Karl Herzfeld

Karl Ferdinand Herzfeld (February 24, 1892 – June 3, 1978) was an Austrian–American physicist and chemist. He worked on condensed matter physics, fluid dynamics, reaction rate theory, and statistical mechanics. In seminal 1919 and 1921 papers, he derived the rate equation for unimolecular reactions and proposed the Lindemann mechanism of third-body deactivation in unimolecular reactions. In 1927, he was the first to quantify when a substance is a metal or an insulator. The Goldhammer–Herzfeld criterion to classify metalloids is named after him. Herzfeld and Frank O. Rice developed the theory of translational-vibrational energy transfer, and proposed the radical mechanism for pyrolysis in 1934, known as the Rice–Herzfeld mechanism.

Herzfeld also wrote on philosophy and theology. He was married to anthropologist Regina Flannery.

Education Karl Ferdinand Herzfeld was born on February 24, 1892, in Vienna, into a "prominent, recently assimilated Jewish family". His father was Professor Ordinarius of Obstetrics and Gynecology at the University of Vienna. His mother, Camilla Herzog, was the daughter of a newspaper publisher and sister of the organic chemist R. O. Herzog.

Herzfeld's thesis applied statistical mechanics to a gas of free electrons as a model for a theory of metals. By the time he received his doctorate, he already had published six scientific papers. In one of them, he attempted to derive a model of the hydrogen atom. This paper was published in 1912, shortly before Niels Bohr submitted his first paper on the Bohr model of the hydrogen atom.

Upon receipt of his doctorate, Herzfeld volunteered for service in the Austro-Hungarian Army. World War I broke out shortly thereafter and he served until 1918, rising to the rank of first lieutenant. Herzfeld's thesis advisor Hasenöhrl was called to serve during World War I and was killed at the front. 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. who was professor ordinarius of 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 professor extraordinarius 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. was the first to correctly analyze translation-vibration energy transfer in molecular gases, later extended to liquids, as reviewed by Karen Johnson in her extensively referenced biographical article. 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 in turn advised Richard Feynman, obtained his PhD under the guidance of Herzfeld in 1933. One of his doctoral students at Catholic was Virginia Griffing, the first woman on the faculty of the university's physics department.

In 1959, Herzfeld and Theodore A. Litovitz collaborated on a book, in part, summarizing Herzfeld's thinking on ultrasonics over the 30 plus years since his article with F. O. Rice. In 1966, Herzfeld published a review article summarizing 50 years of developments in physical ultrasonics.

Personal life 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.

Honors 1958 – Elected to the American Academy of Arts and Sciences 1960 – Elected to the National Academy of Sciences 1964 – US Navy's Meritorious Service Citation for his services during World War II

Publications Articles

[Herzfeld's doctoral dissertation at Vienna University under the direction of Professor Friedrich Hasenöhrl]

Karl F. Herzfeld Fifty Years of Physical Ultrasonics, The Journal of the Acoustical Society of America Volume 39, Issue 5A, pp. 813–825, The Catholic University of America, Washington, D. C. (Received 27 July 1965)

Books Karl F. Herzfeld Zur Elektronentheorie der Metalle (Barth, 1913) Karl F. Herzfeld Physikalische und Elektrochemie In Encyklopädie der Mathematischen Wissenschften mit Einschluss ihrer Anwendungen Band V, Heft 6, pp. 947–1112 (Leipzig: B. G. Teubner, 1921) Karl F. Herzfeld Grösse und Bau der Moleküle In Handbuch der Physik 1st ed., band 22, ed. A. Smekal, pp. 386–519 (Berlin: Springer-Verlag, 1924) (second ed., band 24, 1933, pp. 1–252). Karl F. Herzrfeld, Kinetische Theorie der Wärme In Müller-Pouillets Lehrbuch der Physik Band 3 (Braunsweig: F. Viewig und Sohn, 1925) Karl F. Herzfeld Klassische Thermodynamik In Handbuch der Physik 1st ed., Band 9, pp. 1–140 (Berlin, Springer-Verlag, 1926) Karl F. Herzfeld and K. L. Wolf Absorption und dispersion In Handbuch der Physik 1st ed., Band 20, pp. 480–634 (Berlin: Springer-Verlag, 1928) Karl F. Herzfeld Gittertheorie der festen Körper In Handbuch der Experimental Physik Band 7, eds. W. Wien and F. Harms, pp. 325–422 (Leipzig: Akademische Verlagsgesellschaft, 1928) Karl F. Herzfeld and H. M. Smallwood The kinetic theory of gases and liquids In A Treatise on Physical Chemistry 2nd ed., vol. 1, ed. H. S. Taylor, pp. 73–217 (New York: Van Nostrand, 1931) Karl F. Herzfeld and H. M. Smallwood Imperfect gases and the liquid state In A Treatise on Physical Chemistry 2nd ed., vol. 1, ed. H. S. Taylor, pp. 219–250 (New York: Van Nostrand, 1931) Karl F. Herzfeld Relaxation phenomena in gases In Thermodynamics and Physics of Matter vol. 1, ed. F. Rossini, pp. 646–735 (Princeton, N.J.: Princeton University Press, 1955) Karl F. Herzfeld and V. Griffing Fundamental physics of gases In Thermodynamics and Physics of Matter vol. 1, ed. F. Rossini, pp. 111–176 (Princeton, N.J.: Princeton University Press, 1955) Karl F. Herzfeld and Theodore A. Litovitz Absorption and Dispersion of Ultrasonic Waves. Pure and Applied Physics Volume 7, (Academic Press, 1959) Karl F. Herzfeld Fundamental Physics of Gases (Princeton University Press, 1961) Karl F. Herzfeld Questions in Statistical Mechanics: Some Reactionary Viewpoints by Karl F Herzfeld (Center for Theoretical Studies, University of Miami, 1971)