Magnetic and Photochromic Properties of a Manganese(II) Metal-Zwitterionic Coordination Polymer

Abstract

The solvothermal reaction of Mn(ClO4)2, NaN3, and a rigid viologen-tethered tetracarboxylic acid (1,1'-bis(3,5-dicarboxyphenyl)-4,4'-bipyridinium chloride, [H4L]Cl2) led to a coordination polymer of formula [Mn4(L)(N3)6(H2O)2]n. X-ray analysis revealed a 3D coordination structure. The Mn(II) ions are connected by mixed azide and carboxylate bridges to give 2D layers, which are pillared by the viologen tether of the zwitterionic ligand. Magnetic analyses suggested that the compound features antiferromagnetism and field-induced metamagnetism. The compound also shows photochromic and photomagnetic properties. The long-range magnetic ordering is owed to the spin-canting structure of the Mn(II)-azide-carboxylate layer; the photochromism involves the formation of viologen radicals via photoinduced electron transfer, and the photomagnetism is related to the interactions between the metal ion and the photogenerated radicals. The study demonstrates a strategy for the design of new multifunctional materials with photoresponsive properties.

A Zwitterionic Ligand‐Based Cationic Metal‐Organic Framework for Rapidly Selective Dye Capture and Highly Efficient Cr2O72− Removal

“…All chemicals were of reagent grade quality and obtained from commercial sources without further purification except for the [H 4 L]Cl 2 ([H 4 L] 2+ =1,1′‐bis(3,5‐dicarboxyphenyl)‐4,4′‐bipyridinium) ligand that was prepared according to previous work . All UV/Vis absorption spectra were performed at room temperature on a Shimadzu UV‐2450 spectrophotometer.…”

“…2018, 24,2 718 -2724 www.chemeurj.org ligand that was prepared according to previous work. [21] All UV/Vis absorption spectra were performed at room temperature on aS himadzu UV-2450 spectrophotometer.T he CHN elemental analyses were collected by aP erkinElmer 2400 elemental analyzer.T hermogravimetric analyses (TGA) were measured on aP erkinElmer TGA-7 thermogravimetric analyzer from room temperature to 800 8Ci naira tmosphere, with ah eating rate of 10 8Cmin À1 .T he IR absorption spectra were obtained in the range of 400-4000 cm À1 on aN icolet Impact 410 FTIR spectrometer as KBr pellets. Powder X-ray diffraction (PXRD) patterns were collected on aR igaku D-Max 2550 diffractometeru sing Cu Ka radiation (l = 0.15418 nm) in a2 q range of 4-408 at room temperature.…”

Synthesis and characterization of a photochromic magnesium(II) coordination polymer based on a naphthalene diimide ligand

“…The potential applications of coordination polymers are widespread and span many fields, such as energy storage (Suh et al, 2012), chemical purification (Li et al, 2012), sensing (Yanai et al, 2011;Kreno et al, 2012;, heterogeneous catalysis (Chistyakov et al, 2013;Mancina & Tecilla, 2007;Liu et al, 2014) and as components in optical devices (Lu et al, 2006;Hu et al, 2014). Much work is currently focused on functionalizing metal-organic frameworks (MOFs) through chemical modifications to and the chemical anchoring of organic linkers, because these are effective strategies for the design of MOF materials with desirable photophysical properties (Yang et al, 2011;Yanai et al, 2012;Toma et al, 2016;Gong et al, 2016;Lv et al, 2017). Photochromic materials have received much attention not only due to their colour change upon irradiation but also to their potential applications as sensors, photoswitches, erasable prints, and so on (Wang et al, 2010;Pardo et al, 2011;Li et al, 2014;Cai et al, 2015).…”

N-donor co-ligands driven two new Co(II)- coordination polymers with bi- and trinuclear units: Crystal structures, and magnetic properties

“…However, the final structures of coordination polymers are hardly controlled because the synthesis processes are influenced by many factors, such as the structural characteristics of the ligands, the coordination nature of metal ions, the solvent preference, the pH value of the solution, the reaction temperature and the metal/ligand ratios. Multicarboxylate ligands, which are widely employed to construct such extended architectures, not only bind several metal centers of specific coordination geometry to form polynuclear units but also can transmit the magnetic interaction [34][35][36]. Biphenyl-2,4,6,3',5'-pentacarboxylic acid (H 5 bppc) is an important family of mutidentate O-donor, which can be used as the mediators between the metal centers, because multicarboxylate groups have various coordination modes, which allowing interesting structures with higher dimensionality.…”