Perhaps the Nobel Prize winner most intimately associated with vacuum studies was Irving Langmuir. Born in 1891 in New York, Langmuir benefited greatly from his close family’s encouragement to observe, analyze and develop questions of all he observed: a sound platform for any scientist. He was schooled in the US and Europe and graduated in 1903 in Metallurgical Engineering. However his developed passion for the study of atoms and molecules (and his recognised abilities) lead him to a different route when he joined Nernst’s laboratory in Göttingen, Germany.
Nernst himself was awarded the Nobel Prize for Chemistry in 1920 and was active in a huge variety of activities. During Langmuir’s time spent in Gottingen, Nernst published in 1905 his most famous contribution: The Nernst Heat Theorem (The Third Law of Thermodynamics). The Theorem says: "The entropy change in a reaction between pure substances approaches zero at T = 0 K." or absolute zero of the (absolute) temperature scale, i.e. zero Kelvin cannot be attained by any mean. One of the most important theorems in science ever offered.
From his focus on atomic and molecular mechanisms Langmuir investigated the properties of adsorbed films and the nature of electric discharges and gases in high vacuum pressures.
In his 1917 paper1 The condensation and evaporation of gas molecules1 he summarized that from ….”a study of chemical reactions in gases at low pressures”….. “it was concluded that in general, when gas molecules strike a surface, the majority of them do not rebound from the surface by elastic collisions, but are held by cohesive forces until they evaporate from the surface….the amount of material absorbed depends on the kinetic equilibrium between the rate of condensation and the rate of evaporation from the surface. Practically every molecule striking the surface condenses (independently of the temperature) and is proportional to the fraction of the surface covered the absorbed material”
This statement had enormous consequences for the understanding of gas-surface interactions which ultimately underpinned the analysis and understanding of the nature of gas molecules under vacuum. He presented this 8 years after he had joined new research laboratory of the General Electric Company where he worked for the rest of his career, in various capacities, all the way up until his death in 1957.
This fascination with surface chemistry continued and for this he became non-academic chemist to receive the Nobel Prize. Working with Blodgett he developed the field of surface science which has become a fully-fledged scientific discipline in its own right. Their phase studies clarified surface adsorption and established the existence of monolayers: indeed in the author’s research time one monolayer was referred to as one Langmuir.
Langmuir though had an incredible breadth of other research activities2: heat transfer, incandescent lamps (one of his developments reduced the electrical power consumption in the US by what was then an amazing $1M per day), isotopes, electrical discharges, plasmas and their oscillations, the atomic and molecular structure of matter, proteins, filtration and aviation. His war time contributions ranged from submarine detection in WW1 and amongst other to radar and the development of the artificial smoke screen in WW2. From the latter a dry-ice seeding technique would be used to initiate rainfall and to overseed clouds to prevent dangerous weather conditions, for example to prevent hail damage to crops.
An amazing range but this writer's professed favourite was the idea behind the rotating disc gauge for high vacuum pressure measurement. 75 years later the author would reproduce this work and improve its range and accuracy by a factor of 10 – a source of great pride. This instrument was also utilized to study gas-surface interactions again confirming Langmuir’s early theorem
Langmuir was not noted for his small talk and contemporary accounts indicateded that could come over as rather conceited and brusque. He did however like to lecture on a wide range of scientific and social issues. His company was regularly sought and his laboratory was visited by luminaries including Edison, Coolidge, Thomson and Marconi. He sat for the official photograph of the Fifth Solvay Congress3; Brussel, 1927: the capturing together the greatest meeting attended by some of the greatest scientists of all time discussing the newly formulated Quantum Theory.
His Nobel Prize acceptance speech4 in 1932 gives an insight to his philosophy:
“Science, almost from its beginnings, has been truly international in character. National prejudices disappear completely in the scientist's search for truth. Medicine also disregards national boundaries. And literature frequently rises to heights that make it international.
The scientist is motivated primarily by curiosity and a desire for truth. His attitude is objective rather than subjective. In his work he finds great satisfaction in discovering new facts or new relationships between known facts, but even greater pleasure is derived from seeing his results incorporated into the body of scientific knowledge and from seeing them willingly used by others in the further development of science.”
General Electric gained 62 patents from Langmuir in return for funding his research efforts; he became the first industrial based scientist to win the Nobel Prize and became a true Hero of Vacuum.
References
1) Proceedings of the National Academy of Sciences, Vol.3 (3) p141
2) http://www.ee.nmt.edu/~langmuir/langmuir.html
3) Fifth Solvay International Conference on Electrons and Photons Brussels October 1927
4) From Les Prix Nobel en 1932, Editor Carl Gustaf Santesson, [Nobel Foundation], Stockholm, 1933.
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