论文部分内容阅读
利用密度泛函理论在B3LYP/6-311G*水平上对碱土金属叠氮化合物(CaN6)n(n=1～5)团簇各种可能构型进行了几何优化,预测了各团簇的最稳定结构.并对最稳定结构的成键特性、电荷分布、振动特性及稳定性进行理论研究.结果表明,叠氮化合物中叠氮基以直线型存在,CaN6团簇的最稳定结构为线型结构,(CaN6)n(n=2～5)团簇首先由两个叠氮基与两个Ca原子构成一个近似菱形,再由菱形相互垂直形成链状最稳定结构;叠氮基中间的N原子显示正电性,两端的N原子显示负电性,且与Ca直接作用的N原子负电性更强,金属Ca原子和N原子之间形成很强的离子键;(CaN6)n(n=1～5)团簇最稳定结构的IR光谱分为4个部分,其最强振动峰均位于2195～2280cm-1,振动模式为叠氮基中N—N键的反对称伸缩振动;稳定性分析显示,(CaN6)3和(CaN6)5团簇相对于其他团簇较为稳定.
The geometrical optimization of various possible configurations of alkaline earth metal azide (CaN6) n (n = 1 ~ 5) clusters at B3LYP / 6-311G * level was carried out by using density functional theory Stable structure, theoretical study on bond formation, charge distribution, vibration characteristics and stability of the most stable structure.The results show that the azide in azide is linear, and the stablest structure of CaN6 cluster is linear (CaN6) n (n = 2 ~ 5) clusters firstly form an approximate rhombus with two azides and two Ca atoms, and then the diamonds are perpendicular to each other to form the most stable chain structure; the N Atoms show positive charge, N atoms at both ends show negative charge, and N atom which directly interacts with Ca has stronger negative charge. CaN6 n (n = 1 ~ 5) The most stable structure of the IR spectra of the cluster is divided into four parts, the strongest vibration peak at 2195 ~ 2280cm-1, the vibration mode for the azido N-N bond anti-symmetric stretching vibration; stability analysis Shows that (CaN6) 3 and (CaN6) 5 clusters are more stable relative to other clusters.