Gutowsky, Herbert Sander
GUTOWSKY, HERBERT SANDER
(b. Bridgman, Michigan, 8 November 1919; d. Urbana, Illinois, 13 January 2000)
Gutowsky contributed decisively to the introduction of nuclear magnetic resonance (NMR) into chemistry. In the early 1950s he participated in research that enabled more powerful elucidation of molecular structure and dynamics and in which NMR was probably the most instrumental technique. Throughout his lifetime he was active in molecular spectroscopy, delving into the phenomenology of new effects and designing novel methodologies.
Early Life and Education . Gutowsky was the second youngest of seven children of German immigrants to the United States, Otto Gutowsky and Hattie Meyer, who owned a farm near Bridgman, Michigan. During the first years of the Great Depression, the Gutowskys sold their property and moved to Hammond, Indiana, where they bought a gasoline station. While in high school, Gutowsky supported himself by delivering newspapers. Inspired and financially supported by his older brothers, Gutowsky chose to study the sciences and entered Indiana University at Bloomington. Fascinated by astronomy, and particularly by the teaching of Frank Kelley Edmondson, he received an undergraduate assistantship. Though greatly impressed by the enthusiasm and intellectual atmosphere in astronomy, he was aware that the economic prospects of a career in chemistry were much better, which persuaded him to opt for a major in that field. In 1940 he graduated with honors. In Gutowsky’s senior year at Indiana, a tutorial on Linus Pauling’s theory of the chemical bond taught by Fred Stitt, a former PhD student of Pauling, had a great and lasting influence on him.
For graduate studies, Gutowsky went to the University of California at Berkeley, where he considered himself a misfit because of his incongruous social background. His research, undertaken with Willard F. Libby in the field of isotope separation, was not successful. In the summer of 1941, as a member of the Army Reserve Officer Training Corps that he had joined at Indiana, he applied for active duty. He spent the next four years working for the Los Angeles subbranch of the San Francisco District of the U.S. Army Chemical Warfare Service. He was responsible for the subcontracting and the supervising of small companies that produced chemical weapons. He left the Chemical Warfare Service with the rank of captain in 1945.
During the war he contracted diabetes (which eventually led to his discharge for medical reasons), and for treatment he occasionally returned to Berkeley. There a young faculty member, the chemical physicist Kenneth S. Pitzer, accepted him as a master’s student. Gutowsky’s studies, on electron deficient molecules, were completed in February 1946. He had investigated the bond types of molecules that have fewer valence electrons than normally required to fill their orbitals. These were compounds whose bonds were not formed by the usual sharing of electrons, but nevertheless were neither ionic nor metal-like. Using the group of aluminum alkyls, Gutowsky and Pitzer observed and explained dimerization: the combination of two identical molecules to form a single one. This was based on the classical method of freezing point lowering, though they also employed spectroscopic evidence available from other research groups. Pitzer, in his general vision of quantum chemistry, emphasized the importance of observable quantities that could be related to the core of a theory based on mathematical equations. Thus, with his master’s thesis Gutowsky undertook the type of study that would remain with him during his entire career: elucidating the electronic structures of molecules with instrumental techniques by making use of advanced theories of the chemical bond.
