中文摘要：

应用密度泛函理论方法研究了8种新型含氮杂环卡宾单元的硅烯，在M06-2x／6-311＋G（d，P）水平上计算了它们的单重态及三重态的结构，在QCISD／6-311 ＋ ＋G（d，P）水平上计算了单点能量．结果表明，这些硅烯的三重态能量比单重态能量低，基态为三重态．引进氮杂环卡宾骨架能够提高三重态硅烯的稳定性．

英文摘要：

Eight new silylenes containing N-heterocyclic carbenic （NHC） unit are investigated by density functional theory method. For these silylenes, the geometries of singlet-and triplet-states are optimized at M06 - 2x/6 - 311 ＋ G （d, p） level, and then the single-point energies are calculated at QCISD/6 -311 ＋ ＋ G （d, p） level. The re- suits indicate that the energies for triplet states are lower than those for singlet states. Therefore, the ground states of these silylenes are triplet. The use of an NHC skeleton can increase the stability of the triplet states.