Professor at the University Paris Diderot 1968 –1981 : Assistant-Professor at University of Paris Diderot 1981 –2012 : Professor at the University of Paris 2012 - :Professor « Emeritus » at the University of Paris, Matériaux et Phénomènes Quantiques, CNRS Direction of Research Laboratories at the University of Paris 1982 -1996 : Director of the Laboratory of Surface Magnetism, University of Paris Diderot 1997-2000 : Director of the Theoretical Physics of the Condensed Matter, University of Paris Diderot 2001-2009 : Director of the International Center, CIUP, University of Paris Distinction : Medal of the Institute of Industrial Sciences, Tokyo, Japan, 2004 Foreign Positions 1/01/1967 – 31/12/1969 : Research Associate at Ohio State University, Columbus, Ohio, USA 1990-99 : 18 months as Invited Research Associate at the Universities of Osaka, Kyoto and Tokyo, 1999 : 3 months at the University of Leiden, Nederlands 2012- 2019: Invited Research Associate at the Universities of Sao Carlos and Belo Horizonte, Brasil Edition Editorial Committees : « Progress in Surface Science », Pergamon – Elsevier 1994-2003 Physical Review , J. Catalysis, Surf. Science, Optics Comm. 1986-2001 Book : Electronic Processes at Solid Surfaces, World Scientific, Singapore 1997 Patents "Procédé de conversion d'ortho- en para-hydrogène" : France, R.F.A,. U.S.A. G.B. Japan, 1970 Reservoir Ouvert à Hydrogène, France, Europe, 2021