Thermochemistry, bond energies, and internal rotor potentials of dimethyl tetraoxide

Abstract

Thermochemical properties of dimethyl tetraoxide (CH 3OOOOCH 3), the dimer of the methylperoxy radical, are studied using ab initio and density functional theory methods. Methylperoxy radicals are known to be important intermediates in the tropospheric ozone cycle, and the self-reaction of methylperoxy radicals, which is thought to proceed via dimethyl tetraoxide, leads to significant chain radical termination in this process. Dimethyl tetraoxide has five internal rotors, three of them unique; the potential energy profiles are calculated for these rotors, as well as for those in the CH 3OO, CH 3OOO, and CH 3OOOO radicals. The dimethyl tetraoxide internal rotor profiles show barriers to rotat..