Infrared Spectra of Novel NgBeSO2 Complexes (Ng = Ne, Ar, Kr, Xe) in Low Temperature Matrixes.

The novel noble-gas complexes NgBeSO2 (Ng = Ne, Ar, Kr, Xe) have been prepared in the laser-evaporated beryllium atom reactions with SO2 in low-temperature matrixes. Doped with heavier noble gas, the guest (Ar, Kr, Xe) atom can substitute neon to form more stable complex. Infrared spectroscopy and theoretical calculations are used to confirm the band assignment. The dissociation energies are calculated at 0.9, 4.0, 4.7, and 6.0 kcal/mol for NeBeSO2, ArBeSO2, KrBeSO2, and XeBeSO2, respectively, at the CCSD(T) level. Quantum chemical calculations demonstrate that the Ng-Be bonds in NgBeSO2 could be formed by the combination of electron-donation and ion-induced dipole interactions. The Wiberg bond index (WBI) values of Ng-Be bonds and LOL (localized orbital locator) profile indicate that the Ng-Be bond exhibits a gradual increase in covalent character along Ne to Xe.