Geometries of small tungsten clusters

Geometries of anionic, neutral, and cationic small tungsten clusters Wn (n = 3-6) have been studied using a density functional method. For each cluster studied, a number of low-lying states with specific geometries were found and possible candidates for the global minimum were determined. All the candidates have small spin multiplicities: 1 or 3 for the neutral clusters, and 2 or 4 for the ionic clusters. Compact (for n > 3, three-dimensional) shapes are generally favored for geometries of the clusters except for some low-profile isomers of the tetramers. For anionic clusters, the most promising global minimum candidates were suggested by simulated photoelectron spectra.