COMBINING DOUBLY-CHARGED CATIONS AND ANIONS TO FORM NEW SPECIES

In this study we predict, based on our ab initio electronic structure calculations, the existence and relative stabilities of several new sp ecies such as H3SMgF3, H2SMgF2, and HSMgF derived from combining the g eometrically metastable and electronically stable parent doubly charge d ions H4S+2 and MgF4-2. Although this study focuses on compounds obta ined from these particular double ions, we suggest that analogous obse rvations will be obtained when other double ions are used. Stable stru ctures of the HSMgF, and H2SMgF2 molecules, as well as a local energy minimum and two different second-order saddle point geometries for the H3SMgF3 molecule were found. The lowest-energy stable structure is th at found for H3SMgF3, which is best described as a dative adduct of H2 S, MgF2, and HF, and which lies approximately 570 kcal/mol below the s eparated-ion starting materials and approximately 140 kcal/mol below t he (H4S+2) (MgF4-2) contact ion pair.