The conformational potential energy surface of IOONO and the isomerization and decomposition processes

The conformational potential energy surface of iodine peroxy nitrite was investigated using high levels of electronic structure theory. Two minimum energy conformers and five energy maxima have been determined. The comparison with other peroxy nitrites shows interesting correlations with the internal rotational barriers of the Cl, Br analogues and with peroxynitrous acid. Distinct transition states for the isomerization to iodine nitrate and the scission of the peroxy bond have been calculated. Finally, the thermochemistry of IOONO and IONO2 has been reconsidered.