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Pulsed/CW NMR
introduction | the instrument | experiments | prices 
PS2-A is a research grade Pulsed/CW NMR spectrometer capable of carrying out a wide variety of experiments and research projects. In this brief section, we are listing, in no particular order, experiments that instructors might wish to consider for their laboratory programs. This is certainly not an encyclopedic list; rather, it is a collection of experiments that will provide a challenging experience to both undergraduate and graduate students. All of the experiments require a careful reading of the literature to obtain a thorough explanation of the physics behind the experiments.
Representative data for some of these experiments can be found on the Instrument page of this website.
- Measure T1 and T2 of water doped with paramagnetic ions over a wide concentration range. Paramagnetic ions that dissolve in water include CuS04 and Fe(NO3)3.
- Measure T1 and T2 in glycerin and water mixtures.
Glycerin and water mix in any ratio. The motion of the protons in glycerin is significantly changed by the change of the liquid viscosity with the addition of water. The relaxation times can be correlated with the viscosity of the liquid, as well as with the water concentration.
- Measure T1 and T2 in mineral oil with solvents. The relaxation times of protons in mineral oil diluted with organic solvents show the effects of diffusion and correlation times.
Pulse Programmer
- Measure T1 and T2 in Petroleum Jelly
Vaseline is not a solid. The two relaxation times indicate fast molecular motion which is characteristic of a liquid. Samples can be heated and T1, as well as T2, can be estimated as the sample cools to room temperature. Other organic greases with sufficient proton concentrations can also be studied.
- Biological Materials
Most biological materials have protons, usually in water molecules. Measurements of T1 and T2 in biological materials give detailed information about the local environment of these water molecules. This area of exploration is wide open. This might be an area appropriate for an undergraduate research participation project.
- Discover inequivalent fluorine nuclei in the various fluorine liquids that come with the spectrometer; HT-110, FC-43, FC-70, and FC-770.
Look up their chemical structure and identify the various fluorine sites.
Investigations Using Fast Fourier Transforms (FFT)
- "Watch" epoxy cure. Study T1 and T2 of various slow curing epoxies and explain the data.
- Rubber is a peculiar substance. Use various pencil erasers as samples. Study T1 and T2 as an eraser cools. You will have to estimate the temperature, since it is difficult to measure the temperature when the eraser is in the sample coil.
- Can you observe inequivalent protons in ethyl alcohol? What about in an echo sequence?
- Measure spin diffusion in distilled water.
- There are well known fluorine greases. Measure T1 and T2 in those salt solids.
- Examine virgin and recycled TEFLON. Can you distinguish them from their NMR data?
NMR of "Soft" Solids |
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