Stabilization of metastable hydrogen trioxide (HOOOH) and the hydrotrioxyl radical (HOOO) by complexation with sulfuric acid. A theoretical study

► Neutral and radical H2SO4/polyoxide species stabilized through complexation. ► Counterpoise corrected DFT and highly accurate CCSD(T)-F12 employed. ► Trans conformations of polyoxide species are favored upon complexation. ► Polyoxide species may participate in the nucleation of atmospheric H2SO4 aerosol.