【摘要】 用密度泛函方法,计算研究1,5-二氨基四唑(DAT)的电子结构及异构化反应机理。在B3LYP/6-311G水平下,对涉及反应各驻点的几何结构、振动频率、自然键轨道、以及零点能(ZPE)进行了计算;用内禀反应坐标理论(IRC)获得反应的最小能量路径(MEP),在耦合簇理论的CCSD(T)方法下计算单点能得到了反应的最小势能曲线;并且用传统过渡态理论(TST)、Eckart隧道校正理论(TST/Eckart)和变分过渡态理论(CVT),计算了200~1000K的反应速率常数。计算结果表明,DAT分子中的N(4)和N(9)易参与金属原子配位,形成一系列以DAT为配体的配位化合物。异构化合成DAT反应为叠氮基关环机理,气态情况下该反应为放热且自发反应,反应活化能较低。更多还原

【Abstract】 The electronic properties of 1,5-diamino-tetrazole(DAT)and isomerization reaction kinetics were studied based on density func- tional theory.The geometry structure,vibration frequencies,natural bonding orbital,and zero point energy(ZPE)of stationary points in- volved in the reaction was calculated at B3LYP/6-311G level of theory.The intrinsic reaction coordinate theory(IRC)was used to obtain the minimum energy path(MEP).The reaction potential energy curve was obtained by calculating the single point energy with CCSD(T)meth- od.The rate constants are evaluated from200 to 1000 K using transition state theory(TST),TST/Eckart and Canonical variational transi- tion state theory(CVT).Results show that N(4)and N(9)in DAT molecule participate easily in coordination with metal atoms,forming a series of coordination compounds.The isomerization reaction for DAT displays azide-cyclization mechanism.At gaseous case,the reaction is exothermic and spontaneous,with lower reaction activation energy.更多还原