Having lived in the Midwest and in California, Gutowsky chose for further graduate studies one of the foremost scientific institutions, Harvard University, in Cambridge, Massachusetts. There, pragmatic philosophy had a great impact on science, as so influentially advocated in the interwar years by the operationalism of the physicist Percy W. Bridgman. Bridgman defined the objects of physical inquiry by the operations needed to measure them. This approach was shared by the chemical physicist E. Bright Wilson, formerly Pitzer’s laboratory section instructor at the California Institute of Technology and the coauthor, with Pauling, of a textbook, Introduction to Quantum Mechanics(1935). Wilson explicitly based the criteria for success of scientific theories on their ability to generate explanatory models and afford hypotheses that could be experimentally studied. Foremost, he stressed the scientist’s obligation to achieve control over the effects studied as completely as possible; this was most often achieved with the help of sophisticated instrumentation. Though he was not accepted as Wilson’s graduate student, Gutowsky followed this style of molecular spectroscopy during his entire career. His PhD supervisor, the physical chemist George B. Kistiakowsky, who had taken part in the Manhattan Project at Los Alamos, New Mexico, and later became science advisor to Presidents Dwight D. Eisenhower, John F. Kennedy, and Lyndon B. Johnson, gave Gutowsky a quite unrealistic problem with his first assignment—the structure of the methyl radical—a problem that remained an unsolved riddle for many years to come. However, this project did provide Gutowsky with the opportunity to become familiar with the operational modes of an infrared spectrometer and introduced him to the problem sets and methods of molecular spectroscopy.
Nuclear Magnetic Resonance Spectroscopy . Under pressure to find a suitable subject to complete his PhD thesis, Gutowsky stumbled onto an exciting and novel technique for elucidating molecular structures whose origins lay in war-related radar research and nuclear physics, namely, nuclear magnetic resonance (NMR). It had just been independently developed by Edward M. Purcell, Henry C. Torrey, and Robert V. Pound at Harvard and the Massachusetts Institute of Technology (MIT), both in Cambridge, and by Felix Bloch, William Hansen, and Martin Packard at Stanford University in California. The NMR spectrometer basically consisted of a radiofrequency (rf) generator, a magnet, and an rf detector. NMR is based on nuclear spin, a quantum mechanical effect best visualized as a rotation of the nucleus. Together with the nuclear charge, the spin imparts a magnetic moment to the nucleus. Placed inside a strong magnetic field, some of the nuclei precess in the direction of the magnetic field with a certain frequency, depending on the particular type of nucleus and the strength of the magnetic field applied. In the case of hydrogen, the spin of the protons can have two values, +1/2 and -1/2, corresponding to the existence of two energy levels. If a weaker electromagnetic field is irradiated perpendicular to the direction of the strong magnetic field, and if the frequency of the electromagnetic radiation matches the difference of the energy levels, absorption or emission of radiation occurs: the nuclei are in resonance.
Purcell and Bloch designed NMR as a high-precision technique for the measurement of nuclear magnetic moments, and thus they firmly embedded the technique in nuclear physics. In addition, NMR almost instantly became an important method in molecular spectroscopy, making use of the now reliably and precisely accessible radio frequency range of the electromagnetic spectrum. In particular, the group around Purcell studied the structures and dynamics of solids and, through a contact provided by Kistiakowsky, Gutowsky in late 1947 cooperated with Purcell’s graduate student, George Pake. Pake had just developed an NMR method for studying the relative positions of protons in the crystalline water of solid gypsum that supplemented x-ray measurements. Gutowsky and Pake were supposed to tackle the structure of diborane (B2 H6), one of the electron deficient molecules that Gutowsky had become familiar with during work for his master’s thesis at Berkeley, and a classic problem since Robert S. Mulliken applied a theoretical treatment in 1935. Chemists were unable to decide between two possible structures: a bridge structure, in which two of the six hydrogen atoms are located between the two boron atoms, and an ethane-like structure, with all hydrogen atoms being equivalent. Unfortunately, Gutowsky and Pake’s experiments did not lead to interpretable results, and in 1948 and 1950, respectively, the rival techniques of infrared spectroscopy and microwave spectroscopy settled the question in favor of the bridge structure.
However, in need of interpretable data, Gutowsky and Pake extended their project beyond diborane by investigating structurally related compounds. Here, they made the surprising observation that the broad lines being studied in investigations of solids showed characteristic peaks. (The broadening of the resonance lines was caused by dipolar interactions of the nuclei in a rigid lattice.) Their conclusion was that molecular motions in “plastic” solids narrowed the broad lines. Thus, in searching for a method to study static molecular structures, they additionally found a technique suitable for investigating molecular dynamics, in particular rotational motions in solids. This was a topic of great interest to the chemical physics community of that time, and although their method soon was superseded by the quite different NMR technique of Nicolaas Bloembergen, Purcell, and Pound, it showed the general feasibility of NMR for studying such topics.
