对含Si的ptC单元CAl2Si2进行了夹心组装的理论研究, 发现当CAl2Si2与碱金属及碱土金属(M=Li, Na, K, Be , Mg, Ca)组装成夹心化合物时, 由于CAl2Si2之间强烈的熔合作用, 不能采取传统的“同夹板夹心”方式, 即[(CAl2Si2)M(CAl2Si2)]q+的形式, 而新的“杂夹板夹心”形式([CpM(CAl2Si2)]q+)更适合CAl2Si2的组装. 计算结果表明, 在组装过程中, CAl2Si2的电子和结构特征得到很好的保持. 因此, 平面四配位碳单元CAl2Si2可以作为“建筑单元”构建大尺寸含平面中心碳的化合物.
One of the focuses of molecular science is the theoretical and experimental investigations on the pentatomic planar coordinated carbon(ptC) molecules. This paper for the first time reported the design of sandwich-like compounds based on a Si-containing ptC unit CAl2Si2. We found that due to the strong fusion interaction between CAl2Si2 decks, the assembly of CAl2Si2 with the alkali and alkaline earth metals(M=Li, Na, K, Be, Mg, Ca)in form of the traditional “homo-deckered sandwich” scheme to form [(CAl2Si2)M(CAl2Si2)]q+ is unstable. Instead, our recently proposed “hetero-decked sandwich” scheme can be effectively applied to CAl2Si2 to form [CpM(CAl2Si2)]q+). Both the “hetero-decked sandwich” and the ionic interaction play important roles in the assembly and stabilization of CAl2Si2. During the assembly, the electronic and structural features of CAl2Si2 are well kept. Thus, the ptC molecule CAl2Si2 can act as a “building block” to construct large-scale compounds that contain planar coordinated carbon centers.