FSO+ and FSO2+ ions from ionised sulfur oxyfluorides: a computational investigation on the structure, stability, and thermochemistry

Singlet and triplet F-S-O+, F-O-S+, F-S(O)-O+, and FO-SO+ isomers have been investigated at the Coupled Cluster, G2, and G3 theoretical levels. At the CCSD(T)/aug-cc-pVTZ//CCSD/cc-pVDZ, the F-S-O+ isomer 1S (S-1') and the F-S(O)-O+ isomer 3S ((1)A(1)) resulted the global minima on the singlet surfaces, more stable than the corresponding triplet by approximate to64 and 47 kcal mol(-1), respectively. The G2 and G3 estimates of the enthalpies of formation of the various singlet and triplet FSO+ and FSO2+ isomers allow to identify the species observed from the photon and electron ionization of the simplest sulfur oxyfluorides as the ions 1S and 3S.