文摘
Silicon clusters mixed with a transition metal atom, MSin, were generated by a double-laser vaporizationmethod, and the electronic and geometric stabilities for the resulting clusters with transition metal encapsulatedby silicon were examined experimentally. By means of a systematic doping with transition metal atoms ofgroups 3, 4, and 5 (M = Sc, Y, Lu, Ti, Zr, Hf, V, Nb, and Ta), followed by changes of charge states, weexplored the use of an electronic closing of a silicon caged cluster and variations in its cavity size to facilitatemetal-atom encapsulation. Results obtained by mass spectrometry, anion photoelectron spectroscopy, andadsorption reactivity toward H2O show that the neutral cluster doped with a group 4 atom features an electronicand a geometric closing at n = 16. The MSi16 cluster with a group 4 atom undergoes an electronic changein (i) the number of valence electrons when the metal atom is substituted by the neighboring metals with agroup 3 or 5 atom and in (ii) atomic radii with the substitution of the same group elements of Zr and Hf. Thereactivity of a halogen atom with the MSi16 clusters reveals that VSi16F forms a superatom complex withionic bonding.