Quantum chemical calculations on FXeSiF

Quantum chemical calculations on FXeSiF are reported. The equilibrium struc ture, energetics, harmonic and anharmonic vibrational frequencies, and an a nalysis of the nature of bonding, is presented. All calculations are made a t the MP2 level, while energetics is also considered via single-point CCSD( T) calculations. Energetical considerations of FXeSiF suggest that it shoul d be stable compared to its decomposition pathways either via its bending c oordinate to Xe + SiF2 or via the stretching coordinate to F + Xe + SiF. An alysis of electron localization function (ELF) indicates that both fluorine s are bound by interactions of unshared-electron type, i.e. by ionic intera ctions. The Xe-Si bond, however, is shown to be covalent, and this is the f irst time a covalent Xe-Si bond is predicted in a neutral molecule. (C) 200 1 Elsevier Science B.V. All rights reserved.