C_nAl_m^+(n=1～12,m=1,2)团簇几何结构特征与稳定性的量子化学研究  

Quantum Chemical Study on Structural Characteristics and Stability of C_nAl_m^+ (n=1～12, m=1, 2) Clusters

作　　者：马文瑾[1] 宋翔[1] 张献明[1] 武海顺[1] 

机构地区：[1]山西师范大学化学与材料科学学院,临汾041004

出　　处：《化学学报》2010年第19期1942-1950,共9页Acta Chimica Sinica

基　　金：国家自然科学基金(Nos.20771069;20871077);山西省高校科技(No.20091015)资助项目

摘　　要：采用密度泛函理论(DFT)的B3LYP方法,在6-311++G**水平上对CnAlm+(n=1～12,m=1,2)团簇的几何和电子结构进行了理论计算,讨论了混合团簇的结构与成键特征,以及振动频率与电荷转移.结果表明,CnAl+团簇的基态结构分别为Al原子与Cn链端基配位形成的直线或折线状结构,以及Al原子与Cn环上1个C原子端位相连或打开Cn环与2个C原子相连形成的环状结构;分子总的平均键长随着n的增大逐渐趋于定值0.138nm.CnAl+2团簇基态结构可以看作是两个较小的Cn/2Al+分子碎片通过端位C原子相互结合形成CcoreAlshell的直线或顺式与反式折线状结构;分子总的平均键长随着n的增大逐渐趋于定值0.141nm.通过对基态结构的能量分析,得到了CnAl+和CnAl+2团簇的稳定性信息.The geometrical and electronic properties of C n Al＋m （n=1～12, m=1, 2） clusters have been investigated at the B3LYP/6-311＋＋G＊＊ level. The structural and bongding characteristics, frequency and charge transfers of these doped clusters have been discussed. The calculations show that the ground state of CnAl＋ clusters was linear or polyline structures with terminal aluminum atom, and an aluminum atom inserted to a Cn ring form a new ring structure or with an aluminum atom bonded to one side of a monocyclic Cn ring. With the increasing of n, the total average bond length of the species is close to 0.138 nm gradually. The ground state structure of C n Al＋2 clusters is linear or polyline （cis or trans） CcoreAlshell structure, which be formed by the combination of the terminal C atoms of two smaller Cn/2Al＋ fragments. The overall average bond length of this species tends to be the value of 0.141 nm with increasing cluster size. Through the energy analysis of the ground state, we have obtained the stability information of C n Al＋m clusters.

关 键 词：CnAlm+团簇 基态结构 密度泛函理论 稳定性 

分 类 号：O641.1[理学—物理化学]