2: Chemical Reaction Rates by NMR (Shell and CIT)
My graduate work at CIT involved a spectroscopic study of aqueous mixtures of cuprous and cupric chlorides, whose solutions are much darker than the corresponding single component solutions. It was obvious then that there had to be electron transfer between the metal ions associated with optical excitation. I expected that there should be rapid electron transfer between the ions in the absence of optical excitation. Harry Weaver of Varian Associates and I were able to demonstrate this rapid transfer through studies of copper NMR in these solutions (25). I was still at Shell at the time, but developed the theory of “paramagnetic pulse” reactions shortly thereafter after moving to CIT (31). Our theoretical treatment of this problem used the Bloch equations in a manner first described by Gutowsky et al. After thinking about the general problem of chemical reaction rates I found a much simpler way to convert the Bloch equations for NMR to include the effect of chemical reactions (42), under both steady state as well as transient NMR conditions. These equations have been used subsequently by many investigators.
The Shell to CIT transition
The transition from Shell to CIT was seamless, except now I had to confront budgets, graduate students, and teaching. Teaching at CIT proved to be a pleasure. Working with research graduate students was more of a challenge as they differed widely in background and personality. In contrast, at Shell I mostly worked alone, but did some of the NMR work with established investigators, Charles Reilly, A.D. McLean and C. H. Holm. A young summer visitor at Shell, J. Strathdee, helped me with a theoretical calculation of anisotropic proton hyperfine interactions in pi electron radicals. This proved to be important in later work at CIT on the malonic acid free radical (57).