General view of an apparatus used to study the structure of molecules by means of the Raman effect using a three-glass prism Steinheil Spectrograph. This apparatus was used at the U.S. Department of Agriculture's Fixed Nitrogen Research Laboratory located in Washington, D.C. Named for Sir C.V. Raman, Raman spectroscopy is a spectroscopic technique used to observe vibrational, rotational, and other low-frequency modes in a system. In chemistry, it is commonly used to provide a so-called fingerprint by which molecules can be identified.

The Fixed Nitrogen Research Laboratory (F.N.R.L.) was established at American University in 1919 under the directorship of Arthur B. Lamb. Initially part of the War Department, the F.N.R.L. was the successor to several wartime initiatives to develop a secure domestic supply of nitrate compounds necessary for the manufacture of explosives during World War I. With a staff of about 110 individuals, including 35 to 50 chemists, the F.N.R.L. focused on the manufacture, production, and development of products of atmospheric nitrogen, including munitions and fertilizers.