[Co(2,3-tri)(ibn)Cl][ZnCl_(4)]体系一经式异构体的晶体结构及体系异构体的理论计算研究

Crystal Structure and Computational Study on the Isomers of[Co(2,3-tri)(ibn)Cl_(4)]System

用单晶X-射线衍射分析方法解析了犤Co(2,3-tri)(ibn)Cl犦2+(2,3-tri=N-(2-氨基乙基)-1,3-丙二胺,ibn=1,2-二氨基-2-甲基丙烷)体系中一经式异构体(m2-犤Co(2,3-tri)(ibn)Cl犦犤ZnCl4犦)。该晶体属单斜晶系,空间群P21/c,a=11.317(3)?,b=14.931(4)?,c=11.646(3)?,β=101.046(5)°,V=1931.5(8)?3,Dc=1.757g·cm-3,Z=4,F000=1048,R=0.0277,Rw=0.0824。用量子化学从头计算方法,在赝势基组RHF/LANL2DZ的水平上对该体系的十个可能的几何异构体(四个经式异构体和六个面式异构体)进行了结构优化以及各异构体基态能量计算。与两已测晶体的结构参数比较,键长的平均相对偏差约为1.7%,最大相对偏差为3.25%;键角的平均相对偏差约为1%,最大相对偏差为3.83%。比较其基态能量,经式异构体与面式异构体之间以及经式异构体或面式异构体之间无明显的差别。因此,应有较多的几何异构体在合成或反应过程中出现。

The crystal structure of the m2 isomer of [Co(2,3 tri)(ibn)Cl] has been determined (2,3 tri= N (2 Aminoethyl) 1,3 propanediamine, ibn=1,2 diamino 2 methylpropane).Crystal data: monoclinic,P21/c, a=11.317(3)?, b=14.931(4)?, c=11.646(3)?, β= 101.046(5)°, V=1931.5(8)?3, Dc=1.757g·cm-3, Z=4, F000=1048, R=0.0277, Rw=0.0824.A comparison the crystal structures of the m2 and m3 [Co(2,3 tri)(ibn)Cl] complexes with an abinitio computational result(RHF/LANL2DZ optimised structure) shows that the errorsmax are 3.25% in bond lengths and 3.83% in angles, an average errors are 1.7% in bond lengths and 1% in angles; A comparison of ground energies between the isomers suggests that the most geometric isomers in the [Co(2,3 tri)(ibn)Cl]2+ system could be observed due to no significant difference of ground energy among the isomers.