用密度泛函理论（DFT）,在BP86/6-311＋＋g（d,p）水平上对V2,VH和V2H进行了理论研究.得到该系列分子的基态电子态分别为：V2（3^△∑g）,VH（X ^5△V2H（2 B1）,V2H分子的基态稳定构型具有C2v对称性.用Murrell-Sorbie势能函数对V2和VH分子的扫描势能点进行了拟合,其扫描点都与四参数Murrell-Sorbie函数拟合曲线符合很好,在此基础上推导出了它们的光谱数据和力常数.用多体项展开理论导出了V2H分子的解析势能函数,在固定键角∠VHV=58.7°时,RH-V=0.1790 nm处存在一个势阱,深度为7.26 eV,表示在该处容易形成稳定的V2H分子.“,”The molecular structures of ground state V2,VH and V2H have been calculated on the level of BP86/6-311＋＋g（d,p） using DFT method.The results show that the electronic state of the ground states of the molecules respectively are V2（3^∑）,VH（X^5△） and V2H（2^B1）.The stable structure of V2H molecule is of C2v symmetry.Each potential energy curve got via scanning the single point energy of VH and V2 matches well with that fitted with the four-parameter Murrell-Sorbie Function,according to which spectral data and force constants are deduced.The whole special analytical potential energy function of V2H is de-rived from the many-body expansion theory.And it exists a potential trap of 7.26 eV depth at 0.1790 nm（RH-V） when fastening the VHV angle,which suggests that a stable V2H molecule could be formed easily.