Having the ability to predict the nature and amounts of plutonium emissions in industrial accidents, such as in solvent fires at PUREX nuclear reprocessing facilities, is a key concern of nuclear safety agencies. In accident conditions and in the presence of oxygen and water vapor, plutonium is expected to form three major volatile species PuO₂, PuO₃, and PuO₂(OH)₂, for which the thermodynamic data necessary for predictions (enthalpies of formation and heat capacities) presently shows either large uncertainties or is lacking. In this contribution we discuss in detail the electronic structure of these gas-phase plutonium species, highlighting the challenges of relativistic correlated electronic structure methods to accurately predict their thermodynamics properties [1]. We showcase the use of these quantum chemical data to predict the forms and quantities of the released plutonium species under accidental conditions [2]. [1] K. Boguslawski, F. Réal, P. Tecmer, C. Duperrouzel, A. S. P. Gomes, Ö. Legeza, P. W. Ayers, and V. Vallet, Phys. Chem. Chem. Phys. 19, 4317 (2017) [2] S. Kervazo, F. Réal, F. Virot, A. S. P. Gomes, V. Vallet arXiv:1906.03157 (2019).