Dr. Gilles Klopman (February 24, 1933 – January 10, 2015) held the position of Charles F. Mabery Professor of Research in Chemistry; Professor of Oncology and Environmental Health Sciences; and Director of the Laboratory for Decision Support Methodologies at Case Western Reserve University in Cleveland, Ohio. Additionally, he served as an adjunct professor of Environmental and Occupational Health at the University of Pittsburgh.[1]
Dr. Klopman received his education in Belgium and the United States, specializing in theoretical chemistry and physical organic chemistry (L. es Sc., University of Brussels (Belgium), 1956; Dr. es Sc., University of Brussels, 1960; Postdoctoral Fellow, University of Texas, 1965–66).
His notable contributions to the theory of chemical reactivity include the development of the Klopman–Salem equation, first described independently by him and Lionel Salem in 1968. It explains the energetic changes that occur when two chemical species approach each other in the course of a reaction. The Klopman–Salem equation provides a mathematical foundation for key assumptions in frontier molecular orbital theory and HSAB theory.