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Electron Paramagnetic Resonance (wikipedia.org)
1 point by peter_d_sherman on Nov 25, 2020 | hide | past | favorite | 1 comment



>"Theory

Origin of an EPR signal

Every electron has a magnetic moment..."

(PDS: Perhaps all sub-particles have or can possess a magnetic moment, that is, under certain circumstances, they either become or are subject to magnetism, and perhaps this is related to one or more modes of vibration, at one or more frequencies, at one or more very small points (some very minute fraction of a second, again, depending on frequency) in time...)

[...]

>"In the often encountered case of I = 1/2 nuclei (e.g., 1H, 19F, 31P), the line intensities produced by a population of radicals, each possessing M equivalent nuclei,

will follow Pascal's triangle.

For example, the spectrum at the right shows that the three 1H nuclei of the CH3 radical give rise to 2MI + 1 = 2(3)(1/2) + 1 = 4 lines with a 1:3:3:1 ratio. The line spacing gives a hyperfine coupling constant of aH = 23 G for each of the three 1H nuclei. Note again that the lines in this spectrum are

first derivatives

of absorptions.

Simulated EPR spectrum of the H2C(OCH3) radical

As a second example, the methoxymethyl radical, H3COCH2. the OCH2 center will give an overall 1:2:1 EPR pattern, each component of which is further split by the three methoxy hydrogens into a 1:3:3:1 pattern to give a total of 3×4 = 12 lines, a triplet of quartets."




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