John J. Rehr is an American theoretical physicist, professor emeritus of physics at the University of Washington in Seattle.
He then held a NATO postdoctoral fellowship at King's College London and at University of California, San Diego, with Walter Kohn.
[8][9] One of Rehr's major accomplishment was the theoretical solution of the EXAFS problem,[10][11] and quantitative theories of core-level x-ray and electron spectroscopies.
Rehr is also the founding father of the first principles code FEFF8 and the principal investigator of the FEFF project.
His research is supported by the US Department of Energy BES, the DOE Computational Materials and Chemical Sciences Network (CMCSN)[15] Rehr received the Arthur H. Compton Award[16] in 2011 and the International XAFS Society's Achievement Award in 2006.