过硫化氢分子及过硫化氢离子低电子态的理论研究

Theoretical Studies on Low-lying states of Hydrogen Persulfide Molecule and the Corresponding Cation

为了丰富过硫化氢分子和过硫化氢一价阳离子的电子基态和激发态的信息,采用量子化学中密度泛函理论的B3LYP方法,使用6-311++g(3df,3pd)基组,对其进行了研究。计算得到了过硫化氢分子HSSH基态和过硫化氢离子HSSH+基态及激发态的平衡构型、光谱常数、总能量和零点振动能。计算表明:过硫化氢中性分子是长对称陀螺分子,二面角为90.66°,具有C_2对称性,而过硫化氢离子HSSH+有顺式(二面角为0°)和反式(二面角为180°)两种稳定的异构体,反式结构基态能量比顺式结构基态能量低0.129 e V;此外计算还得到了过硫化氢离子HSSH+两种异构体的基态和激发态的电子结构。

In order to enrich the information of the electronic ground states and excited states of hydrogen persulfide molecule HSSH and hydrogen persulfide monovalent cation HSSH+the B3LYP calculation of density functional theory with the 6-311++g(3df,3pd)basis set level was used to investigate them.The equilibrium configurations,spectroscopic constants,total energies and zero point vibration energies of HSSH in the ground state and HSSH+in the ground state and excited states are obtained.The calculation show that HSSH is a long symmetric gyroscope molecule with C 2 symmetry and the dihedral angle is 90.66°,whereas HSSH+has two stable isomers,cis-HSSH+(the dihedral angle 0°)and trans-HSSH+(the dihedral angle 180°).The electron energy of the trans-HSSH+isomer is 0.129 eV lower than that of the cis-HSSH+isomer.In addition,the ground-state and excited state electronic structures of HSSH+have also been calculated.