This Month in Physics History

Elmer Samuel Imes, the second black Ph.D. physicist in the United States, and the first to do significant research work, published his first paper in November 1919. The work provided the first accurate determination of the distances between atoms in molecules, expanded the range of applicability of quantum theory, and provided evidence for the existence of two isotopes of chlorine. His research was cited many times and was soon incorporated into textbooks.

Elmer Imes was born in October 1883 in Memphis, Tennessee, the son of missionaries. He attended elementary school in Ohio and high school in Normal, Alabama. He received a bachelor’s degree in science in 1903 from Fisk University, a predominately black university in Nashville, Tennessee.

After receiving his degree, Imes taught physics and math at the Albany Normal Institute in Albany, Georgia. Around 1910, he returned to Fisk, where he continued his own studies in physics and served as an instructor of math and science. He completed his master’s degree in 1915. Fisk didn’t offer any higher degree, so he transferred to the University of Michigan to complete his Ph.D.

At the University of Michigan, Imes worked in the laboratory of his advisor Harrison Randall, designing and building high-resolution infrared spectrometers and detectors.

Imes earned his Ph.D. in physics in 1918, becoming the second African American to earn a Ph.D. in physics, more than 40 years after Edward Bouchet received his Ph.D. from Yale.

Imes’ thesis work involved infrared spectroscopy of diatomic gases HCl, HBr and HF. His main findings were reported in a paper, “Measurements on the near-infrared absorption of some diatomic gases,” published in November 1919 in the Astrophysical Journal. Imes and Randall followed up with some further details in a paper presented at an American Physical Society meeting in November, and a paper in Physical Review.

His work, one of the first applications of high resolution infrared spectroscopy, provided the first detailed spectra of simple molecules, and opened up the field of studying molecular structure through infrared spectroscopy. Imes analyzed hydrogen bromide (HBr), hydrogen chloride (HCl), and hydrogen fluoride (HF). The work presented the first accurate measurement of the distance between atoms in molecules.

The research also provided a verification of quantum theory. Before Imes’ study, some scientists were not certain whether quantum theory applied to the emission spectra of molecules. Imes’ work showed that quantum theory could be applied to the rotational energy states of molecules as well as the vibrational and electronic energy levels.

In 1919, about a year after completing his Ph.D., Imes married Nella Larson, a well-known poet of the Harlem renaissance. The couple lived in New York and became part of the Harlem intellectual society. He came into contact with prominent African American intellectuals including W.E.B Du Bois and Langston Hughes.

Imes’ research was recognized as important by colleagues, and was frequently cited, but the only faculty positions open to Imes were at black colleges and universities, which didn’t have graduate programs.

So after receiving his Ph.D., Imes left academia to work in industry in the New York region. He worked as a research physicist at Federal Engineers Development Corporation for a few years, then at Burrows Magnetic Equipment Corporation, and then as an engineer at the E. A. Everett Signal Supplies.

During that time his work resulted in four patents for instruments for measuring magnetic and electric properties of materials.

Imes found few opportunities to advance in industry, and in 1930, after a decade in industry, he returned to Fisk University.

At Fisk, Imes served as the chair of the physics department. He revised the undergraduate programs and planned a graduate program in physics.

Although he didn’t publish any more of his own papers, Imes did remain active in the research community. He corresponded frequently with other researchers and equipment designers and continued some of his own work in infrared spectroscopy.

Imes was dedicated to training students, and conducted research with his students at Fisk. Students in his research lab used x-rays and magnetic techniques to study properties of various materials. He sent some of his students to work at the University of Michigan in the summers to learn x-ray techniques. His research lab was described as “a mecca for those who sought an atmosphere of calm and contentment,” by W.F.G Swann in an obituary.

Believing that students should be exposed to the history of science, Imes also developed a course called “cultural physics,” and wrote a book-length treatise covering the history of science from the Greeks through the early twentieth century.

While on the faculty at Fisk, Imes became involved in a scandal involving a relationship with a white administrator, which, along with other troubles, led to his divorce from Nella Larson. He also experienced financial difficulties from which he never fully recovered. By the late 1930s, his health was declining. He returned to New York, where he died in September 1941.

Throughout his career, Imes was an active member of APS, as well as several other scientific societies.

Reference:  Mickens, Ronald. “Elmer Samuel Imes–Scientist, Inventor, Teacher, Scholar.” In Edward Bouchet—the First African American Doctorate, World Scientific Publishing Company (2002).