During the time that he worked with Pake, Gutowsky was not permitted to tune the instrument. His tasks were those deemed suitable for a chemist: the synthesis of the sample compounds and the design of the cryostat employed to study compounds that were not solids at room temperature. Significantly, throughout his life, Gutowsky felt that chemists were inferior to theoretical physicists, as they were dealing with less fundamental laws in science. Nevertheless, chemists had different research agendas, and they looked for different answers than those sought by physicists. For this reason it was important that chemists become independent of their colleagues in physics with regard to the uses of physical instrumentation. They could achieve this independence only by securing control of the instrument and by being able to interpret the results in chemical, and not only physical, terms.
The Chemical Shift . It was his own professional independence that Gutowsky set out to achieve when, in September 1948, he joined the faculty of the Department of Chemistry of the University of Illinois at Urbana. Initially, however, he had to acquiesce to dependence on others, albeit of a different kind than at Harvard. The reason that he had been hired was not his promise in NMR-related matters, but his experience in infrared spectroscopy. At Urbana, Roger Adams, head of one of the most successful American groups in organic chemistry, clearly recognized the importance of the new spectroscopic methods for research on structures of organic molecules. During the war, organic chemists at the University of Illinois had become used to the benefits of a Perkin-Elmer infrared spectrometer. Gutowsky replaced the spectroscopist in charge of the spectrometer and was assigned to managing a service laboratory for the organic chemists, assisted by a technician. This work made Gutowsky familiar with the needs and expectations of organic chemists. Furthermore, infrared spectroscopy provided a model that could be emulated for the future development of NMR.
In Urbana, Gutowsky planned to build up a research program based on structural studies of solids along the same lines as at Harvard. For that purpose he constructed his own NMR spectrometer, with funds provided first by the Graduate Research Board of the University of Illinois and then by the Research Corporation, a nationwide foundation for the support of basic research. In the late 1940s, the construction of such a high-technology instrument was not an easy task for a young instructor in chemistry. Indeed, after the magnet had been installed in October 1949, it took Gutowsky several months to get the instrument working. In general, problems with the electronic equipment hampered progress, making broad-line studies of solids impossible at first. But in March 1950, the discovery of chemical shifts in NMR spectral lines—independently by Walter Knight at Brookhaven Laboratory, William C. Dickinson of the MIT Research Laboratory of Electronics, and Warren Proctor and Fu Chun Yu in Bloch’s group at Stanford—directed Gutowsky’s research in an unexpected and very fruitful direction: NMR studies of molecules in liquids. The discovery of the chemical shift threatened to disturb the precision measurements of nuclear moments underway in several physics laboratories because it demonstrated that the resonance frequencies of the nuclei under scrutiny depended on the electronic environment of the atoms in the molecule. For the physicists this was an unpleasant surprise. For the chemists it was exactly what they needed to use NMR as a probe for the structures of molecules. It proved to be the beginning of a stellar rise of NMR in organic chemistry and other areas of the chemical sciences and technologies.
Gutowsky, together with his first graduate student, Charles J. Hoffman, extended the validity of the chemical shift measurements by observing the shift with protons. In addition, Gutowsky and Hoffman made suggestions for the refinement of the quantum physical theory of the chemical shift, originally provided by the Harvard physicist Norman Ramsey. In correlating the chemical shift data of fluorine compounds with the electronegativity of the atoms bound to fluorine in the respective molecules, Gutowsky and Hoffman laid the empirical groundwork for an important simplification of Ramsey’s formula, achieved in 1953 by Apollo Saika in Gutowsky’s group and his Illinois colleague, the physicist Charles P. Slichter.
