(HCaN_3)_n(n=1～5)团簇结构与性质的密度泛函理论研究  

Density Functional Theory Study on the Structure and Properties of(HCaN_3)_n(n=1～5) Clusters

作　　者：陈玉红[1,2] 张致龙[2] 任宝兴[2] 张材荣[2] 杜瑞[2] 王伟超[2] 

机构地区：[1]兰州理工大学甘肃省有色金属新材料省部共建国家重点实验室,兰州730050 [2]兰州理工大学理学院,兰州730050

出　　处：《化学学报》2011年第11期1293-1300,共8页Acta Chimica Sinica

基　　金：国家自然科学基金(No.10547007);甘肃省自然科学基金(No.1010RJZA042);兰州理工大学博士基金(No.BS10200901)资助项目

摘　　要：利用密度泛函理论在B3LYP/6-311G*水平上对叠氮化合物(HCaN3)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,HCaN3团簇最稳定结构为折线型,(HCaN3)n(n=2～4)团簇最稳定结构为叠氮基端位N原子与Ca原子相互链接形成平面环状结构,(HCaN3)5团簇最稳定结构为立体钟形结构.团簇最稳定结构中金属Ca原子均显示正电性,H原子均显示负电性,叠氮基中间的N原子显示正电性,叠氮基两端的N原子显示负电性,且和Ca原子直接作用的N原子的负电性更强.Ca—N键和Ca—H键为典型的离子键,叠氮基内N原子之间是共价键.最稳定结构的IR光谱主要分为3个部分,其最强振动峰均位于2193～2302 cm-1段,振动模式为叠氮基中N—N键的反对称伸缩振动.叠氮基在团簇和晶体中结构不变,始终以直线型存在,说明金属叠氮化合物团簇可以很好地模拟其晶体的局域成键和局域电荷转移等特性.稳定性分析显示,(HCaN3)3团簇相对于其他团簇更稳定.Possible geometrical structures and relative stability of alkaline-earth metal azido（HCaN3）n（n=1～5） clusters are studied by using the hybrid density functional theory（B3LYP） with 6-311G＊ basis sets.For the most stable isomers of（HCaN3）n（n=1～5） clusters,the bond properties,charge distributions,vibra-tion properties,and stability are analyzed.The calculated results show that the most optimized HCaN3 has linear structure,and the most optimized structure for（HCaN3）n（n=2～4） clusters are the planar ring formed by N atom and the Ca atom at cardinal extremity of nitrogen;the most optimized structure of（HCaN3）5 clusters is three-dimensional bell-shape.The middle Ca atoms of the most optimized structure show positive,H atom show negative.The middle N atoms of azido show positive,the N atoms at both ends of azido show negative,and the N atoms affected with Ca atoms directly show more negative.The IR spectra of the most optimized clusters have three vibration sections,the whole strongest vibration peak lies in 2193～2302 cm-1,and the vibration mode is anti-symmetric stretching vibration of N-N bonds in azido.Stability analysis show that（HCaN3）3 clusters are more stable than other clusters.

关 键 词：(HCaN3)n(n=1~5)团簇 叠氮基 密度泛函理论 结构与性质 

分 类 号：TQ560.1[化学工程—炸药化工]