【摘要】 用从头计算方法研究了B₁₂C_xN_12-x（x=2,4）笼的几何和电子结构.从B₁₂N₁₂中用C原子替换N原子得到B₁₂C_xN_12-x,这样取代的结构中只含B—C和B—N键.在稳定结构中,C原子在四元环上,形成了B₂C₂和B₂N₂环.B₁₂C₂N₁₀的HOMO主要由C和N的2p轨道组成,LUMO位于-3.6eV处,主要由C的2p轨道组成.B₁₂C₄N₈的HOMO也主要由C和N的2p轨道组成,LUMO位于-4.1eV处,主要由C的2p轨道组成.在B₁₂N₁₂,B₁₂C₂N₁₀和B₁₂C₄N₈中B原子上的电荷约为1.17e,C原子上的电荷为-0.75e.B₁₂N₁₂,B₁₂C₂N₁₀和B₁₂C₄N₈的能带隙分别为6.84eV,3.50eV和2.82eV.更多还原

【Abstract】 The geometry and electronic structure of B₁₂C_xN_12-x（x=2,4）cages are studied by ab initio calculations.The structure is generated by replacing N with C in the B₁₂N₁₂ cage to ensure only B—C and B—N bonds are formed.C atoms in the tetragonal rings of the stable structure is formed B₂C₂ and B₂N₂ squares.The HOMO of B₁₂C₂N₁₀ is mainly formed by 2 p of C and N,and LUMO is located at-3.6 eV,mainly formed by C2 p orbitals.The HOMO of B₁₂C₄N₈ is also formed by 2 p of C and N,LUMO is located at-4.1 eV,mainly formed by 2 p of C.The natural charge on N and C is about 1.17 eand-0.75 ein B₁₂N₁₂,B₁₂C₂N₁₀ and B₁₂C₄N₈.The energy gap of B12 N12,B12 C2 N10 and B₁₂C₄N₈ is 6.84 eV,3.50 eV and 2.82 eV respectively.更多还原