In 1951 Gutowsky and his group embarked on a research project that firmly embedded NMR in one of the most prestigious and progressive areas in chemistry of the time, physical organic chemistry. Meanwhile, a group of three graduate students in the laboratory, David McCall, Bruce McGarvey, and Leon (Lee) H. Meyer, together with
the assistant in electronics, Robert McClure, constituted the group that made decisive observations and interpretations for the foundations of chemical NMR. The first of their joint projects considered the relation of chemical shift data in fluorine-substituted benzene compounds with resonance and inductive effects. The resonance effect explains the variations of the distribution of electrons in molecules by means of their delocalization; the inductive effect accounts for the ability of the substituents to attract or repel the localized bonding electrons. Both effects were used very successfully for explaining the courses of chemical reactions. In general, Gutowsky speculated about the origins of the chemical shift in terms of bond hybridizations, inspired by the theoretical contributions of Pauling and Mulliken. Moreover, Gutowsky extensively applied the technique of correlation analysis, following the ruling that a linear correlation of two parameters enabled insights into the nature of both. In 1951, and related to such a correlation, Gutowsky defined the chemical shift parameter δ, which is still in use in the early twenty-first century.
Even though by 1952 Gutowsky, his coworkers, and other scientists had successfully established NMR in the fields of chemical physics and physical organic chemistry, the majority of organic chemists working on syntheses were still unaware of the potential of the method. In the course of a study of 220 organic compounds, Meyer, Saika, and Gutowsky recognized that the chemical shift data of protons embedded in functional groups, that is, characteristic atomic groupings in a molecule, were distinctive enough to enable identification of the functional groups. Thus, just as in infrared spectroscopy, NMR could be applied as a fingerprint technique. Also, with regard to the presentation of his results, Gutowsky chose infrared spectroscopy as his model. Figure 1 shows a chart relating the chemical shift data to functional groups. It was designed after the famous Colthup chart that was a standard tool in the interpretation of infrared spectra.
In 1953 the manufacturer of NMR spectrometers, Varian Associates of Palo Alto, California, asked Gutowsky for permission to reprint the chart in its Technical Information Bulletin. Varian Associates, founded in 1948 by the brothers Sigurd and Russell Varian, among others, was closely allied to Stanford’s Department of Physics, where Felix Bloch had coinvented NMR in 1946. Varian Associates had secured the patents of Bloch and employed him as a consultant. Many of Bloch’s coworkers (among them Packard) entered the firm, which was the first company to manufacture NMR spectrometers and until the early 1970s dominated the market. Members of Bloch’s team and scientists of Varian Associates crucially contributed to technical improvements and to scientific breakthroughs, among them the chemical shift and the second chemically relevant phenomenon in NMR, the so-called spin-spin coupling.
Spin-Spin Coupling . In a memorandum for a chemistry course that he held in 1949, Gutowsky noted that “‘errors’ sometimes are more important than preconceptions as to what is to be obtained in a given experiment” (Reinhardt, 2006, p. 71). This is exactly what happened in his own laboratory a year later, when Hoffman and McClure observed unexplainable double resonance lines during experiments with phosphorustrifluoride. At first they regarded the phenomenon as accidental, due to an impurity. Later they simply set it aside as an anomaly. Gutowsky did not become aware that this could be a new effect until Proctor and Yu of Bloch’s group reported multiplets that were inexplicable by the chemical shift alone. He assigned McCall to undertake an experimental characterization with pure compounds containing different numbers of phosphorus and fluorine atoms. Soon it became clear that the effect was associated with the nuclear magnetic moments, though it was not caused by an already-known mechanism. At the same time, observations of Erwin L. Hahn, employing his spin-echo NMR method while he was still at the Department of Physics at the University of Illinois at Urbana, led to similar conclusions. In due course four teams—Gutowsky’s and Slichter’s at Urbana and Packard’s and Hahn’s at Stanford (Hahn being then in Bloch’s unit)—in close cooperation established the spin-spin coupling constant as a novel parameter in NMR. The accepted theoretical interpretation, however, originated with Ramsey and Purcell at Harvard, who attributed the splitting of the spectral lines to a coupling mechanism of the nuclei via the spins of the bonding electrons. Characteristically, as had been the case with the chemical shift, Gutowsky’s description of the new effect explicitly included its use as a means for unraveling molecular structure, while Ramsey’s more exact and refined treatment did not account for this possibility.
