in 1919, with the intent of studying analytical chemistry and getting a job in the German chemical industry, which had a highly respected reputation. First, he was an assistant at the physico-chemical laboratory of Kasimir Fajans at Ludwig Maximilian University of Munich (LMU). However, once there, he found the challenge of theoretical physics more to his liking. He became Privatdozent for theoretical physics and physical chemistry at LMU, and therefore was much more associated with Arnold Sommerfeld, who was ordinarius professor for theoretical physics and Director of the Institute for Theoretical Physics – a prominent organization for the study of atomic and molecular structure. From 1925, until he left LMU in 1926, he was extraordinarius professor of theoretical physics. During this time, Linus Pauling did postdoctoral studies with him, and he was the thesis advisor for Walter Heitler, who got his doctorate in 1926. In 1925, Herzfeld published his book on kinetic theory and statistical mechanics, which became a graduate-level textbook in German-speaking universities. Career It was in 1926 that Herzfeld took a visiting professorship at the Johns Hopkins University in Baltimore, Maryland, which developed into a regular faculty position. During 1930 and 1932, he was a lecturer at Cooper Union and Fordham University in New York City. While at Johns Hopkins, Herzfeld did considerable research with the chemist Francis O. Rice, who joined the University as an associate professor the same year Herzfeld arrived. Their 1928 paper considered the role of molecular vibrations in the transfer of energy between ultrasonic waves and gas molecules. At Johns Hopkins, Herzfeld worked with other European colleagues on the University's physics faculty, namely James Franck and Maria Goeppert-Mayer, who were awarded Nobel Prizes in Physics in 1925 and 1963, respectively. Franck came to Johns Hopkins after he left Germany in 1933, where he had been ordinarius professor of experimental physics and Director of the Second Institute for Experimental Physics at the University of Göttingen and a close colleague of Max Born, who was Director of the Institute of Theoretical Physics at Göttingen. Goeppert-Mayer was a student of Born, and she joined the Johns Hopkins faculty in 1931. Goeppert-Mayer and Herzfeld published articles on states of aggregation and nuclear fusion reactions. Herzfeld coauthored articles with Franck on photosynthesis, one being after they had both left Johns Hopkins. John Archibald Wheeler, who became a prominent physicist, took his PhD under Herzfeld in 1933. In 1936,