[5] El-Sayed earned his doctoral degree in chemistry from Florida State University working with Michael Kasha, the last student of the legendary G. N.

In 1994, he retired from UCLA and accepted the position of Julius Brown Chair and Regents Professor of Chemistry and Biochemistry at the Georgia Institute of Technology.

[6][7] El-Sayed's research interests include the use of steady-state and ultra fast laser spectroscopy to understand relaxation, transport and conversion of energy in molecules, in solids, in photosynthetic systems, semiconductor quantum dots and metal nanostructures.

A major focus of his lab is currently on the optical and chemical properties of noble metal nanoparticles and their applications in nanocatalysis, nanophotonics and nanomedicine.

[8] For his work in the area of applying laser spectroscopic techniques to study of properties and behavior on the nanoscale, El-Sayed was elected to the National Academy of Sciences in 1980.

Mostafa El-Sayed was awarded the 2007 US National Medal of Science "for his seminal and creative contributions to our understanding of the electronic and optical properties of nanomaterials and to their applications in nanocatalysis and nanomedicine, for his humanitarian efforts of exchange among countries and for his role in developing the scientific leadership of tomorrow.

[10] Professor El-Sayed also received the 2016 Priestley Medal, the American Chemical Society’s highest honor, for his decades-long contributions to chemistry.

[11] The rate of intersystem crossing is relatively large if the radiationless transition involves a change of orbital type.This rule pertains to phosphorescence and similar phenomena.