Weitao Yang is the 26-27 Joseph O. Hirschfelder Awardee
Prof. Weitao Yang, a pioneering contributor to theoretical and computational quantum chemistry, specifically in Density Functional Theory (DFT) development and electronic structure calculations, has been awarded the 2026–2027 Joseph O. Hirschfelder Prize in Theoretical Chemistry, presented by the Theoretical Chemistry Institute at the University of Wisconsin–Madison.
Professor Yang will visit the University of Wisconsin–Madison in November to present two scientific lectures and will be honored at the Joseph O. Hirschfelder Prize in Theoretical Chemistry banquet.
As one of the world’s leading theoretical chemists, Prof. Yang’s research has transformed how scientists use quantum mechanics to understand and predict the properties and behavior of molecules. While his Lee–Yang–Parr (LYP) correlation functional, a key component of the widely used B3LYP functional, is among his best-known contributions, his impact extends far beyond this work. He established fundamental connections between electronic structure and chemical reactivity, and exposed key limitations of approximate density functionals through his work on fractional electrons and fractional spins. He pioneered the divide-and-conquer approach for large molecular systems, advanced QM/MM methods for studying chemical reactions in complex environments such as enzymes, and developed the widely used noncovalent interaction (NCI) approach for visualizing weak interactions. Together, these contributions have advanced our understanding of chemical bonding, reactivity, charge transfer, and noncovalent interactions while making quantum-mechanical calculations practical for increasingly large and complex systems.
The annual Joseph O. Hirschfelder Prize in Theoretical Chemistry was established by the Theoretical Chemistry Institute in 1991 from funds donated by Professor Joseph O. Hirschfelder and his wife, Dr. Elizabeth S. Hirschfelder. The prize, awarded by the UW–Madison Department of Chemistry, recognizes scientists who have made outstanding contributions to theoretical chemistry. Each recipient visits UW–Madison to present two lectures, meet with faculty and graduate students, and receive the award, which includes a monetary prize.