Stability analysis of the neutral noble gas molecules FNgX and their anions FNgX− (Ng = He, Ar, Kr; X = O, S)

The structural stability and bonding energies of the neutral noble gas molecules FNgX and their anions FNgX− (Ng = He, Ar, Kr; X = O, S) are discussed at the CCSD(T)/aug-cc-pVnZ (n = D, T) levels. Results reveal that only two neutral FKrX molecules are stable, whereas their FHeX and FArX counterparts are not. All their anions are stable and the stability mainly derives from the contribution of the extra electron, i.e., the attachment of the electron greatly enhances the orbital interactions of two bonds, FNg and NgX. Different from the anion counterparts, the electrostatic interaction energy plays a crucial role in the FKrX stability. Compared with those unstable FHeX and FArX counterparts, the enough charge distribution over each atom of FKrX ensures the effective bonding between F and Kr, and between Kr and X, consequently strengthen the stability of the neutral FKrX (X = O, S) structures. © 2008 Wiley Periodicals, Inc. Int J Quantum Chem, 2009