in electronics that remain important. Many of our critics don't, and they assert that everything that I design is sonically just like everything else, but the advantage of my name being recognized by audiophiles (magically) changes my designs to something better sounding. Sorry, it doesn't work that way.
Actually I think Principles of NMR and the background to C-13 NMR spectroscopy provide a good summary.
The carbon isotope in question is paramagnetic. It is slightly more than 1% of normal bits of carbon. The rest mostly isn't paramagnetic.
So coating a wire with a bit of the stuff should produce some changes. Probably extremely small, but not having tried it, I really don't know exactly what would happen. Very small magnetic field, lower then typical MRI resonant frequency and lots of unknowns.
Now what happens in a carbon resistor or volume control due to a bit of the magic isotope is also an interesting question. I suspect it would increase the distortion, but as bad as such resistors actually are the amount might not stand out.
But it was fun to watch you wiggle.
Since they all contain about 1.1% Carbon-13, the more interesting question would be what happens if we eliminate it.
So you never found your magic frequency?
SY's seemed to be about 1 per 30 minutes.
For Carbon 13, one cite for 200-240 Hertz but not really sure that was appropriate. Would however explain why they work for a power line filter.
Normally in MRI in the Mhz range.
That's quite a spread.
The frequency of a nuclear magnetic resonance is dependent on the strength of the surrounding magnetic field. In some forms of NMR the applied frequency of electromagnetic radiation is held fixed while the magnetic field is varied (see continuous wave spectroscopy), in other forms the magnetic field is fixed and the radiation frequency is varied. There is no single fixed resonant frequency associated with an isotope. NMR spectroscopy (and imaging) either requires calibration, or relies on relationships between known absorption frequencies (much like red-shifted absorption spectra of distant stars). The patterns are important, not the frequencies.
OK, so basically you can find links but you have no real understanding of NMR. That's OK- until I had to learn enough to publish papers on it, my knowledge was superficial as well. At the point where you get interested, let me know and I can give you some good fundamental references. Actually learning the stuff is unfortunately more difficult than trolling, though, so be warned.
That's actually only a small part of the spread. The resonant frequency is a function of the applied magnetic field and can vary by orders of magnitude. It all depends on the sort of measurement you want to do.
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