二DMF-μ-四酞酰替对甲苯胺合二铜的晶体结构和电子结构的研究

本文报导了的晶体结构。晶体属三斜晶系, 空间群P_1, 晶胞参数: a=1.0761(2), b=1.3930(4), c=1.5117(4) nm; α=114.74(2)°,β=101.82(2)°,γ=95.85(2)°; Z=1。标题化合物为四羧基桥的双核铜(II)簇合物, DMF占据端基位置。Cu-Cu距离0.2635(2) nm, 有微弱成键作用。SCC-EHMO计算表明前线轨道38A_g, 37B_u, 21A_u和20B_g能级相当接近, 化合物为顺磁性, μ(eff)=1.82B.M., 根据顺磁谱出现的由三组峰组成的一套谱, 其中在低场的一组峰分裂7条超精细结构峰, 判断化合物顺磁性应是占据38A_g, 和37B_u分子轨道上未配对电子的贡献。Cu-Cu的成键和反键的σ, π和δ型轨道都填满电子, 因此对成键不起作用。Cu-Cu之间的微弱成键作用, 主要是通过铜与羧基桥原子形成的非定域键的34B_u和18A_u分子轨道的贡献。

THE CRYSTAL AND ELECTRONIC STRUCTURE OF [Cu2 (C6H4 (COO) (CONHC6H4CH3))4 (DMF)2]·4DMF

The title compound is synthesized and crystallized in the monoclinic system; space group P1, a=1.0761(2), b=1.3930(4), c=1.5117(2) nm; α=114.74(2)°, β=101.82(2)°, γ=95.85(2)°; Z=1. The final R factor is 0.076 based on 2083 reflections with I≥3σ(I). In the title compound, coppcr(II) ions are bridged in pairs by four acetate groups with two DMF molecules occupying the terminal positions. The copper(II) ions are 0.020 nm out of the plane of the four oxygen atoms. The distance between the two copper(II) ions is 0.2635 nm which is only slightly greater than 0.255 nm, the interatomic distance in metal copper. A weak bonding existed between the two atoms.SCC-EHMO calculation...