| Abstract
| - 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.
|
