She left for Berlin in 1907 with family support, to attend Dr Max Planck’s lectures and to do radio-activity research with chemist Dr Otto Hahn. After a year, she became his Hahn’s assistant and worked with him, wanted to discover isotopes. In 1913 physicist Meitner and chemist Hahn collaborated at Kaiser Wilhelm Institute of Chemistry in Berlin.
Having isolated the isotope protactinium, Meitner and Hahn studied nuclear isomerism and beta decay. In 1926 she became the first female Professor of Physics in Germany, heading up the Physics Dept at Kaiser Wilhelm Institute for Chemistry. Research at the time was theoretical, but many scientists knew about the honour of the Nobel Prize waiting for the winner who discovered it. She worked with Hahn for 30 years, collaborating closely, studying radioactivity, with her physics skills and his chemistry skills.
In the 1930s with the German physical chemist Dr Fritz Strassmann, she investigated neutron bombardment of uranium. Strassmann was not Jewish but he refused to join the Nazi Party, so both their research efforts were interrupted as the Nazis gained power. She stayed in Germany longer than most because of her Austrian citizenship, but because she was Jewish, her physicist friends had to help sneak her over the border when Austria was annexed by Germany in 1938. Then she worked in Sweden at the Nobel Institute for Experimental Physics, then continued her laboratory work at Stockholm’s Manne Siegbahn Institute, developing a working relationship with Niels Bohr.
Physicist Dr Otto Frisch (1904–79) was the Austrian-born first cousin of Lise Meitner. He first measured the magnetic moment of the proton and together they advanced the first theoretical explanation of nuclear fission and first detected the fission by-products.
While working together, Otto Frisch and Lise Meitner received the news that Otto Hahn and Fritz Strassmann had discovered that the collision of a neutron with a uranium nucleus produced the element barium as one of its by-products. Frisch and Meitner both hypothesised that the uranium nucleus had split in two, coining the term nuclear fission to describe the process. After Hahn and Strassmann showed that barium appeared in neutron-bombarded uranium, it was Meitner and Frisch who explained the physical characteristics of this division.
Hahn had isolated evidence for nuclear fission, but Meitner and Frisch were the first to clarify how the process occurred. Yet in 1944 Hahn alone received the Chemistry Nobel Prize regarding nuclear fission, given that he ignored Meitner’s research after she left Germany. He should have argued that Meitner merited the Nobel Prize as well.
After WW2 Meitner continued working in Sweden, then travelled and lectured across the USA. Her recognition of the explosive potential of the process was what motivated Dr Albert Einstein to contact Pres Roosevelt, leading to the establishment of the Manhattan Project. She was then invited to work on the Project at Los Alamo but Meitner opposed the atomic bomb and refused to work there at all.
On a visit to the U.S in 1946 she was welcomed by her siblings, and given total American press celebrity treatment, including being named Woman of the Year by the Women's National Press Club, DC. She had dinner with Pres Harry Truman who mistakenly thought that she worked on the atomic bomb but Lise Meitner refused to work on a bomb.
Her Swedish colleagues planned to get her a proper position. In 1947, Meitner moved to Stockholm’s Royal Institute of Technology to establish a new facility for atomic research, with researchers to help. Appropriately she received in the Max Planck Medal, honouring her old mentor in Berlin.
The physicist who never lost her humanity died in Cambridge in Oct 1968. In 1992, element 109 was named Meitnerium in her honour. Like many others, I believe she was the most significant woman scientist of the 20th century!