Materials Research Activities

Paul Caro introduction

Paul Caro

Born in 1934, studied chemistry at the Ecole nationale supérieure de chimie de Paris (ENSCP), where he was attracted to Rare Earths chemistry (the f-elements) by one of the Professors, Félix Trombe (1906-1985) himself a student of Georges Urbain (1872-1938) one of the main promoters of the study of Rare Earths in France. Another student of Urbain teaching at the school was Paul Job who presented the chemistry of mineral "complexes" of d-elements which was to became later coordination chemistry. Paul Caro entered the Centre national de la recherche scientifique (CNRS) in 1955 and started his own research on rare earths elements or lanthanides in Trombe's laboratory. After he got his Ph D degree in 1962, (after two years in the military service …), he spent a few years in the United States, first in Leroy-Eyring's laboratory at Tempe in Arizona, specialized in rare earths non-stoechiometric oxides, then in Ames (Iowa) "the Mecca for rare earth chemists" where Rare Earth separation was done in the framework of the Manhattan project. During the 1960s the rare earths elements, already strategic in nuclear research as a model for separating actinides, became even more important because of their optical properties as unique materials for colour TV screen and lasers. Back in Paris, in 1969, Caro became deputy-director of the Laboratoire des terres rares located on the CNRS campus in Bellevue-Meudon. There he developed the experimental spectroscopy of lanthanides in solids and the theoretical interpretation (simulation) of the spectra (made of numerous sharp lines), using theoretical and mathematical tools, in particular Giulio Racah's algebra and tensor operator formalism made possible by the appearance of powerful computers. He also made extensive use of high resolution electron microscopy. In 1989, Caro started a second career as a science writer and popularizer.

Paul Caro who became corresponding member of the Academy of Sciences in 1978 was awarded the first Lecoq de Boisbaudran Prize set up by Rhodia Company in 2000. He has been the President of the Solid State Chemistry Division of the Société française de chimie (1985-89) and the President of the Association française pour l'avancement des sciences (AFAS) (1991-93).

Our interview is of special interest for rare earths science and applications, for the role of instruments in this domain and for the connections between science and industry in France.

This page was last updated on 16 October 2002 by Arne Hessenbruch.