Lise Meitner: “A New Nuclear Reaction”

Theoretical physics: the scientific revolution that peaked in the early 1900s.

This particular field of study is littered with names of famous men: Albert Einstein, Max Planck, James Clerk Maxwell, Ludwig Boltzmann, and more. These men, among many others, made incredible contributions to theoretical physics and changed the way we understand physical science. But there are a few women who boldly ventured into this testosterone-ridden field. Lise Meitner was one of them.

Meitner was born in 1878 to a wealthy Jewish family in Vienna. At the time, women were barred from attending institutions of higher education. But she desperately wanted to learn, so her family privately funded her education.

In 1905, she became the second woman ever to earn a doctorate in physics from the University of Vienna. From there she traveled to Berlin, where fate would bring her into the crosshairs of legendary people like Planck and Einstein.

At first, Planck refused to teach women. Meitner attended his lectures on theoretical physics regardless and soon became his research assistant. It was in Planck’s lab that she met Otto Hahn.

Hahn was a chemist – a great chemist, and they were a great team. Together they discovered new isotopes, studied beta radiation, and took on some of the biggest scientific challenges of their time.

Hahn and Meitner

In 1912, the duo moved to the new Kaiser Wilhelm Institute in Berlin. Despite being a team, Meitner worked without pay under Hahn’s leadership. She eventually garnered a paid position, and in 1917 was named head of her own physics department. Theoretical physics was a competitive field at the time, with the very basics of atomic and molecular theory being called into question. The competition became obvious in 1923.

Meitner made a discovery in 1922 – she noticed that if an electron was removed from the inner shell of an atom, an electron from a higher shell would move to fill the vacancy. This caused a release of energy unique to the element. She published these results in 1922. However, a French chemist Pierre Auger, independently published the same results in 1923. To this day, the phenomenon is called the “Auger Effect” despite Meitner’s discovery made a year earlier than Auger’s.

Adolf Hitler’s rise to power in 1933 certainly complicated matters. At first, her Austrian citizenship was enough to keep her safe. But eventually, it became clear that she would have to flee. She escaped to Sweden where she continued her work in private. By now, researchers had discovered the neutron and scientists were trying to decide if you could make elements heavier by bombarding them with neutrons.

Hahn and his colleagues were performing these neutron bombardment experiments, but he was baffled by the results: neutron bombardment created lighter elements. He couldn’t decipher a reasonable explanation for the results, so he secretly consulted Meitner.

“Perhaps you can come up with some sort of fantastic explanation. We knew ourselves that uranium can’t actually burst apart into barium.” – Hahn in a letter to Meitner

And here is where Meitner’s claim to fame comes into the picture – she came up with the theory of nuclear fission, which explained Hahn’s results. And when Hahn published his chemical evidence for nuclear fission, she was not listed as a co-author.

In February of 1939, Meitner published her own paper in the journal Nature called “Disintegration of Uranium by Neutrons: A New Type of Nuclear Reaction.” Regardless, she was overlooked by the Nobel Prize Committee in 1944 when they awarded Hahn with the Nobel Prize in Chemistry. It is rumored that Hahn felt incredibly guilty about this oversight, and independently submitted Meitner’s work to the Nobel Prize committee over ten times. But to no avail.

Meitner, alongside scientists like Einstein, recognized the incredible power of nuclear fission. She knew it could be harnessed into a dangerous weapon. She was offered a job to work on the Manhattan Project in Los Alamos, to which she said “I will have nothing to do with a bomb.”

Stamp issued in honor of Meitner

She didn’t go entirely unrecognized – she was awarded Woman of the Year in 1946 by the National Press Club in a visit to the United States to meet the President. She and her colleagues were also awarded the prestigious Enrico Fermi Prize in 1966. Unlike most women of the time, she held high-ranking academic positions and received a salary.

But science is a collaborative practice – very rarely is a discovery made by a single person. Credit must be given where credit is due. Otto Hahn did not discover nuclear fission alone. Meitner’s story defines the scientific revolution regarding theoretical physics: fierce competition, incredible discoveries, and accrediting the theories that explain our world.

Dorothy Hodgkin: “Gifted Intuition”, Brilliant Chemist

Dorothy Hodgkin wanted to be an archaeologist, like her parents. She grew up traveling between Sudan, Cairo, England – all the while becoming curious about the world. She saw her father pursue his passion of archaeology, even after his retirement. She considered studying it when she went off to school.

But her mind was occupied elsewhere. Archaeology was not the field to which Dorothy brought her talent. Instead, she became entranced with the world of chemistry. Her interest in chemistry began at the young age of 10. She attended Sir John Leman School in Beccles, UK from 1924 to 1928. There, she was one of two girls allowed to study chemistry with the boys.

Stamp honoring Dorothy issued in the UK

She remained endlessly fascinated by the subject. When it came time to attend college, she went to Somerville College and initially combined her passions – archaeology and chemistry. But as the years went on, she was encouraged to do research involving a brand new technology: x-ray crystallography.

X-ray crystallography is a tool used to determine the molecular structure of a substance via diffraction. Sir William Henry Bragg and his son are credited with inventing the technique. An incoming beam of x-rays is passed through a substance. The crystal structure of the substance diffracts the beam of light – in other words, the substance’s structure interferes with the beam and sends it off in multiple directions. The angle by which the beam changes can tell scientists what the structure of the substance looks like.

Dorothy Hodgkin became deeply fascinated by x-ray crystallography. In 1932, she traveled to Cambridge to work with Dr. J.D. Bernal. They were interested in sterols, a class of organic molecules, the most well known being cholesterol.

Dorothy quickly distinguished herself in the field. She became a leading expert on the use of x-ray crystallography. Her work did not go unrecognized. She was elected a fellow to the Royal Society in 1947, a member of the Royal Netherlands Academy of Science in 1956, and finally a member of the American Academy of Arts and Sciences in 1958.

A 3D model of the structure of penicillin. Dorothy identified the structure using x-ray crystallography in 1945. 

Her most prestigious award? The Nobel Prize in Chemistry in 1964. She was the 3rd woman to ever win a Nobel Prize in Chemistry (following the famed Curie mother-daughter pair). She was awarded for using x-ray crystallography to determine the structure of penicillin and vitamin B12. Thus began the widespread use of x-ray crystallography as a means to determine the structure of organic matter.

Scientists working in many different fields admire the great determination and skill involving what can only be described as gifted intuition, which has always been the mark of your work. – Royal Society to Dorothy Hodgkin, Nobel Prize Award Ceremony

Here is video footage provided by the Nobel Prize website of Dorothy claiming her prize on December 10th, 1964. She is gracious, curtsying politely as she returns to her seat with the Prize. Surrounded by a sea of men in black and white suits, she stands out. Bold in her resolve, Dorothy Hodgkin never settled. She worked tirelessly and changed the field of chemistry forever.

Dorothy Hodgkin (1910-1994)