Magic Number Behaviour and Structures of Silicon Dioxide-Based Clusters
SHAO He-Zhu, LI Yu-Fen, ZHUANG Jun
Department of Optical Science and Engineering, State Key Joint Laboratory for Materials Modification by Laser, Ion and Electron Beams, Fudan University, Shanghai 200433
Magic Number Behaviour and Structures of Silicon Dioxide-Based Clusters
SHAO He-Zhu;LI Yu-Fen;ZHUANG Jun
Department of Optical Science and Engineering, State Key Joint Laboratory for Materials Modification by Laser, Ion and Electron Beams, Fudan University, Shanghai 200433
Abstract： The lowest energy structures of (SiO2)nO2 cluster skeletons with size from n=2 to 12 is investigated theoretically by genetic algorithm. The calculations based on the Tsuneyuki--Tsukada--Aoki--Matsui (TTAM) and Flikkema--Bromley (FB) potentials give the same result: n=4 and n=8 are the magic numbers in the virtual (SiO2)nO2 cluster sequence. This conclusion is in agreement with the experimental observation on the [(SiO2)nO2H3]- cluster sequence. The comparison of the present results with those from the density-functional-theory calculations on (SiO2)nO2H4 shows that addition of H atoms to the O terminals of (SiO2)nO2 clusters to form the complex (SiO2)nO2H4 clusters has only minor influence on the relative energies and the structures of different isomers. This means that the magic behaviour of the clusters [(SiO2)nO2H3]- (n=4, 8) observed in our previous experiment is originated from the stability of the cluster skeletons (SiO2)n02 (n=4, 8).
2006, Vol. 23 
