Mahan was hired as an instructor in the department of chemistry at the
University of California at Berkeley in 1956 and he remained there throughout his career. In 1959 he was an assistant professor and became department chair in 1968. Mahan's research was in the area of gas phase kinetics and photolysis, particularly
gas-phase ion chemistry and
energy transfer.
Yuan T. Lee received his Ph.D. degree in 1965 under his direction and went on to win the Nobel Prize in Chemistry in 1986. He was diagnosed with
amyotrophic lateral sclerosis in 1975 and died October 12, 1982, at the age of 52. ==Textbooks==