NMR Spectroscopy: Preparing a Sample



NMR Spectroscopy: Preparing a Sample

Background Reading

Derome, A.E. Modern NMR techniques for chemistry research; Pergamon Press: Oxford, 1987.

Harris, R.K. Nuclear Magnetic Resonance Spectroscopy; Longman: Essex, 1986.

Hornak, J.P. Basics of NMR, , 2003.

Preparing a sample

For the neat liquid compounds pipet 5-6 drops into a clean NMR tube. Dilute the sample with perdeuterated solvent until the solution fills approximately 3 cm of the NMR tube. For the solid organic compound place 10-15 mg of solid in a clean 1 dram glass vial and dissolve in a minimum of perdeuterated solvent. Transfer the solution to a clean NMR tube by pipet and fill the tube to a height of 3 cm with solvent. Place the plastic cap over the end of the NMR to prevent evaporation.

Note: It is very important to avoid contamination of the chemicals and solvents used in this experiment. Never pipet directly from a stock reagent bottle!

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Perfect amount of sample.

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Too much sample. Instrument will not lock.

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Waaaaay too much sample. Instrument will not lock.

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Too little sample. Instrument will not lock

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