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Herbert A. Hauptman

October 26, 2011

Most of my readers have surely seen the X-ray diffraction image of a DNA crystal by Rosalind Franklin that enabled James Watson and Francis Crick to decide on a proper structure for DNA. There's not much in that image, except the idea that DNA is a helix. That information enabled Watson and Crick to make some guesses about the DNA structure using the constraints imposed by bond length between atoms.

If the structure of DNA had not been as simple as it is, such X-ray analysis and model-building would not have sufficed. Of course, this is likely the most fundamental tail-wagging-the-dog example there is, since we wouldn't be here if DNA wasn't that simple.

The limitation of Franklin's X-ray photographs is that they conveyed information about X-ray intensity, only. The diffraction intensity depends on electron density, so the X-ray diffraction patten does give some information about how atoms are arranged in a crystal. For simple structures, such as NaCl, that's all you need to determine the structure of the underlying molecule that makes up the crystal.

When your object of study is a macromolecule, intensity information alone can't give you the precise location of atoms. If, however, you have both the intensity and phase of the diffracted radiation, a precise reconstruction is possible. An example of the importance of phase information would be holography. A hologram captures both intensity and phase, so you're able to see a three-dimensional shape. A photograph captures just intensity information, so all you get is a flat image.

If you can acquire both intensity and phase information in X-ray diffraction of a crystal, a little mathematics will allow construction of the electron density of the molecule. This concept, known as the phase problem in the early years of X-ray crystallography, involves a manipulation of Fourier series expansions that is practical only today with the ubiquity of computers.

Herbert A. Hauptman, along with Jerome Karle, developed what's known as the direct method for estimating phase from intensity. That method is a statistical method based on the idea that atoms are roughly point-like, which limits the possible values of intensity and phase because the computed electron density must always be a positive value. The direct method allowed structure determination of molecules of up to about a hundred atoms.

Hauptman, who died on October 23, 2011, at age 94, shared the 1985 Nobel Prize in Chemistry with his collaborator, Jerome Karle, "for their outstanding achievements in developing direct methods for the determination of crystal structures."[1]

Herbert A. HauptmanHerbert Hauptman in 2009, on the occasion of his receiving an honorary degree from the University at Buffalo.

(Photo by Dave Pape via Wikimedia Commons).

I've written often that the partitioning of science and technology into separate fields is arbitrary. Most of us work outside our formal field with good results. Hauptman, who won the Nobel Prize in Chemistry, was a mathematician. As he wrote in his autobiographical note on the occasion of his winning the Nobel prize, he became interested in mathematics as soon as he learned to read.[2] He was awarded a B.S. in mathematics from the City College of New York (CCNY) in 1937, and an M.A. degree in mathematics from Columbia University in 1939.[2]

After World War II, in which he served as a naval officer in the Pacific after being drafted in 1943, Hauptman joined the Naval Research Laboratory (NRL, Washington, D.C.).[3] It was at NRL that he collaborated with physical chemist, Jerome Karle, a former CCNY classmate, while working for his Ph.D. at the University of Maryland. His dissertation topic, "An N-Dimensional Euclidean Algorithm," was a spin-off of his NRL research on the phase problem.[2,4] He was awarded his Ph.D. in Mathematics from the University of Maryland in 1955.

The paper that established Hauptman and Karle's priority was published as a monograph by the American Crystallographic Association in 1953.[5] A technical summary of the method can be found in the introduction in Ref. 6. As is common in a pardigm shift, their approach was controversial and was ignored by chemists.[4] As computers became ubiquitous, and canned software became available, it became more accepted.

Hauptman, as reported in the Los Angeles Times, commented about the phase problem in a 2008 documentary by public television station, WNED-TV, Buffalo,[4]
"All I had to hear was here was a problem that no one could solve. Not even that, but was even impossible to solve on principle,... Once I heard that, there was no letting go."

Hauptman reportedly had developed an aversion to military research, so he left NRL in 1970 to head biophysics research at the Medical Foundation of Buffalo. He remained in Buffalo for the rest of his life, the institute was later renamed the Hauptman-Woodward Medical Research Institute in honor of Hauptman and a major donor, and he served as its president.[3-4] George T. DeTitta, a former executive director of the institute, commented that "If you worked at the institute, you got to know Herb. He was friendly to everyone from the janitors to the top researchers."[3]

Hauptman was honored with honorary degrees from the University of Maryland, 1985; CCNY, 1986; University of Parma, Italy, 1989; Bar-Ilan University, Israel, 1990; Columbia University, 1990; and the State University of New York at Buffalo, 2009, among others. He received the 1984 Patterson Award of the American Crystallography Association in 1984 with Jerome Karle, and he was elected to the U.S. National Academy of Sciences in 1988. [2,7] One interesting fact is that he was Chairman of the Board of Directors of the New York State Institute on Superconductivity.[7]

Hauptman enjoyed playing the violin, and he made mathematical sculptures using stained glass.[4] A photograph of Hauptman and one of his stained glass creations can be found in Ref. 8. He also authored an autobiography in 2008, "On the Beauty of Science -- A Nobel Laureate Reflects on the Universe, God and the Nature of Discovery."[9]

References:

  1. Nobel Prize Web Site, "The Nobel Prize in Chemistry 1985 - Herbert A. Hauptman, Jerome Karle".
  2. Nobel Prize Web Site, Herbert A. Hauptman Autobiography.
  3. Dan Herbeck, "Dr. Herbert Hauptman, Nobel Prize winner, is dead at 94," Buffalo News, October 24, 2011.
  4. Herbert Hauptman dies at 94; won Nobel Prize in chemistry, LA Times, October 25, 2011.
  5. H. Hauptman and J. Karle, "Solution of the Phase Problem. I. The Centrosymmetric Crystal," Acta Crystallographica Am. Monograph No. 3, American Crystallographic Association, 1953 (via Amazon).
  6. Hongliang Xu and Herbert A. Hauptman, "Statistical approach to the phase problem," Acta Crystallographica Section A (Foundations of Crystallography), vol. A60 (2004), pp. 153-157.
  7. Herbert A. Hauptman Personal Web Page, University of Buffalo.
  8. Tom Buckham, "Birthday finds Hauptman embarking on new research," Buffalo News, February 14, 2007 (via the Math News Archive).
  9. Herbert A. Hauptman, "On the Beauty of Science: A Nobel Laureate Reflects on the Universe, God, and the Nature of Discovery," (Edited by D. J. Grothe), Prometheus Books, January 31, 2008, 235 pages (via Amazon).