Geometries, vibrational frequencies, and electron affinities of X2Cl (X-C, Si, Ge) clusters

摘要

Ab initio quantum chemical calculations have been performed on X2Cl- and X2Cl (X = C, Si, Ge) clusters. The geometrical structures, vibrational frequencies, electronic properties and dissociation energies are investigated at the Hartree-Fock (HF), Moller-Plesset second- and fourth-order (MP2, MP4), CCSD(T) level with the 6-311+G(d) basis set. The X2Cl (X = C, Si, Ge) and X2Cl- (X = Si, Ge) take a bent shape obtained at the ground state, while C2Cl- has a linear structure. The impact on internal electron transfer between the X2Cl and the corresponding anional clusters is studied. The three different types of electron affinities (EAs) at the CCSD(T) are reported. The most reliable adiabatic electronic affinities, obtained at the CCSD(T)/cc-pvqz level of theory, are predicted to be 3.30, 2.62, and 1.98 eV for C2Cl, Si2Cl, and Ge2Cl, respectively. The calculated EAs of C2Cl and Ge2Cl are in good agreement with theoretical results reported. The correlation effects and basis sets effects on the geometrical structures and dissociation energies are discussed. (C) 2006 Wiley Periodicals, Inc.