摘要
Structural stability and Si-substitution pattern in fullerene cage of C_(60−n)Sin are thoroughly investigated by integrating density functional calculations with a colorbond graph(CBG)model.We find that the parameterized CBG model with genetic algorithms can efficiently scan the large configuration space of alloy and therefore identify the low-energy region within the first-principles accuracy.Low-energy(stable)structures of C_(60−n)Sin in carbon-rich region(1≤n≤30)were identified and the silicon atoms are found to tend to aggregate in the fullerene cage.The mixing energy of these low-energy structures is ~35 meV/atom and insensitive to the Si concentration.We expect that these alloy fullerene cages can be synthesized experimentally at elevated temperatures.
基金
supported from Academia Sinica and Nanyang Technological University.