AMT异构体互变机理的理论研究

A Theoritical Study on the Mechanism of Interconversion of 2-amino-5-mercapto1,3,4-thiadiazole Isomers

用密度泛函理论(DFT)的B3LYP/6-311G(d,p)和Mller-Plesset微扰理论的MP2/6-31G(d)方法,优化了AMT(2-氨基-5-巯基-1,3,4-噻二唑)各种异构体和过渡态结构的几何构型,并对它们的电子结构、振动光谱和化学键性质进行了研究.还研究了AMT异构体的互变机理,提出了AMT异构体abcda的循环式互变途径.进一步完成了对AMT异构体成键方式的自然键轨道(NBO)分析.

The optimized geometries, infrared spectra, electron structure and bonding behavior of the isomers and transition states of 2-amino-5-mercapto-1, 3, 4-thiadiazole are studied by density functional theory(DFT) and second-order Moller-Plesset perturbation theory at B3LYP/6-311G(d, p)and MP2/6-31G(d) levels. The mechanisms of interconversion of 2-amino-5-mercapto-1, 3, 4-thiadiazole(AMT) isomers are studied, and a mechanism of cyclic interconversion of AMT isomers areversible arrowbreversible arrowcreversible arrowdreversible arrowa is proposed. The atom charges, bond order and hybrids orbitals of the AMT isomers are discussed using the natural bond orbital(NBO) analysis.