화학공학소재연구정보센터
Journal of the American Chemical Society, Vol.122, No.38, 9178-9181, 2000
Synthesis, structure, and bonding of a molecular metalloid Ga-19 cluster anion
A metastable (GaBr)-Br-I solution, prepared by a co-condensation technique, reacts with LiC(SiMe3)(3) to give the metalloid Ga-19 cluster compound [Ga-19(C(SiMe3)(3))(6)][Li2Br(THF)(6)] (1). The central Ga atom of 1 shows a 6 + 6 coordination to the 12 non-ligand-bearing Ga atoms. Due to the high symmetry of the environment of this Ga atom, a sharp Ga-71 NMR signal at delta Ga-71 = -134 was observed in solution. The experimentally found NMR signal of the topologically "metallic" Ga atom is compared to the results of DFT calculations of different Ga19R6- species as well as to those of the naked Ga-13(-) cluster. On these grounds it is shown that the electronic behavior of naked clusters is completely different from that of ligand-stabilized metalloid clusters.