Dr. Odd Hassel was a distinguished Norwegian chemist born in Kristiania (now Oslo) on May 17, 1897. He commenced his academic journey at the University of Oslo in 1915, where he studied mathematics, physics, and chemistry, graduating with a cand. real. degree in 1920. Following a period of study in France and Italy, he pursued doctoral research in Germany, initially working in Munich before completing his Dr. Phil. at Berlin University in 1924. Hassel returned to his alma mater, the University of Oslo, in 1925, where he served as a universitetsstipendiat and later as a dosent in physical chemistry and electrochemistry. In 1934, he was appointed to the first chair of physical chemistry in Norway, establishing and leading the department of physical chemistry until his retirement in 1964.
Hassel initially focused on inorganic chemistry during his early teaching years at Oslo, but from 1930 onward, his research centered on molecular structure, particularly the conformation of cyclohexane and its derivatives. His groundbreaking work demonstrated that ring-shaped carbon molecules exist in three dimensions rather than on a single plane, challenging the prevailing scientific understanding of the time. By analyzing the number of bonds between carbon and hydrogen atoms, Hassel established the impossibility of these molecules existing in two dimensions, thereby pioneering the field of conformational analysis. This revolutionary approach enabled the prediction of chemical and physical properties of organic molecules based on their three-dimensional atomic configurations. His seminal contributions to understanding molecular geometry earned him the Nobel Prize in Chemistry in 1969, which he shared with Derek Barton for their complementary work in developing conformational analysis.
Hassel's introduction of the concepts of electric dipole moments and electron diffraction significantly advanced the Norwegian scientific community's understanding of molecular structure. His research methodology, particularly the application of the rotating sector method in electron-diffraction studies, provided crucial insights into molecular geometry that continue to inform chemical research today. In recognition of his scientific achievements, Hassel received numerous honors including the Guldberg-Waage Medal and Gunnerus Medal in 1964, honorary degrees from the Universities of Copenhagen and Stockholm, and appointment as a Knight of the Order of St. Olav. He was elected to prestigious academies including the Norwegian Academy of Sciences, the Royal Danish Academy of Sciences, and the Royal Swedish Academy of Sciences. Hassel's enduring legacy as a pioneer in physical chemistry remains foundational to modern understanding of molecular structure and its relationship to chemical properties.
