Feng-You Hao

Bonding analysis for NgMOH (Ng=Ar, Kr and Xe; M=Cu and Ag)

The structures and stabilities of a new class of species, noble-gas–coinage-metal hydroxides NgMOH (Ng  = Ar, Kr and Xe; M  = Cu and Ag), are investigated at the MP2 theoretical level. All species are found to be in Cs symmetry with an approximate linear Ng–M–O moiety. The noble-gas–coinage-metal bond lengths are in the range of the respective covalent and van der Waals limits, showing a different degree of approach to the former along the series Ar–Kr–Xe for Ng–Cu and Ng–Ag bonds, respectively. The dissociation energies of noble-gas–coinage-metal bonds are relatively large as compared to the van der Waals complexes. Besides the charge-induced dipole contribution, other effects  – higher-order charge-induction energies, dispersion interaction, etc., should be considered to explain the noble-gas–coinage-metal bonding mechanism. The present results suggest that the title species are stable enough to be prepared experimentally.

Geometrical and electronic structures of the SnnCl and SnnCl- (n = 1-6) clusters

Theoretical studies of the structures of Sn n Cl and Sn n Cl− (n = 1–6) clusters have been carried out using density functional theory methods. The geometric structure of each unit is optimized at the B3LYP level, employing the LANL2DZpd for tin and DZP++ for chlorine basis sets. The resulting total energies, fragmentation energies and equilibrium geometries of chlorine–tin clusters are presented and discussed, together with natural populations and natural electron configurations. The impact on internal electron transfer between the (Sn n ) subsystem and Cl atom in Sn n Cl− (Sn n Cl) clusters is investigated. In addition, theoretical results for the electron affinities of Sn n Cl (n = 4–6) clusters are in good agreement with experimental results available.

Ab Initio Study of Structure and Stability of M2Al2 (M = Cu, Ag, and Au) Clusters

Coinage metal aluminium clusters M2Al2 (M = Cu, Ag, and Au) were studied by Hartree–Fock (HF) and second-order Moller–Plesset perturbation theory (MP2) with pseudopotentials. It was found that the butterfly structure with C2v (1A1) symmetry is more stable than the planar structure, and Au2Al2 is the most stable of the title species. The binding energies and the highest occupied molecular orbital and the lowest unoccupied molecular orbital (HOMO–LUMO) gap are evaluated, which indicates that doping clusters M2Al2 are more stable than the pure clusters M4 (M = Cu, Ag, and Au). Electron correlation and relativistic effects stabilize the present species.