高等学校化学学报2013，Vol.34Issue(2)：455-461,7.DOI:10.7503/cjcu20120363
NiTi过渡金属团簇的结构和芳香性的理论研究
Theoretical Studies on Structures and Aromaticity of NiTi Clusters
摘要
Abstract
The structures and aromaticity of Ni4, [ Ni4 ]2+ and [ Ni4 ]2- , Ni4Ti2, [ Ni4Ti2 ]2+ and [ Ni4Ti2 ]2-, Ni4Ti4, [Ni4Ti4]2+ and [Ni4Ti4]2- were studied at the B3PW91/6-311+G(d) basis level with density functional theory ( DFT). Introduction of Ti atoms to both sides of Ni4 ring brings about stable conformations Ni4Ti2 (D4h), [Ni4Ti2]2+(D4h), [Ni4Ti2]2-(D4h) and Ni4Ti4(D2h) with square-planar ring of Ni4. Nucleus-independent chemical shifts(NICS) calculations show positive NICS value in Ni4Ti2(D4h) and Ni4Ti4(D2h) , negative NICS value in [ Ni4Ti2 ]2+ (D4h) , and more negative NICS value in [ Ni4Ti2 ]2-(D4h). Analysis results show that the formation of diamagnetic circulation involving s and d orbitals is the main cause for the relatively strong aromaticity of [ Ni4Ti2 ]2+ ( D4h) and [ Ni4Ti2 ]2- ( D4h ). In such case, Ti atoms provide dz2 and s orbitals, and Ni atoms form square with their dz2 and dx2_y2 orbitals, with which a spherical electron current forms in [ Ni4Ti2]2+(D4h) and [Ni4Ti2]2-(D4h) with conspicuous π electron current.关键词
密度泛函理论/芳香性/核无关化学位移/NiTi形状记忆合金Key words
Density functional theory/ Aromaticity/ Nucleus-independent chemical shift/ NiTi shape memory alloy分类
化学化工引用本文复制引用
时圣刚,封继康,田维全,刘子忠,李伟奇,崔艳红..NiTi过渡金属团簇的结构和芳香性的理论研究[J].高等学校化学学报,2013,34(2):455-461,7.基金项目
国家自然科学基金(批准号:20473031)资助. （批准号:20473031）
