混合团簇Cu12A(A=Fe、Co、Ni)结构及能量特性的密度泛函研究

摘要

Started from the non-compact low symmetric ground-state geometry of Cu13 and four types 13atom high-symmetric (Ih,Oh,D5h,D3h) close-packed structures,by replacing a doping atom in the unequivalent position,the structural and energetic properties of the mixed Cu12A (A=Fe,Co,Ni) clusters are systematically studied by using the density-functional theory.Our results show that:For Cu12A (A=Fe,Co) clusters,each prefers to the Ih-replacing geometry as the ground-state structure,and with replacing the central atom to form a high-symmetric structure,but for Cu12 Ni,its ground-state structure is a non-compact low symmetric one similar to that of Cu13.The stability sequences of those structures from replacing the unequivalent positions of the ground-state geometry of Cu13 are nearly same for all these doping atoms (Fe,Co and Ni),and the center-replacing doping structures are all superior to the surfacereplacing doping structures when replacing the four high-symmetric structures (Fe and Co are all stronger than Ni).There is no obvious isomerism for the ground-state of all these doping clusters.%以Cu13非紧致低对称性基态结构及四种13原子高对称性(Ih、Oh、D5h、D3h)密堆积结构为初始构型,通过不等价位原子替换,利用密度泛函理论系统研究了Cu12A (A=Fe、Co、Ni)混合团簇的结构及能量特性.结果表明:Cu12 A(A=Fe、Co)团簇的基态结构均以Ih替换结构为主,且均倾向于中心位置替代的高对称性结构,而Cu12Ni团簇基态则为与Cu13类似的非紧致低对称性结构；Fe、Co、Ni三者对Cu13基态各不等价位替代结构稳定性序列基本相同,而对四种高对称性结构相应中心替代构型稳定性均高于表面替代构型(且Fe、Co均明显强于Ni)；对各混合团簇基态结构均无明显同分异构现象.