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Curie (kürēˈ), family of French scientists. Pierre Curie, 1859–1906, scientist, and his wife, Marie Sklodowska Curie, 1867–1934, chemist and physicist, b. Warsaw, are known for their work on radioactivity and on radium. The Curies' daughter Irène (see under Joliot-Curie, family) was also a scientist.
Pierre Curie's early work dealt with crystallography and with the effects of temperature on magnetism; he discovered (1883) and, with his brother Jacques Curie, investigated piezoelectricity (a form of electric polarity) in crystals. Marie Sklodowska's interest in science was stimulated by her father, a professor of physics in Warsaw. In 1891 she went to Paris to continue her studies at the Sorbonne. In 1895 she married Pierre Curie and engaged in independent research in his laboratory at the municipal school of physics and chemistry where Pierre was director of laboratories (from 1882) and professor (from 1895).
Following A. H. Becquerel's discovery of radioactivity, Mme Curie began to investigate uranium, a radioactive element found in pitchblende. In 1898 she reported a probable new element in pitchblende, and Pierre Curie joined in her research. They discovered (1898) both polonium and radium, laboriously isolated one gram of radium salts from about eight tons of pitchblende, and determined the atomic weights and properties of radium and polonium. The Curies refused to patent their processes or otherwise to profit from the commercial exploitation of radium. For their work on radioactivity they shared with Becquerel the 1903 Nobel Prize in Physics.
The Sorbonne created (1904) a special chair of physics for Pierre Curie; Marie Curie was appointed his successor after his death in a street accident. She also retained her professorship (assumed in 1900) at the normal school at Sèvres and continued her research. In 1910 she isolated (with André Debierne) metallic radium. As the recipient of the 1911 Nobel Prize in Chemistry she was the first person to be awarded a second Nobel Prize. She was made director of the laboratory of radioactivity at the Curie Institute of Radium, established jointly by the Univ. of Paris and the Pasteur Institute, for research on radioactivity and for radium therapy.
During World War I, Mme Curie devoted her energies to providing radiological services for hospitals. In 1921 a gram of radium, a gift from American women, was presented to her by President Harding; this she accepted in behalf of the Curie Institute. A second gram, presented in 1929, was given by Mme Curie to the newly founded Curie Institute in Warsaw. Five years later she died from the effects of radioactivity. In 1995 Marie and Pierre Curie's ashes were enshrined in the Panthéon, Paris; she was the first woman to be honored so in her own right.
Among the numerous and valuable writings of the Curies are Marie Curie's doctoral dissertation, Radioactive Substances (2 vol., 1902; tr. 1961); Traité de radioactivité (1910); Radioactivité (1935); and her biography of Pierre Curie (1923, tr. 1923). Pierre Curie's collected works appeared in 1908. A biography of Marie Curie was written by her daughter Ève Curie (tr. 1937). See also biographies by R. W. Reid (1974), F. Giroud (tr. 1986), S. Quinn (1995), and B. Goldsmith (2004); S. Emling, Marie Curie and Her Daughters (2012).
a subsidiary unit of the activity of a nuclide in a radioactive source (activity of an isotope). The unit was named in honor of the French scientists P. Curie and M. Sklodowska Curie. It is abbreviated Ci in international usage. The curie unit was originally defined (1910) as the quantity of radon (radium emanation) in radioactive equilibrium with 1 g of radium. The quantity of radon corresponding to 1 curie has a mass of 6.51 × 10–6g and contains 1.78 × 1016 atoms. Measurements of the disintegration of radon with an activity of 1 Ci have yielded 3.7 × 1010 disintegrations per second. Refinement of the experimental data later led to abandonment of the relationship between the curie unit and the quantity of radon. The curie unit is the activity of any nuclide in which 3.700 × 1010 disintegrations take place per second.