Min Kil Sik, Miller Joel S
Department of Chemistry, University of Utah, 315 S. 1400 E. RM 2124, Salt Lake City, UT 84112-0850, USA.
Dalton Trans. 2006 May 28(20):2463-7. doi: 10.1039/b516198c. Epub 2006 Mar 6.
The reaction of (NBu4)3[V(III)(ox)3] (1, ox = oxalate) and M(II) (M = Fe, Co, Ni, Cu) ions in MeCN, leads to the isolation of V-based coordination polymers of [N(n-Bu)4][Fe(II)V(II)I(ox)3].0.30[N(n-Bu)4] (2), [N(n-Bu)4][Co(II)V(III)(ox)3].0.75[N(n-Bu)4] (3), [N(n-Bu)4][Ni(II)V(III)(ox)3].0.20[N(n-Bu)4].0.20MeCN (4), and [N(n-Bu)4]Cu(II)V(III)(ox)22 (5) composition. Due to the lability of [V(III)(ox)3]3- to dissociate ox2-, these compounds cannot be prepared from aqueous media. 5 is best described as [N(n-Bu)4]V(III)Cu(II)(ox)22, and 2, 3, 4, and 5 are proposed to have a layered (2-D) motif for the MM(ox)x (x = 2, 3) extended framework. The [V(III)Cu(II)(ox)2] composition of 5 is reported for the first time for a bimetallic oxalate. 2 shows a weak antiferromagnetic interaction between Fe(II), S = 2 and V(III), S = 1 ions (theta = -9.4 K) within the 2-D layers. 3 and 5 do not magnetically order above 2 K. 4 magnetically order as ferromagnets below 2.55 K [taken as the onset of magnetization in chi''(T)], and has a glass transition temperature (chi'(max) at 1000 Hz) at 2.26 K.
（四丁基铵）₃[V(III)(草酸根)₃]（1，草酸根 = oxalate）与M(II)（M = Fe、Co、Ni、Cu）离子在乙腈中反应，得到了组成分别为[N(n - Bu)₄][Fe(II)V(II)I(草酸根)₃]·0.30[N(n - Bu)₄]（2）、[N(n - Bu)₄][Co(II)V(III)(草酸根)₃]·0.75[N(n - Bu)₄]（3）、[N(n - Bu)₄][Ni(II)V(III)(草酸根)₃]·0.20[N(n - Bu)₄]·0.20乙腈（4）和[N(n - Bu)₄]Cu(II)V(III)(草酸根)₂₂（5）的钒基配位聚合物。由于[V(III)(草酸根)₃]³⁻易解离草酸根²⁻，这些化合物无法在水介质中制备。5最好描述为[N(n - Bu)₄]V(III)Cu(II)(草酸根)₂₂，并且推测2、3、4和5的MM(草酸根)ₓ（x = 2, 3）扩展框架具有层状（二维）结构单元。5的[V(III)Cu(II)(草酸根)₂]组成是首次在双金属草酸盐中报道。2在二维层内的Fe(II)，S = 2和V(III)，S = 1离子之间表现出弱反铁磁相互作用（θ = -9.4 K）。3和5在2 K以上没有磁有序。4在2.55 K以下（取为χ″(T)中磁化的起始温度）磁有序为铁磁体，并且在2.26 K有一个玻璃化转变温度（1000 Hz时的χ′(最大值)）。
