CRYSTAL STRUCTURES AND TRIBOLUMINESCENT ACTIVITIES OF SAMARIUM(III) COMPLEXES

Abstract

The triboluminescence spectra and crystal structures of 1,2-dimethylpyridinium tetrakis(2-thenoyltrifluoroacetonato)samarium(III) (1) and 1,2,6-trimethylpyridinium tetrakis(2-thenoyltrifluoroacetonato)samarium(III) (2) were determined. The triboluminescent maximums are similar to those of the photoluminescence. Complex 1 is centrosymmetric and the triboluminescent emission may correlate with the disorder of all S atoms, all CF₃ groups and the cation. The triboluminescent activity of complex 2 may correlate with its noncentrosymmetric space group. Complex 1 crystallizes in the monoclinic space group P2₁/a with cell parameters a = 19.874(2) Å, b = 22.922(2)Å, c = 21.188(1)Å, β = 108.126(6)°, V = 9173(1)ų; Z = 8; R = 0.0758 and R_w = 0.1315. Complex 2 crystallizes in the monoclinic space group Pn with cell parameters a = 11.2808(6)Å, b = 11.0199(5)Å c c = 18.4336(9)Å, β = 108.126(6)° V = 2285.28(19)ų; Z = 4; R = 0.0347 and R_w = 0.0900. All the structures were refined by full-matrix least squares methods.     

Solubility, dissociation and complexation with Nd(III) and Th(IV) of oxine, thenoyltrifluoroacetone and 1,10-phenanthroline in 5.0 m NaCl

Equilibria in the system of Nd(III) and Th(IV) with 8-hydroxyquinoline (oxine), thenoyltrifluoroacetone (HTTA) and 1,10-phenanthroline (phen) in 5.0 m NaCl solution have been investigated by spectroscopy and potentiometry. The solubility and deprotonation constants of the three organics were measured to be: pK_s = 3.09 ± 0.01, pK_a1 = 5.82 ±0.02, pK_a2= 10.00 ±0.01 for oxine; pK_s = 2.49 ± 0.01, pK_a1 = 6.47 ±0.03 for HTTA; pK_s = 2.86 ± 0.02, pK_a2 = 5.82 ± 0.05 for phen. The stabilities of the corresponding metal complexes are in the order M(oxine) > M(TTA) > M(phen), where M = Nd(III), Th(IV). For all three organic ligands, the Th(IV) complexation is stronger than that of Nd(III).     

固态配合物Cr(Ⅲ)(PMBP)_3,Cr(Ⅲ)(TTA)_3,Fe(Ⅲ)(PMBP)_3和Fe(Ⅱ)(PMBP)_2的合成,燃烧热及热分析研究

合成了配合物Fe(Ⅲ)(PMBP)_3,Fe(Ⅱ)(PMBP)_2,Cr(Ⅲ)(PMBP)_3和Cr(Ⅲ)(TTA)_3。用弹式量热计测定了燃烧热。用TG-DTA和DSC法确定了放热峰之一的活化能,反应热和反应级数。     

RE（Ⅲ）—HTTA—TPhPO协萃体系的研究

本文采用两相滴定法研究HTTA-TPhPO对五种三价稀土离子(Pr、Nd、Sm、Gd、Tm)的协同萃取机理.在15、20、25℃三个温度下,测定了各萃合物的分子组成及稳定常数,进而得出协萃反应的热力学函数.并与类似的协萃体系作了比较.     

人工神经网络用于Ln3+的萃合及协萃体系稳定常数的关联和预测

研究了影响Ln^3 离子的萃合及协萃合物稳定性的有关因素。以Ln^3 离子的半径、电负性，4f电子排布周期因子q(本文自定义）以及基态L值等为参数，使用函数连接型神经网络（FLN），对Ln^3 的HTTA萃合物，HTTA－P350协萃合物及HTTA－TPB协萃合物的稳定常数分别进行了非线性关联和预测，获得了好的结果。     

N，N＇－二（乙酰芳香环）－穴醚［2，2］的合成

Ｎ，Ｎ＇－二（乙酰芳香环）－穴醚［２，２］的合成余江，许振华，徐光宪（北京大学化学与分子工程学院，稀土材料化学及应用国家重点实验室，北京，１００８７１）关键词大环，穴醚［２，２］，ＨＴＴＡ穴醚（Ｃｒｙｐｔａｎｄ）是含有Ｏ及Ｎ和Ｓ等杂原子的多聚大环化合...     

N-乙基吡啶四(α-噻吩甲酰三氟丙酮)合铕的合成和晶体结构

合成了标题络合物的晶体,在四圆衍射仪上测得其晶体结构。晶体Eu(TTA)_4Epy属三斜晶系,P(?)空间群,中心离子Eu(Ⅲ)和4个TTA~-通过8个氧原子螯合配位,Epy为外界阳离子。晶胞参数如下:a=12.437(5),b=17.816(3),c=10,706(3)(?),α=90.92(2)°,β=102.01(3)°,γ=87.10(2)°,Z=2。此外,还对该化合物的热稳定性、红外及紫外可见光谱以及荧光性质进行了研究。