Three Ln^III coordination compounds based on 1,1′,1″-(benzene-1,3,5-triyltris(methylene))tris(4-carboxypyridinium)tribromide: Synthesis, structures, and properties

<p>An exploration of reactions of 1,1′,1″-(benzene-1,3,5-triyltris(methylene))tris(4-carboxypyridinium)-tribromide (H₃LBr₃) with Ln^III salts has led to the formation of three complexes, {[LnL(H₂O)₂]·3(NO₃)·6H₂O} (Ln = Eu (<b>1</b>), Gd (<b>2</b>), and Tb (<b>3</b>)). Single-crystal X-ray analyses revealed that these complexes are isomorphous and have 3-D, channel-like structures, in which the carboxylic acids are fully deprotonated with <i>syn</i>–<i>syn</i> μ₂-<i>η</i>¹:<i>η</i>¹ type bridging modes and L ligands in a chair-shaped configuration. Both <b>1</b> and <b>3</b> showed strong luminescence upon excitation. Magnetic measurements were performed for <b>2</b> and <b>3</b>. The magnetic studies show that very weak antiferromagnetic couplings exist between Gd^III and Gd^III in <b>2</b>. Moreover, powder X-ray diffraction, infrared spectroscopy, and elemental analysis were also performed.</p

SCSC Transformation and Post-Synthesis Modification of MOFs with Proton Conduction and Ratiometric Fluorescence-Sensing Properties

The modification of metal–organic framework (MOF) materials to facilitate their practical applications is an extremely challenging and meaningful topic. In this work, two stepwise modification strategies for MOFs were conducted. First, we have demonstrated a single-crystal-to-single-crystal (SCSC) transformation from a microporous three-dimensional (3D) MOF to a two-dimensional (2D) coordination polymer (CP). The centrosymmetric [Cd­(3-bpdb)­(MeO-ip)]n (1) transforms into a chiral [Cd2(3-bpdb)­(MeO-ip)2(CH3OH)2]n (2), which is triggered by the reaction time with methanol that acts as a structure-directing agent. The conversion relationship of 1 to 2 at different reaction times was studied in detail. Density functional theory (DFT) calculations clearly state that the irreversible formation of 2 is thermodynamically favorable. Intriguingly, 2 exhibits good proton conduction of 1.34 × 10–3 S cm–1 under 363 K and 98% relative humidity (RH) due to unique H-bond network characteristics. To the best of our knowledge, there are very few cases of 3D to 2D SCSC transformation stimulated by reaction time. The results have important implications for understanding the SCSC transformation mechanism and synthetic chemistry. On the other hand, the lanthanide3+-functionalized hybrids (Ln3+-MOF), Ln3+@1, were continuously prepared by incorporating luminescent Ln3+ ions into the structure of 1 through encapsulating post-synthesis modification (PSM). Tb3+@1 exhibits double emission in water and shows visual ratiometric fluorescence behavior for sensing glutamic acid (Glu), tryptophan (Trp), and Al3+, which is more reliable and accurate than single emission. Our work may not only provide new insights into the multiple modification of MOF materials but also promote the practical application of such materials

SCSC Transformation and Post-Synthesis Modification of MOFs with Proton Conduction and Ratiometric Fluorescence-Sensing Properties

The modification of metal–organic framework (MOF) materials to facilitate their practical applications is an extremely challenging and meaningful topic. In this work, two stepwise modification strategies for MOFs were conducted. First, we have demonstrated a single-crystal-to-single-crystal (SCSC) transformation from a microporous three-dimensional (3D) MOF to a two-dimensional (2D) coordination polymer (CP). The centrosymmetric [Cd­(3-bpdb)­(MeO-ip)]n (1) transforms into a chiral [Cd2(3-bpdb)­(MeO-ip)2(CH3OH)2]n (2), which is triggered by the reaction time with methanol that acts as a structure-directing agent. The conversion relationship of 1 to 2 at different reaction times was studied in detail. Density functional theory (DFT) calculations clearly state that the irreversible formation of 2 is thermodynamically favorable. Intriguingly, 2 exhibits good proton conduction of 1.34 × 10–3 S cm–1 under 363 K and 98% relative humidity (RH) due to unique H-bond network characteristics. To the best of our knowledge, there are very few cases of 3D to 2D SCSC transformation stimulated by reaction time. The results have important implications for understanding the SCSC transformation mechanism and synthetic chemistry. On the other hand, the lanthanide3+-functionalized hybrids (Ln3+-MOF), Ln3+@1, were continuously prepared by incorporating luminescent Ln3+ ions into the structure of 1 through encapsulating post-synthesis modification (PSM). Tb3+@1 exhibits double emission in water and shows visual ratiometric fluorescence behavior for sensing glutamic acid (Glu), tryptophan (Trp), and Al3+, which is more reliable and accurate than single emission. Our work may not only provide new insights into the multiple modification of MOF materials but also promote the practical application of such materials

Supplementary_material – Supplemental material for Monoaminergic Genetic Variants, Prefrontal Cortex–Amygdala Circuit, and Emotional Symptoms in Children With ADHD: Exploration Based on the Gene–Brain–Behavior Relationship

Supplemental material, Supplementary_material for Monoaminergic Genetic Variants, Prefrontal Cortex–Amygdala Circuit, and Emotional Symptoms in Children With ADHD: Exploration Based on the Gene–Brain–Behavior Relationship by Lu Liu, Qihua Zhao, Xiaoyan Yu, Defeng Xu, Haimei Li, Ning Ji, Zhaomin Wu, Jia Cheng, Yi Su, Qingjiu Cao, Li Sun, Qiujin Qian and Yufeng Wang in Journal of Attention Disorders</p