Crassous investigates π-conjugated chiral systems. She returned to École normale supérieure de Lyon in 1998, where she worked with Laure Guy and Jean-Pierre Dutasta optical properties of chiral molecules.[2] In 2005, she moved to the Institut des Sciences Chimiques de Rennes, where she joined the research group of Régis Réau. Crassous was made Director of Research at the French National Centre for Scientific Research (CNRS) in 2010.[citation needed]
At the CNRS, Crassous leads the research programme CHIRAFUN, in which research teams investigate the molecular and supramolecular chirality of chiral materials.[3] She has investigated the stereochemistry of a range of small molecules, including fullerenes, helicenes and organometallic complexes.[4] In 2020 Crassous became the coordinator of HEL4CHIROLED, a collaborative international programme that looks to develop efficient organic light-emitting diodes from chiral materials.[5][6]
Crassous serves on the editorial board of the Wiley journal Chirality.[7]