Kathleen Lonsdale (1903-1971)
Born in Ireland, Kathleen Lonsdale studied at Bedford College for Women and earned an MSc in physics from University College London in 1924. She discovered the structure of the benzene ring and contributed to diamond synthesis, with Lonsdaleite named in her honour.
A leading theorist in X-ray crystallography, she was one of the first female Fellows of the Royal Society in 1945. Lonsdale and her husband became Quakers in 1935, and she was a committed pacifist, anti-nuclear campaigner, and prison reformer. She served as President of the Women’s International League for Peace and Freedom and was imprisoned during World War II for refusing civil defence duties.