Which Configuration is More Stable for La2@C80, D3d or D2h? Recomputation with ZORA
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- 作者：Junfeng Zhang ; Ce Hao ; Shenmin Li ; Weihong Mi ; Peng Jin
- 刊名：Journal of Physical Chemistry C
- 出版年：2007
- 出版时间：June 7, 2007
- 年：2007
- 卷：111
- 期：22
- 页码：7862 - 7867
- 全文大小：226K
- 年卷期：v.111,no.22(June 7, 2007)
- ISSN：1932-7455
文摘
Geometry optimization and frequency analysis were performed for a La2@C80 molecule using the Amsterdamdensity functional (ADF) package. The relativistic effects are taken into account by the zero-order regularapproximation (ZORA) basis sets. Interestingly, we found that the D2h configuration is the global minimumin total energy, being about 1 kcal/mol lower than the D3d configuration, which has been recently consideredto be the most stable by Shimotani et al. On the basis of calculations, a new La2 pair motion scenario isproposed, in which the two La ions passing through saddle-point C2h, travel between equivalent D2hconfigurations. The motion of these La ions forms a pentagonal-dodecahedral path just like the pattern of La2MEM charge density in the Ih C80 cage. In addition, the calculated Raman spectrum on low-frequency metal-cage vibrations is also in good agreement with the experimental results.