Questions tagged [epr-spectroscopy]
This tag should be applied to questions concerning all aspects of electron paramagnetic resonance (EPR) spectroscopy, including the theory behind the technique and its applications in chemistry.
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Directionality of ring current-induced magnetic fields in purines
What would be the directions of ring current-induced magnetic fields in purine-like heterocycles in a strong magnetic field?
Would be the antiparallel state be a default state for these substances in ...
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Grasping the concept of Electronic Spin, Effective Spin and Fictitious Spin
Trying to learn alone some aspects of quantum mechanics is, sometimes, a struggle. Reading the excellent paper by Piwowarska [1] I was hoping to, finally, understand what is the origin of the so-...
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Can one figure out an optical absorption spectrum from EPR data?
I'm wondering if it's worthwhile for me as an optical spectroscopist to read up a bit on EPR. Do EPR signals reveal where, in terms of wavelength, features in the optical spectrum can be expected to ...
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On the definition of eigenframe
While reading the following article,
Elizaveta A. Suturina, Kevin Mason, Carlos F. G. C. Geraldes, Ilya Kuprov, David Parker, Beyond Bleaney's theory: experimental and theoretical analysis of ...
user98623
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Factors to consider to predict EPR
What are the factors to consider when predicting the EPR spectrum of $\ce{Cu(Ox)P(CH3)3}$ where $\ce{OX}$ is the oxalate ion?
I understand that there are several factors to consider for EPR (Electron ...
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How to turn oil into in a gel?
I've seen some EPR experiments where they add gelatin to water with spin-probes in it, as it "hardens" it immobilizes the spin-probes so that you can check effect of tumbling rate on the EPR....
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EPR or NMR sample that will give narrow lines at 4 K
We have made a crossed coil setup (X and Y transmit/receiving coils) with a SQUID pick up loop along Z. I have built a similar CW NMR spectrometer with inductive pickup that can detect Teflon NMR with ...
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How can Spin-Orbit-Coupling allow interactions between states with different multiplicities?
I can understand how spin-orbit coupling generates the hyperfine structures that we see in textbooks but maybe my view that the L + S momenta interacting to generate a third J momentum is too ...
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Assigning structure based on EPR spectroscopy
When given two copper(II) complexes - bis(N-3-chlorophenyl-salicydenaminato)copper(II) and bis(N-3-methylphenyl-salicydenaminato)copper(II) - how can you predict their EPR spectrum and hence their g ...
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What is a possible conventional interpretation of Wilfred Hagen's puzzling Electron Paramagnetic Resonance spectrum?
In searching for a conventional interpretation, Wilfred Hagen of Delft Technical University is stumped by an Electron Paramagnetic Resonance spectrum (aka Electron Spin Resonance spectrum) in "...
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g-tensor and hyperfine tensor for nitroxide spin label with 15N
Does anyone know where I can find numerical data for the $g$ tensor and hyperfine tensor for a nitroxide spin label where the nitrogen-14 atom has been replaced by a nitrogen-15 atom?
I'm really ...
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Is there any magnetic resonance spectroscopy that based on orbital angular momentum?
The different momenta of electron and nucleus are described by different quantum numbers.
(a) l and m$_l$ describe the orbital angular momentum and quantization on its component along an arbitrary ...
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Measured g-factor of a free-radical changing as a function of something. But I cant work out what?
I'm looking at EPR of a paramagnetic organic molecule in solution that has a very stable free-radical signature with gfactor ~2.0035. All good. Except when watching one particular experiment I saw ...
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How to calculate the magnetic exchange coupling in a charged radical complex?
I have a neutral complex with two magnetic centers. For this case it is easy to calculate the exchange coupling as the broken symmetry state is converged properly. But when I am making the complex ...
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Is the g tensor always "parallel" to the (hyperfine) A tensor?
I have a question about the anisotropy of the g tensor and the A tensor (hyperfine splitting tensor) in electron paramagnetic resonance (EPR).
Both tensors are symmetric, and as a result, there is for ...
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