Electronegativity force of cations and thermal decomposition of complex fluorides
摘要:
The thermal decomposition of anhydrous fluoroborates MBF(4) (M=Li, Na, K, Rb, Cs) and M(BF4)2 (M=Ca, Sr, Ba) was investigated. The decomposition proceeds according to a simple acid-base mechanism with evolution of BF3. The influence of the acidity of cationic counter-ions, expressed by the electronegativity force on the course of thermal decomposition was estimated quantitatively.
Click synthesis and complexation properties of a new unsymmetrical macrocycle bearing 1,4-dioxabenzene and triazole units
摘要:
We report herein synthesis of a new triazole-based unsymmetrical macrocycle through Copper(I) catalyzed Alkyne - Azide Cycloadditon (CuAAC), using a copper(I)-N-heterocyclic carbene complex as catalyst. The obtained macrocycle was characterized by NMR spectroscopy and High Resolution Mass Spectrometry (HRMS). The complexation ability of the macrocycle towards various cations as well as its selectivity for a particular metal-ion was investigated by HRMS experiments.
Structural and mechanistic studies on ion insertion into the molecular box {[CpCo(CN)3]4[Cp*Ru]4}
作者:Maya Ramesh、Thomas B. Rauchfuss
DOI:10.1016/j.jorganchem.2004.02.028
日期:2004.4
The molecular box [CpCo(CN)3]4[Cp*Ru]4 (Co4Ru4) reacts readily with a variety of monocations to form M⊂Co4Ru4+ (M=K+, Cs+, Rb+). Ion competition experiments, monitored by ESI-MS, show that the molecular box binds the smaller K+ more rapidly than Cs+, but that thermodynamically Co4Ru4 prefers the larger ion. The rates of ion-insertion for K+ and Cs+ into Co4Ru4 were found to qualitatively follow second
分子盒[CpCo(CN)3 ] 4的[Cp *茹] 4(共4的Ru 4)反应容易地与多种单阳离子的形成M⊂Co 4的Ru 4 +(M = K +,铯+,RB +)。通过ESI-MS监测的离子竞争实验表明,分子盒结合较小的K +的速度比Cs +更快,但热力学上Co 4 Ru 4更喜欢较大的离子。离子将K +和Cs +插入Co 4 Ru 4的速率被发现定性地遵循二阶动力学,其中K +,300 M -1 s -1和Cs +,36 M -1 s -1。比率k K / k Cs定性地匹配离子竞争实验的ESI-MS结果。发现离子插入Co 4 Ru 4的速率取决于抗衡阴离子。特别是,RbBF 4的Co反应4汝4慢于做RbOTf。较慢的速率使我们能够建立二阶动力学。1 H NMR研究表明Co的Cp信号4茹4是在进入离子,例如,Rb的存在非常敏感+,而对于Rb⊂Co相应CP信号4的Ru 4 +是不敏感的Rb的存在+。的分子结构[CO
Cation-Tuned Synthesis of Fluorooxoborates: Towards Optimal Deep-Ultraviolet Nonlinear Optical Materials
作者:Ying Wang、Bingbing Zhang、Zhihua Yang、Shilie Pan
DOI:10.1002/anie.201712168
日期:2018.2.19
The development of new nonlinear optical (NLO) materials for deep‐ultraviolet (DUV) applications is in great demand. However, the synthesis of an ideal DUV NLO crystal is a serious challenge. Herein, three new alkali‐metal fluorooxoborates, AB4O6F (A=K, Rb, and Cs, and a mixed cation between two of them), were successfully synthesized by cation regulation. It is found that all reported compounds exhibit
迫切需要开发用于深紫外线(DUV)应用的新型非线性光学(NLO)材料。但是,理想的DUV NLO晶体的合成是一个严峻的挑战。在这里,通过阳离子调节成功地合成了三种新的碱金属氟硼酸盐,AB 4 O 6 F(A = K,Rb和Cs,以及它们之间的混合阳离子)。发现所有报告的化合物均显示出短的紫外线吸收边缘(<190 nm),并显示出从0.8到1.9 KH 2 PO 4(KDP)的二次谐波生成(SHG)响应。有趣的是,通过明智地选择A位碱金属阳离子,可以将NLO活性结构单元的排列微调到最佳配置,这有助于获得较大的SHG反应。
Vapour pressure and standard enthalpy of sublimation of alkali-metal fluoroborates
Abstract The temperature dependence of the vapourpressures of solid alkali-metal fluoroborates MBF4 (M = Na, Rb or Cs) were experimentally determined using an improvised transpiration technique. The vapourpressure of NaBF4 could be represented by the following least-squares expressions: log ( p / Pa ) [ NaB F 4 , orthorhombic ] = 7.06 ( ± 0.03 ) − 3734 ( ± 360 ) ( K ) / T log ( p / Pa ) [ NaB F 4
摘要 固体碱金属氟硼酸盐 MBF4(M = Na、Rb 或 Cs)的蒸气压的温度依赖性是使用简易蒸腾技术通过实验确定的。NaBF4 的蒸气压可用以下最小二乘表达式表示: log ( p / Pa ) [ NaBF 4 ,正交] = 7.06 ( ± 0.03 ) − 3734 ( ± 360 ) ( K ) / T log ( p / Pa ) [NaB F 4 ,单斜晶] = 6.03 (± 0.04 ) − 3192 (± 80 ) ( K ) / T 发现在 527 K 时与从斜方晶相到单斜晶相转变的焓为 10.4 kJ mol -1。测得的 RbBF4 和 CsBF4 的蒸气压可用以下最小二乘表达式表示: log ( p / Pa ) [ RbB F 4 ] = 6.21 ( ± 0.04 ) − 4020 ( ± 87 ) ( K ) / T log ( p / Pa ) [ CsB