Go out and grab a coffee when the NMR guy is refilling the liquid helium, unless you are willing to risk quick freezing of body parts or catching shrapnel from a surprise tank explosion. (image source: Dephologisticated)

Most of an organic chemist’s physical work appears to the naked eye as an interchangeable set of clear liquids and white powders (that is to say, if they are lucky enough in the lab not to produce brown sludge.) This is because atoms, even entire molecules, are too small to be seen through the lens of a microscope, so chemists must deduce their shape and structure indirectly.  This is achieved with a variety of instrumentation and analytical techniques, most of which output data in the raw form of spectra, wavy lines that with a little experience can be used to paint a high-resolution image of the unseen.  Because atoms and molecules, even gigantic ones such as a protein or enzyme, are smaller than a wavelength of light, they appear under even the most powerful electron microscopes as a nothing more than a fuzzy blob.  Because it’s not part of our human perception, interpreting spectral data is a difficult challenge that chemists face every day starting when they are undergraduates.  Operating the obscure equipment, and the hardware and software interfaces that this entails, is its own sort of challenge.

There are several types of spectroscopy, which is a broad concept that describes any kind of radiation of energy as it passes through a given material.   Mass spectroscopy or Infrared spectroscopy is widely used in organic chemistry, but is mostly good for identifying mixtures.  For instance, a winemaker might use one of these techniques to understand levels of eugenol in their chardonnay and therefore determine how long to toast their French oak barrels  (eugenol is a compound from oak which gives the clove-like aroma and flavor to wine). Ultimately the Mass and IR techniques are too low in resolution to do what most organic chemists really need to do, which is to confirm if the thing you think you made in the lab is what it is supposed to be. Step in, NMR.  Nuclear Magnetic Resonance, the work horse tool of the organic chemist, and therefore the only one I’ll get into much detail with here.  It is said that if the NMR machine is shut down for some reason, then the organic chemist goes home for the day.  (So in my world I guess that makes it a bit like a Starbucks.)

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