Learn More About Physics

Egyptian American chemist Ahmed Zewail won the 1999 Nobel Prize in chemistry for his work in studying chemical reactions. Zewail
Ahmed H. Zewail, born in 1946, Egyptian American chemist and Nobel Prize winner. Zewail received the 1999 Nobel Prize in chemistry for developing a way to study chemical reactions in slow motion using ultra-short laser flashes. The Royal Swedish Academy of Sciences, which awards the Nobel Prize, said that his contributions have revolutionized chemistry, because this method of investigation enables chemists to understand and predict the nature of chemical reactions.
Zewail was born in Alexandria, Egypt. He received his bachelor's and master's degrees from the University of Alexandria. He moved to the United States and, in 1974, earned his Ph.D. degree from the University of Pennsylvania in Philadelphia. After completing his Ph.D., he went to the University of California at Berkeley as a research fellow. In 1976 Zewail joined the faculty at the California Institute of Technology (Caltech) in Pasadena, and in 1982 he became a full professor. In 1990 he became the first person to hold the Linus Pauling Chair of Chemical Physics at Caltech.
In a series of experiments he performed during the 1980s, Zewail developed what many have described as the world's fastest camera. This device uses flashes of laser light of such short duration that they “freeze” the moment when atoms and molecules come together to form new compounds. Using his laser technique, Zewail was the first person to find out how long it takes for atoms and molecules to form and to break chemical bonds. Using this ability, he has studied a variety of chemical processes, ranging from reactions in Earth’s atmosphere to biological reactions between genetic components within hemoglobin (a compound in red blood cells).
Zewail’s technique uses flashes of laser light that last for a few femtoseconds. One femtosecond equals one millionth of one billionth of a second (0.000000000000001 second). Femtochemisty is the area of physical chemistry that addresses the short time period in which chemical reactions take place and investigates why some reactions occur but not others. Zewail’s picture-taking technique made possible these investigations. One of the first major discoveries of femtochemistry was that intermediate products that form during chemical reactions differ from the starting and end products. By understanding these molecular dynamics, chemists one day may be able to better control chemical reactions and create new molecules.
Zewail has received numerous awards in addition to the Nobel Prize. In 1998 the government of Egypt issued a postage stamp bearing his portrait.