Energetics, structure, and rovibrational spectroscopic properties of the sulfurous anions SNO⁻ and OSN⁻

The SNO⁻ and OSN⁻ anions are shown in this work to be very stable negatively charged species in line with other recent work [T. Trabelsi et al., J. Chem. Phys. 143, 164301 (2015)]. Utilizing established quartic force field techniques, the structural and rovibrational data for these anions are produced. The SNO⁻ anion is less linear and has weaker bonds than the corresponding neutral radical giving much smaller rotational constants. OSN⁻ is largely unchanged in these regards with inclusion of the additional electron. The S–N bond is actually stronger, and the rotational constants of OSN⁻ versus OSN are similar. The vibrational frequencies of SNO⁻ are red-shifted from the radical while those in OSN⁻ are mixed. OSN⁻ has mixing of the stretching modes while the S–N and N–S stretches of SNO⁻ are largely independent of one another. The ω₃ stretches are much brighter in these anions than they are in the radicals, but the ω₁ stretches are still the brightest