Electronic and Geometric Stabilities of Clusters with Transition Metal Encapsulated by Silicon

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• 作者：Kiichirou Koyasu ; Junko Atobe ; Minoru Akutsu ; Masaaki Mitsui ; Atsushi Nakajima
• 刊名：Journal of Physical Chemistry A
• 出版年：2007
• 出版时间：January 11, 2007
• 年：2007
• 卷：111
• 期：1
• 页码：42 - 49
• 全文大小：320K
• 年卷期：v.111,no.1(January 11, 2007)
• ISSN：1520-5215

文摘

Silicon clusters mixed with a transition metal atom, MSi_n, 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.