Isabel Gonzalez Vallejo was awarded the 2020 PhD thesis prize from Association Française de Cristallographie de Physique de la Matière Condensée. Her PhD thesis was directed by Prof. Jérôme Faure (Laboratoire d’Optique Appliquée) and Dr. David Le Bolloc’h (Laboratoire de Physique des Solides). During her PhD work, Dr. Gonzalez Vallejo used ultrafast electron and X-ray diffraction to study the structural dynamics of various phase transitions. Her main results were obtained on the charge density wave photo-induced phase transition in RTe3 compounds. She also studied successfully the effect of electron multiple scattering in ultrafast electron diffraction experiments and how they need to be taken into account for providing correct interpretations to experimental observations.