Friday, July 19, 2013

Understanding NMR Spectroscopy

Undergraduate students are typically introduced to the subject of NMR spectroscopy through the organic chemistry curriculum where, after a brief introduction to the technique, they learn how to interpret chemical shifts, coupling constants and NOE's in terms of chemical
information. Unfortunately, this is often the extent of a students training in NMR despite the fact that many who pursue graduate studies use NMR spectroscopy every day.  These students learn to operate NMR spectrometers and will agree that NMR spectroscopy is by far the most valuable technique for characterizing their chemical compounds yet most lack a fundamental understanding of the technique.  It cannot be disputed that an understanding of the fundamentals of NMR enables the chemist to become a confident, knowledgeable NMR user able to gain the maximum amount of information from NMR results.

In my opinion, by far, the best NMR book devoted to the fundamentals of NMR spectroscopy published in the last 10 years is James Keeler's book, Understanding NMR Spectroscopy (my copy is well worn).  Although it is limited to spin-1/2 nuclides and does not cover solid state NMR, it covers the fundamentals of NMR in a very clear understandable way.  Keeler has a talent for teaching and makes the material accessible to all with a basic science background.  After studying this book the reader will gain a much better understanding of one- and two-dimensional pulse sequences, product operators, relaxation, nuclear Overhauser effects and coherence selection through both phase cycling and pulsed field gradients.


In addition to the book, a detailed set of notes is available on Dr. Keeler's web site and recently, an entire course given by Keeler, consisting of 14 lectures, has appeared on YouTube.  Links to the lectures are as follows:

1.                 Energy levels
2.                 The Vector Model
3.                 Fourier Transformation
4, 5, 6          Product Operators
7, 8              Two-Dimensional NMR
9, 10, 11      Relaxation
12, 13, 14    Coherence Selection

I highly recommend the book, and the lectures.  Never has understanding NMR spectroscopy been more accessible.