Origins of Biological Magnetic Resonance

resonance (NMR) spectroscopy” were cited in the award of the Nobel Prize for Chemistry to Richard Ernst. In his Nobel lecture,Ernstconcluded,“Iam notaware ofany other field of science outside of magnetic resonance that offers so much freedom and opportunities for a creative mind to invent and explore new experimental schemes that can be fruitfully applied in a variety of disciplines” (3). Ernst’s lecture also summarizes how this technique of the latter half of the 20th century grew out of developments in physics in the first half of the century. Revolutions in magnetic resonance have continued during the 50 years since the first publications, and these revolutions have maintained a steady influx of new practitioners. I was an undergraduate at Stanford in the late 1950s, and it would have been difficult to avoid getting caught up in the excitement of the new discoveries on the campus and atnearbyVarian.At thattime,FelixBloch turned out each fall to participate in the Physics Department picnic to welcome new physics students. The colorful chemistry professor, Richard A. Ogg, introduced me to NMR, and I remember his declaration: “Do you students realize what this is going to mean to the field of chemistry?” He had just delivered a lecture describing the first observation of resolved chemical shifts in ethanol (4) and his own measurements of proton transfer rates in liquid ammonia solutions (5). Scrupulously dry liquid ammonia gives a proton NMR signal of three lines because, although the three protons of ammonia are equivalent, they reside on nitrogens with one of three different nuclear moments. However, traces of water, in liquid ammonia, lead to reaction [1]; by which