In the following decades, spin-spin couplings opened several avenues for the study of molecular structure. With refined equipment, couplings between nuclei separated by several bonds could be measured, and it became possible to detect their relative orientation in space. While at the University of Illinois in the late 1950s, and partially in cooperation with members of Gutowsky’s group, Martin Karplus set up a mathematical equation that related the dihedral angle between bonds to the spin-spin coupling constants measured. In Gutowsky’s group, Cynthia Jameson later on decisively contributed to this topic. This work was the basis for using NMR in the unraveling of the stereochemistry of molecules. In general, however, the exact assignment of the peaks—considerably complicated by the overlay of chemical shifts and spin-spin couplings in the spectrum of a large molecule—could be a time-consuming endeavor, and several partially computer-based interpretational methods were developed for this purpose. Gutowsky contributed here, making use of the available computing power of the ILLIAC, an early supercomputer built at the University of Illinois.
An issue of great concern to the scientists involved in the discovery of the spin-spin coupling was the disappearance of splittings due to various chemical and physical effects. One such effect was chemical exchange, a term that refers here to both exchange of atomic groupings and to internal rotations of the molecules. The first systems that Gutowsky investigated in this area were acids in aqueous solutions. By observing the concentration-dependence of the proton chemical shift between the water molecules, the hydronium ions, and the undissociated acid, Gutowsky and Saika postulated the collapse of the multiplet observed into a single line, when the exchange rate increased. But they could not experimentally verify their hypothesis. Later, Gutowsky ascribed this neglect to the shortage of molecular systems showing an exchange rate at the appropriate time range and to the lack of mathematical sophistication among the chemists who observed such exchanges. Only in 1955, when William D. Phillips of Du Pont reported on restricted rotation of amides, did Gutowsky, with his graduate student, Charles H. Holm, go back to the topic. They examined intramolecular rotational rates and determined the energy barriers between the different conformational forms of the molecules. Their study, although it needed considerable refinement in both theoretical and instrumental respects, opened a whole new area for NMR studies of dynamics of molecules, and it subsequently was often cited. In the 1960s Gutowsky—together with Adam Allerhand—questioned the accuracy of existing methods for studying chemical exchange and made proposals for basing the experimental values on a more secure footing. Although their plea was largely ignored in the chemical community, it was a sign of Gutowsky’s ongoing commitment to improving the methods available to the scientific community and an example of his quest for experimental rigor.
Until the late 1960s, Gutowsky’s research program comprised all important areas of NMR and also occasionally included the related technique of electron spin resonance. The program’s aim was to obtain insights into the complex phenomenology of NMR spectra through the development of novel methods that could be of use in chemistry. Its range stretched from theoretical aspects to applications in organic chemistry and biochemistry. Its core was the experimental approach of molecular spectroscopy using self-built instrumentation. In the 1960s Gutowsky’s contributions tended to be pushed aside by the waves of organic chemists entering the field with commercially available instruments. An equally important cause for his diminished activity was the administrative roles that he pursued. In the 1970s, a collaboration with his Illinois colleague, Eric Oldfield, enabled Gutowsky to contribute to recent NMR applications in biochemical research, although even then most of his time was consumed by managerial duties.
