Small germanium sulfide clusters: mass spectrometry and density functional calculations.

Germanium sulfide clusters were generated by laser ablation of a solid sample. The resulting molecules were analyzed in a time-of-flight mass spectrometer. In addition to atomic germanium and diatomic sulfur, the spectra exhibited evidence for the existence of clusters containing up to four germanium atoms.

Experimental and computational study of the Zn(n)S(n) and Zn(n)S(n)+ clusters.

Zinc sulfide clusters produced by direct laser ablation and analyzed in a time-of-flight mass-spectrometer, showed evidence that clusters composed of 3, 6, and 13 monomer units were ultrastable. The geometry and energies of neutral and positively charged Zn(n)S(n) clusters, up to n = 16, were obtained computationally at the B3LYP/6-311+G level of theory with the assistance of an algorithm to generate all possible structures having predefined constraints. Small neutral and positive clusters were found to have planar geometries, neutral three-dimensional clusters have the geometry of closed-cage polyhedra, and cationic three-dimensional clusters have structures with a pair of two-coordinated atoms.

Experimental and computational study of small (N = 1-16) stoichiometric zinc and cadmium chalcogenide clusters.

Zinc selenide, cadmium sulfide, and cadmium selenide clusters were produced by direct laser ablation and analyzed in a time-of-flight mass spectrometer. The positive-ion mass spectra indicated that clusters composed of six and thirteen monomer units were ultrastable in all cases. The geometries and energies of the neutral and positively charged M(n)X(n) clusters up to n = 16 were obtained computationally at the B3LYP level of theory using the SKBJ basis set for the metal atoms and the SKBJ(d,2df) basis set for the chalcogen atoms.