[3] In 1902, when Herzfeld was 10 years old, he was enrolled in the private Gymnasium Schottengymnasium, which was run by the Benedictine Order of the Roman Catholic Church and had its name derived from the fact that the founders came from Scotland.

In 1913, he went to study at the University of Göttingen, after which Herzfeld returned to Vienna, and was granted his doctorate in 1914, under Friedrich Hasenöhrl, who had become director of the Institute for Theoretical Physics, upon the suicide of Ludwig Boltzmann in 1906.

[3][4] Herzfeld's doctoral thesis applied statistical mechanics to a gas of free electrons as a model for a theory of metals.

Herzfeld's thesis advisor Hasenöhrl was called to serve during World War I and was killed at the front.

[7] During his tenure in the military, Herzfeld published six papers on statistical mechanics applied to problems in physics and chemistry, especially to the structure of matter – gases, liquids, and solids.

First, he was an assistant at the physico-chemical laboratory of Kasimir Fajans at Ludwig Maximilian University of Munich (LMU).

In 1925, Herzfeld published his book on kinetic theory and statistical mechanics,[9] which became a graduate-level textbook in German-speaking universities.

[3] 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.

Their 1928 paper[10] considered the role of molecular vibrations in the transfer of energy between ultrasonic waves and gas molecules.

A. Bearden, another experimentalist, thought there was too much emphasis on theoretical physics and the number of German physicists in the small department was out of balance.

Finally too, Bearden thought Herzfeld had caused dissension in the department over his strong support to promote Göppert-Mayer from research associate in physics to a regular faculty appointment.

Herzfeld's teaching responsibilities and salary at Catholic University were about the same as that at Johns Hopkins, but there were additional administrative duties, as he was also chairman of the physics department.

[19] In 1938, Herzfeld married Regina Flannery, who was an instructor of anthropology at Catholic University; by the time she retired in 1970, she had risen to professor and the first woman to head that department.