Administrative Work . For Gutowsky, career steps closely followed scientific achievements. In 1951, he was promoted to assistant professor; in 1955 he became associate professor and in 1956 full professor of physical chemistry. The latter came with headship of the division of physical chemistry, lasting until 1962. The Department of Chemistry and Chemical Engineering at the University of Illinois was unusual for the times in comprising six divisions: organic chemistry, physical chemistry, inorganic chemistry, analytical chemistry, chemical engineering, and biochemistry. The fact that biochemistry and chemical engineering still belonged to chemistry was attributed in many respects to the strong leadership of Roger Adams, under whom organic chemistry was by far the dominant subdiscipline. When, in 1967, Gutowsky accepted the position of head of the department, he realized that in the long run, this organizational arrangement had to be changed. In 1970 he oversaw the reorganization of the department into a school of chemical sciences with three separate departments. As director of the school and head of chemistry department, Gutowsky until 1983 mainly pursued administrative functions.
In his very first year as department head, Gutowsky faced demonstrations against the presence of Dow Chemical employees on campus. Dow was heavily criticized because of its production of napalm during the Vietnam War, but Gutowsky diplomatically prevented the outbreak of violence. Next to local responsibilities, issues of national importance in the area of education were at the forefront of Gutowsky’s agenda. By the mid-1960s he was a member of the committee that prepared the so-called Westheimer Report on the state of the chemical sciences in the United States, named after the committee chairman, Frank Westheimer. The report was comprehensive, influencing science policy in general and serving as a model for similar reports in the related sciences. In a 1972 letter to the journal Science, Gutowsky challenged the use of quota to improve the access of women to university positions. Characteristically, even regarding societal matters, he used quantitative methods, in this case related to his assumption that a shortage of both highly trained and mobile female scientists existed. He was chairman of the American Chemical Society’s Committee on Professional Training, and in his function as advisor to the National Science Foundation in 1973, he called for a reversal in the U.S. educational system of cutbacks in the 1970s after the major expansion in the 1960s. In times of heightened ecological awareness, his contribution toward dealing with environmental threats was directing a National Research Council study on the impact of halocarbons on the ozone layer. The ecological crisis never lost his attention.
Gutowsky used NMR as a method for the design and control of novel effects, and he was convinced that NMR enabled scientists to understand natural phenomena better. Nevertheless, the enormous resources that a technology-centered society was spending on scientific research caused him to question the future of the scientific enterprise:
One of my pet sayings is that research is over-supported. That it’s a natural resource we are mining, taking it out at such a rage that there won't be any left for our grandchildren. We should leave some natural discoveries for the future. I tried that one on my colleagues at academy meetings designed to get more money out of the government. That was after Frank Westheimer made a pitch for 15 percent increase per year for ever and ever. I was teaching physical chemistry then and I amused myself and the class by computing how long it would be before the national budget would be totally spent. I think more undergraduate students carried away this lesson than anything else I ever taught. (Reinhardt, 2006, p. 82)
In 1983, after his resignation as director, he embarked on a new research field, pulsed microwave spectroscopy. For this, he took over the equipment of his recently deceased colleague, William H. Flygare. At first, Gutowsky regarded this task as a means for enabling Flygare’s students to finish their projects. But pulsed microwave spectroscopy became Gutowsky’s main scientific occupation for more than a decade. His work on weakly bound clusters of atoms and molecules resulted in more than fifty publications, with Tryggvi Emilsson being his most important coworker during this period. Here, he was able to retain his peculiar style of scientific work: investigating the effects of radiation on molecules, undertaken with self-built equipment in a relatively small group. For his NMR work, he received many honors, among them the National Medal of Science in 1976 and the 1984 Wolf Prize in Chemistry.
In 1949 Gutowsky married Barbara J. Stuart, a Radcliffe graduate. They had three children: Daniel K., Robb E., and Christopher C. Gutowsky. Divorced in 1981, the following year he married Virginia A. Warner, a psychologist, elementary school teacher, and violinist. For recreation, Gutowsky loved to work in his rose garden, occasionally breeding new varieties. Although Gutowsky officially retired in 1990, he continued working until the late 1990s. He died of myocardial infarction at Carle Foundation Hospital.
