SiCS分子结构及其稳定性的理论研究

Theoretical Study on Structures and Stabilities of Molecule SiCS

采用 DFT,QCISD及 CCSD( T)方法对单重态、三重态 Si CS的分子体系势能面进行理论计算 ,在QCISD/6-3 1 1 G( d)水平上得到由 3个过渡态连接的 5个稳定构型 .经动力学及热力学分析均是稳定的三重态线型分子 Si CS( 31 )、单重态线型分子 Si CS( 1 1 )以及单重态的环状分子 c Si CS( 1 2 )

The singlet and triplet PESs of SiCS were investigated by the DFT, QCISD and CCSD(T) levels. At the QCISD level, it is shown that total five minimum isomers are connected by 3 transitional states. The global minima is a linear triplet isomer SiCS 31 followed by a second low-lying singlet linear SiCS( 11) and a cyclic isomer cSiCS( 12).