Zewail, Ahmed Hassan

Zewail, Ahmed Hassan,

1946–2016, Egyptian-American chemist, b. Damanhur, Egypt, Ph.D. Univ. of Pennsylvania, 1974. He became a U.S. citizen in 1982. A professor at the California Institute of Technology from 1976 until his death, Zewail was awarded the 1999 Nobel Prize in Chemistry for his use of femtosecond spectroscopy to study the transition states of chemical reactions. Using ultrashort laser pulses, he investigated fundamental chemical reactions at the timescale on which they actually occur. His ability to observe the movement of individual atoms in a femtosecond, a millionth of a billionth of a second, brought about a new understanding of the dynamics of matter, with applications ranging from the design of molecular electronic components to the production of new medicines. He also helped develop four-dimensional electron microscopy, in which real-time nanoscale images of a chemical, mechanical, biological, or other process are combined to generate a digital video of that process. Zewail served as a science adviser to President Obama (from 2009) and to the United Nations (from 2013). He also founded what is now the Zewail City of Science and Technology in Cairo, Egypt. Among his books is The 4D Visualization of Matter (2014).