On a visit to the University of Manchester, Joel Hildebrand, the director of UC Radiation Laboratory, invited Calvin to join the faculty at the University of California, Berkeley. This made him the first non-Berkeley graduate hired by the chemistry department in +25 years. He invited Calvin to push forward in radioactive carbon research because “now was the time”. Calvin’s original research at UC Berkeley was based on the discoveries of Martin Kamen and Sam Ruben in long-lived radioactive carbon-14 in 1940.

In 1947, he was promoted to a Professor of Chemistry and the director of the Bio-Organic Chemistry group in the Lawrence Radiation Laboratory. The team he formed included: Andrew Benson, James A. Bassham, and several others. Andrew Benson was tasked with setting up the photosynthesis laboratory. The purpose of this lab was to discover the path of carbon fixation through the process of photosynthesis. The greatest impact of the research was discovering the way that light energy converts into chemical energy. Using the carbon-14 isotope as a tracer, Calvin, Andrew Benson and James Bassham mapped the complete route that carbon travels through a plant during photosynthesis, starting from its absorption as atmospheric carbon dioxide to its conversion into carbohydrates and other organic compounds. The process is part of the photosynthesis cycle. It was given the name the Calvin–Benson–Bassham Cycle, named for the work of Melvin Calvin, Andrew Benson, and James Bassham. There were many people who contributed to this discovery but ultimately Melvin Calvin led the charge.

National Academies Press Biographical Memoir

Awards

1957 Seaborg Award: Melvin Calvin