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用第一性原理方法对VC(0 0 1)清洁表面的构型和电子结构进行了详细研究 ,与TiC(0 0 1)面类似 ,VC(0 0 1)面弛豫后形成表面皱褶 ,其表层V原子和C原子分别朝体相和真空方向移动 .能带计算结果表明 ,过渡金属碳化物(0 0 1)面的能带结构符合刚性带理论模型 .对于VC(0 0 1)面 ,表面态主要处在 - 3 0eV附近 ,其主要成分为表层C原子的 2pz轨道 .此外 ,以表层V原子的 3d轨道成分为主的表面态出现在费米能级附近 ,由于这些表面态以表面法线方向的轨道 (3d2 z和 3dxz dyz)为主要成分 ,因此在表面反应中将起到重要作用 ,从而体现出与TiC(0 0 1)面不同的反应性质 .
The structure and electronic structure of the VC (001) clean surface have been studied in detail using the first principle method. Like the TiC (001) plane, the VC (001) surface relaxes to form surface folds , The V atom and the C atom of the surface migrate toward the bulk and the vacuum, respectively.The energy band calculation results show that the band structure of the (0 0 1) plane of the transition metal carbides complies with the theoretical model of the rigid band.For VC (0 0 1) The surface state is mainly in the vicinity of 3eV and the main component is the 2pz orbital of the C atom in the surface layer. In addition, the surface states dominated by the 3d orbital elements of surface V atoms appear near the Fermi level, The surface normal direction of the track (3d2z and 3dxzdyz) as the main component, and therefore plays an important role in the surface reaction, which reflects the reaction with the TiC (001) different properties.