Crystal structures and visible-light excited photoluminescence of N-methyl-4,4′-bipyridinium chloride and its Zn(II) and Cd(II) complexes
摘要:
A new approach has been used to synthesize MQ(+) ligand (MQ(+) = N-methyl-4,4'-bipyridinium) by the reaction of 4,4'-bipyridine and chloroacetic acid, and the structure of (MQ)Cl center dot H2O (1) was first determined. Three new complexes containing MQ(+), (MQ)CdI3 (2). (MQ)ZnI3 (3), and [(MQ)znCl(1.53)I(1.47)](2)(MQ) ZnCl1.68I1.32 (4). were successfully obtained via a solution or hydrothermal method by reaction of MI2 (M = Cd, Zn) with 1, and each of which exhibits an isolated structure, with each metal atom coordinated by one MQ ligand and three terminal halogen atoms. Compounds 1-4 all display photoluminescence in the visible region under visible-light excitation, and the origins of the emissions have been assigned to ILCT for 1 and the combination of ILCT and LLCT for 2-4. (C) 2010 Elsevier B.V. All rights reserved.
Electron‐transfer (redox) thermochromism was successfully used for switching the conductance of semiconductors, by introducing a thermally active organic component into an inorganic semiconducting framework. A moisture‐resistant semiconductor (MV)2[Pb7Br18]}n (MV2+=methyl viologen cation) has been prepared through an in situ synthetic method for MV2+. It features a rare 3D haloplumbate open framework
SHG-switching behavior and the first example of thermoswitchable NLO crystal that can maintain expected second-order NLO intensity without any heat source. The SHG-switching contrast may reach about 8 times after laser irradiation or 2 times after thermally annealing. The former value is the highest record for photoswitchable NLO crystals. This work also indicates that higher SHG-switching contrasts may
A reconstituted myoglobin with a synthetic cofactor having anionic binding sites effectively works as a photocatalyst for hydrogengeneration in the presence of monomethylated bipyridinium.
Enhanced molecular binding affinity toward aromatic dications by anthracene-derived crown ethers in water
作者:Jia-Liang Zhou、Yan-Hong Li、Ying-Ming Zhang、Ling Chen、Yu Liu
DOI:10.1039/d2ob02010f
日期:——
the ring of anthracene-derived crownether via multiple π-stacking and electrostatic interactions. Meanwhile, the obtained association constants are remarkably higher than the ones in the cases of the known benzene- and naphthalene-derived sulfonated crownethers, substantiating that the appropriate extension of π-conjugation in the molecular skeleton of crownether is a feasible method in attaining
在水中使用传统的冠醚追求高分子结合亲和力仍然是超分子化学领域的一项具有挑战性的任务,并且可能在创建先进的生物相容性纳米结构方面具有广阔的前景。在这项工作中,四磺化 1,5-dianthracenyl-42-crown-10 大大增强了与一系列结构相关的阳离子客体的分子结合强度,并通过1 H NMR、UV-vis 和荧光光谱进行了研究, 主客体结合常数在水溶液中可达 10 8 M -1个数量级。X射线晶体衍射分析进一步表明芳香族双阳离子可以紧密包裹在蒽衍生冠醚的环中通过多个 π 堆叠和静电相互作用。同时,得到的缔合常数明显高于已知苯和萘衍生的磺化冠醚的缔合常数,证明在冠醚分子骨架中适当扩展π-共轭是实现该化合物的可行方法。高度亲和的主客情结。综上所述,我们的结果表明,基于蒽的磺化冠醚可以在功能性纳米结构的制造中发展成为一类新的水溶性大环受体。
Photoinduced large magnetic change at room temperature and radical-quenched spin glass in a cyanide-bridged Mn<sup>II</sup>–Fe<sup>III</sup> compound
A cyanide-bridged MnII–FeIII compound with photoinduced large magnetic change at room temperature and radical-quenched spin glass is reported. This photomagnet presents the first example of radical-quenched spin glass in molecule based magnets.