Assessment of density functional methods for thermochemistry of chromium oxo compounds and their application in a study of chromia-silica system

► An accuracy of DFT methods in thermochemistry of chromium oxo compounds is tested. ► Relative stabilities of Cr(VI) species on SiO2 are predicted using cluster models. ► Both monooxo and dioxo Cr(VI) surface species can exist under dehydrated conditions.