Who was the French scientist Rosalind Franklin collaborated with in Paris?

The French scientist Rosalind Franklin collaborated with in Paris was Jacques Mering. Franklin joined Mering’s laboratory at the Laboratoire Central des Services Chimiques de l’État on 14 February 1947, after being introduced to him through Adrienne Weill and Marcel Mathieu.

Mering was an X-ray crystallographer who studied amorphous materials such as rayon, coal, and graphite rather than only well-ordered crystals. Under his guidance, Franklin learned practical methods for applying X-ray diffraction to difficult, non-crystalline substances. This training became a crucial foundation for her later DNA research at King’s College London.

Franklin spent several years in Paris and published important work on carbon and coal. She helped distinguish graphitising from non-graphitising carbon, and her Paris experience strengthened her reputation as an exceptionally careful experimental scientist. Marcel Mathieu is an easy name to confuse with Mering: Mathieu helped connect Franklin with the French research system, but Mering was the scientist who headed the laboratory where she worked.