WORKS BY GUTOWSKY
With George B. Kistiakowsky and George E. Pake. “Structural Investigations by Means of Nuclear Magnetism, I. Rigid Crystal Lattices.” Journal of Chemical Physics 17 (1949): 972–981.
With George E. Pake. “Structural Investigations by Means of Nuclear Magnetism, II. Hindered Rotation in Solids.” Journal of Chemical Physics 18 (1950): 162–170.
With Charles J. Hoffman. “Nuclear Magnetic Shielding in Fluorine and Hydrogen Compounds.” Journal of Chemical Physics 19 (1951): 1259–1267.
With David W. McCall. “Nuclear Magnetic Resonance Fine Structure in Liquids.” Physical Review 82 (1951): 748–749.
With David W. McCall and Charles P. Slichter. “Coupling among Nuclear Magnetic Dipoles in Molecules.” Physical Review 84 (1951): 589–590.
With Leon H. Meyer and Apollo Saika. “Electron Distribution in Molecules III. The Proton Magnetic Spectra of Simple Organic Groups.” Journal of the American Chemical Society 75 (1953): 4567–4573.
“Nuclear Magnetic Resonance.” Annual Review of Physical Chemistry 5 (1954): 333–356. A review that covers most of the early NMR work in its scientific context.
With Charles H. Holm. “Rate Processes and Nuclear Magnetic Resonance Spectra II. Hindered Internal Rotation of Amides.” Journal of Chemical Physics 25 (1956): 1228–1234.
With Martin Karplus and David M. Grant. “Angular Dependence of Electron-Coupled Interactions in CH 2 Groups.” Journal of Chemical Physics 31 (1959): 1278–1289.
“Chemical Aspects of Nuclear Magnetic Resonance.” Journal of Magnetic Resonance 17 (1975): 281–294. A historical address on the occasion of receiving the 1974 award of the International Society of Magnetic Resonance.
With Jiri Jonas. “NMR—An Evergreen.” Annual Review of Physical Chemistry 31 (1980): 1–27.
“The Coupling of Chemical and Nuclear Magnetic Phenomena.” In Encyclopedia of Nuclear Magnetic Resonance, edited by David M. Grant and Robin K. Harris. Vol. 1, Historical Perspectives. New York: Wiley, 1996. A historical summary, partially based on Gutowsky’s 1975 article, “Chemical Aspects of Nuclear Magnetic Resonance,” cited above.
Becker, Edwin D., Cherie Fisk, and C. L. Khetrapal. “The Development of NMR.” In Encyclopedia of Nuclear Magnetic Resonance, edited by David M. Grant and Robin K. Harris. Vol. 1, Historical Perspectives. New York: Wiley, 1996. The standard history of NMR.
Jonas, Jiri, and Charles P. Slichter. “Herbert Sander Gutowsky 1919–2000.” National Academy of Sciences Biographical Memoirs 88 (2006): 1–17.
Reinhardt, Carsten. “Chemistry in a Physical Mode: Molecular Spectroscopy and the Emergence of NMR.” Annals of Science 61 (2004): 1–32. Includes an account of Gutowsky’s early work at Harvard.
———. Shifting and Rearranging: Physical Methods and the Transformation of Modern Chemistry. Sagamore Beach, MA: Science History Publications, 2006. Chapter 2 discusses Gutowsky’s major contributions.
Slichter, Charles P. “Some Scientific Contributions of Herbert S. Gutowsky.” Journal of Magnetic Resonance 17 (1975): 274–280.
Zandvoort, Henk. Models of Scientific Development and the Case of Nuclear Magnetic Resonance. Dordrecht, Netherlands: Reidel, 1986. A study of the early history of NMR that is a further development of Imre Lakatos’s approach to the philosophy of science.
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