Collisional destruction of anionic carbon and silicon clusters by helium, neon, and argon atoms at intermediate velocities - art. no. 032701

We measured the total destruction cross sections of small X-n(-) clusters ( X = Si and C; n = 2, 3, and 4) in noble, s targets (Y = He, Ne, and Ar), wi th relative velocities upsilon in the 0.10-0.95 a.u interval for silicon, a nd in the 0.20-1.20 a.u. interval for carbon. The measured values increase monotonically with target and projectile sizes, as expected on a geometrica l basis. In particular the dependence of the cross sections on n. is linear for carbon clusters, agreeing with a quantitative model based on the linea r structure of these clusters. Ratios of the measured cross sections for th e several X-n(-) clusters, sigma (Ne)(X,n)(upsilon)/sigma (He)(X,n)(upsilon ), sigma (Ar)(X,n)(upsilon)/sigma (He)(X,n)(upsilon), and sigma (Ar)(X,n)(u psilon)/sigma (Ne)(X,n)(upsilon) were verified to fall into universal curve s, i.e., each cross section is the product of target- and projectile-depend ent factors.