Leif Tronstad and the heavy water

Chemistry professor and resistance fighter Leif Tronstad was an important contributor to one of the most famous sabotage missions of World War II: the destruction of Norsk Hydro’s heavy water plant at Vemork in Telemark.

The picture shows a potentiometer and a rotameter, which were both probably used in experiments with heavy water.
Tronstad and his researcher colleagues published several articles about heavy water – “the heavy hydrogen” – in publications including the leading natural science journal “Nature”. Photos: Per Henning/NTNU.

Tronstad, born in 1903, was educated at NTNU’s precursor, the Norwegian Institute of Technology (NTH) and later became a professor of inorganic chemistry. He had an extensive international network, and some 80 research publications. Heavy water (Gemini article in Norwegian) was one of his fields of interest, and before the war he worked as a consultant for Norsk Hydro when the company was building the heavy water plant at Vemork in Telemark.

Leif Tronstad (born on 27 March 1903 in Bærum, died on 11 March 1945 at Syrbekkstøylen in Rauland) was a chemistry professor at the Norwegian Institute of Technology, an intelligence officer and military organizer during the resistance movement in World War II.
Reference: Leif Tronstad. Archives [Tek.60] (NTNU University Library).
During World War II, Tronstad distinguished himself in the resistance movement in Norway. He helped to train Norwegian resistance fighters in the United Kingdom. Tronstad’s knowledge of heavy water and Norsk Hydro’s heavy water plant made him a key contributor to the sabotage mission.

The background for the sabotage was the fear that the heavy water would be used in producing atomic weapons in Germany. The mission took place during the night from 27 to 28 February 1943.

In 1944, Tronstad returned to Norway as the leader of a underground resistance group in Telemark, but was killed in a clash with Norwegian Nazi sympathizers during the spring of 1945.

This article is based on an internet exhibition created by the Faculty of Natural Sciences at NTNU.

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Glass tubes filled with heavy water. They were used in experiments to investigate the reaction of various metal samples to the heavy water.
Results from such experiments would have been extremely important in the use of heavy water in connection with nuclear power plants. For example, corrosion in containers of heavy water would be disastrous.
Reference: NTNU’s university history collections. Photos: Per Henning/NTNU.


With thanks to the NTNU University Library, Kjell Røkke and Geir Martin Haarberg – NTNU and NTNU University Museum.


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