W. Carl Lineberger, JILA Fellow and E. U. Condon Distinguished Professor of Chemistry and Biochemistry at the University of Colorado, Boulder, has won the 2015 NAS Award in Chemical Sciences. He was recognized for the development of negative ion photoelectron spectroscopy, which scientists can use to determine the electron affinity of the neutral version of an atom or molecule. Electron affinity—the change in energy that occurs when an electron is added to an atom or molecule—provides important information about atoms and molecules and how they interact in chemical reactions. The “periodic table” of atomic electronic affinities now included in general chemistry textbooks is founded on Lineberger’s early work with negative-ion photoelectron spectroscopy. His development of anion photoelectron spectroscopy as a tool to study small molecules has provided an important method to characterize highly reactive, short-lived species known as free radicals. This tool has also provided a new, direct way to observe the structure and evolution of molecules in the process of undergoing a chemical reaction. Lineberger’s experimental methods are now in widespread use in laboratories throughout the world.
The NAS Award in Chemical Sciences was first awarded in 1979 to Linus Pauling for his studies, which elucidated the properties of stable molecules of progressively higher significance to the chemical, geological, and biological sciences. The NAS Award in Chemical Sciences award has recognized some of the nation's greatest chemists. In the past few decade, 14 recipients have been honored with a National Medal of Science, and six recipients have received a Nobel Prize in Chemistry (Taube 1983; Hoffmann 1981; Brown 1979; Cram 1987; Zewail 1999; Sharpless 2001).