Biography of Herbert Aaron Hauptman (1917-2011)

American scientist born in New York on February 14, 1917 and died in Buffalo on October 23, 2011. In 1985 he/she was awarded the Nobel Prize in chemistry, jointly with Jerome Karle, for their outstanding contributions to the development of direct methods. This methodology allows to infer the spatial location of the atoms of the chemical compounds using the position and intensity of the reflections that are obtained when the x-rays diffract through the windows.

His interest in mathematics and the sciences most started as soon as he/she learned to read and remained throughout his life. He/She graduated in mathematics in 1937 by the City University of New York and the master in mathematics at Columbia University (1939). He/She married Edith Citrynell in 1940, but their two daughters were not born until after the second world war.

After the war, he/she decided to make a doctorate and pursue a career in basic scientific research. With this purpose began to collaborate with Jerome Karle at the laboratory of Naval Research in Washington, D.C. (1947) and at the same time entered the doctoral program in the University of Maryland. His collaboration with Karle was very fruitful to complement his training in mathematics with the Chemical Physics of Karle. An algorithm of Euclidean N-Dimensional received his doctorate in 1955 with a thesis. However, his monograph of 1953, entitled solution of the problem of phase I. Crystal Centrosimetrico, already contained the basics of direct methods in x-ray crystallography. The most important idea was the introduction of probabilistic methods, especially the distribution of combined probability of several factors of structure as the main tool for the determination of the phase. In that monograph also introduced the concepts of invariants and semiinvariantes of structure (Special linear combinations of the phases) and their use to devise formulas that specify the origin of all space groups centrosimetricos. The extension to space groups not centrosimetricos was carried out a few years later. The notion of the invariants and semiinvariantes of structure proved to be of great importance since it was also used to relate the observed intensities of diffraction with the phases of the factors structure.

In 1970 he/she joined the Group of crystallography of the medical foundation of Buffalo (which was later renamed Institute of research medical Hauptman-Woodward) and two years later he/she replaced Dorita Norton as director of research. Its director's work he/she combined it with his post of Professor of investigation of the Department of biophysical Sciences and an associate professor in the computer science Department at the State University of New York. In the first years he/she formulated the principle of neighbourliness and the concept of extension. In the 1980s, he/she began work on the problem of the combination of traditional techniques of direct methods with isomorphic substitution and anomalous dispersion to facilitate resolution of crystal structures of macromolecules. He/She later formulated the problem of phase in the x-ray crystallography as a minimum principle for the purpose of strengthening techniques by existing direct methods.

Hauptman received honorary degrees from universities in the United States.USA, Italy, Israel, Poland and Canada. He/She was elected member of the National Academy of Sciences (1988). Among the numerous awards he/she obtained (apart from the Nobel Prize) include the Schoellkopf Award (1986).

He was President of the philosophical society of Washington (1969-1970) and the Association of institutes of independent research (1979-1980).