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We have introduced an extremely low-molecular-weight organic gelator with a Cd(II) source to obtain a supramolecular Cd(II) metallohydrogel. Microstructural analysis of the gel has been performed. ...

The combination of two 8-aminoquinoline-based Schiff base ligands (L1 and L2) with SCN– and Ni(II) has led to the synthesis of two new one-dimensional thiocyanato-bridged coordination polymers: [Ni...

A heteroporous metal–organic framework, [Cd2(2,2′-DSB)2(INH)2(H2O)2]n (1), is fabricated by the reaction of CdI2, 2-mercaptobenzoic acid (2-MBAH), and isoniazid (INH). The X-ray structure of the co...

An intriguing functional supramolecular Tb(III)-metallogel (Tb-OX) has been derived through the sonication of Terbium(III) chloride hexahydrate and oxalic acid dihydrate in N,N-dimethyl formamide (...

A newly designed multifunctional two-dimensional coordination polymer (2D CP) {[Cd(suc)(4-nvp)2]·2H2O}n, (1), (H2suc = succinic acid and 4-nvp = 4-(1-naphthylvinyl)pyridine) has been synthesized an...

Two Cu(II)-malonate complexes with 2-amino-4-methylpyridine (complex 1) and 2-aminopyrimidine (complex 2) auxiliary ligands were synthesized, and their single-crystal X-ray diffraction structures were established. Change in the auxiliary ligand exhibits substantial structural variation in the present complexes. Complex 1 shows a one-dimensional anionic copper-malonate moiety connected by the malonate bridge, whereas complex 2 is a mononuclear one. For both the complexes, auxiliary ligands are attached with the Cu-malonate moiety through various noncovalent interactions. Optical band gap, electrical conductivity, and photosensitivity of complexes 1 and 2 were measured, but the values of electrical parameters of the complexes significantly differ from each other. However, the magnitudes of electrical parameters increase several times for both the complexes when they are exposed under visible light, though the values of light sensing parameters of complex 1 were found to be higher than those of complex 2. Density functional theory calculations for complex 1 were carried out to support the experimental result.

Three Cd(II) based coordination polymers (CPs) (1–3) are designed using 3-aminoquinoline and 5-aminoquinoline based Schiff base ligands and thiocyanate and dicyanamide as bridging ligands. Pseudoha...

A functional supramolecular Mn(II)-metallogel (Mn@OX) has been synthesized through the direct mixing of manganese(II) acetate tetrahydrate and oxalic acid dihydrate, a low molecular weight gelator ...

A metal-organic compound [Cd(quin)2(4-nvp)2] [1; Hquin = quinoline-2-carboxylic acid and 4-nvp = 4-(1-naphthylvinyl)pyridine] undergoes topochemical [2 + 2] cycloaddition by sunlight irradiation to generate a one-dimensional coordination polymer. This reaction is thermally reversible, and switching between two crystalline forms can be monitored by conductivity measurements.

The porous materials are efficient storage and exchange systems of small molecules and ions. Some of the porous materials may be used as an efficient storage system of iodine. Herein, a honeycomb (...

Two zinc(II) based metal complexes, [Zn(Pymox)Cl2] (1) and [Zn6(Pymox)6(μ2-O)3] (2), where Pymox = 3-[(4,6-dimethyl-pyrimidine-2-yl)-hydrazono]-butan-2-one oxime, have been synthesized and characterized by elemental analysis, IR, and single crystal X-ray diffraction studies. Single crystal X-ray analysis confirms that one of the synthesized products (1) is a mononuclear complex and another (2) is a hexanuclear Zn complex. The optical band gap energy in both the complexes (3.43 eV in 1 and 2.36 eV in 2) from solid state UV measurement explores semiconductor behavior of the synthesized materials. The dielectric parameters such as charge transfer resistance, room temperature dc conductivity and electron lifetime measurement shows the superiority of complex 2 over complex 1. Therefore, the Schottky barrier diode (SBD) electronic devices were fabricated by using these two complexes with aluminum (Al) and indium tin oxide (ITO) in sandwich configuration—ITO/1 or 2/Al. Both the devices exhibit sound rectificatio...

Syntheses, structural characterizations, photoluminescence, and adsorption properties of three new azo-functionalized Cd(II)-MOFs, namely, {[Cd(azbpy)(msuc)]·2.5(H2O)}n (2), {[Cd(azbpy)(mglu)]·5(H2O)}n (3), and {[Cd1.5(azbpy)2(glu)]·(NO3)·MeOH}n (4) [where msuc2- = methylsuccinate; mglut2- = methylglutarate; glut2- = glutarate; azbpy = 4,4'-azobispyridine] have been reported. The compounds show different structures only with the variation of aliphatic dicarboxylates. The photoswitching behavior for the above-mentioned newly synthesized Cd(II)-MOFs along with one of our previously reported other azo-functionalized Cd(II)-MOF, namely, {[Cd(azbpy)(suc)]·2(H2O)}n (1), has been studied extensively. At photoilluminated condition, the conductivity values can draw a clear structure-property relationship among the structures of compounds 1-4. Single crystal structural analysis reveals that all the compounds exhibit a three-dimensional (3D) framework connected by azbpy linker and respective aliphatic dicarboxylate through their bis-chelating mono/bis oxo-bridging fashion. Compounds 1-3 exhibit an iso-structural honeycomb like 3D framework showing the same coordination environments, where the metal-carboxylate 2D sheets of compounds 1-3 are pillared by N,N'-donor azbpy linkers. On the other hand, compound 4 exhibits a 2-fold interpenetrated 3D framework with a little difference in its coordination environment and the pillaring of 1D metal-carboxylate ladder by azbpy linkers. All the compounds significantly demonstrate their enhanced sensitivity under light rather than the dark condition. The gas and solvent vapor sorption studies have been performed for the synthesized compounds 2-4. Moreover, compound 2 exhibits an enhanced type IV selective CO2 adsorption isotherm over N2 along with the appearance of gate opening phenomena in that.

Three new coordination polymers (CPs) of coordinated isoniazid (INH) to Zn(II) with succinic acid (H2succ), fumaric acid (H2fum), and terephthalic acid (H2bdc) as organic linker, [Zn(INH)(succ)]n (1), [Zn(INH)(fum)]n (2), and [Zn(INH)(bdc)]n (3), respectively, have been characterized. The structure determination by the single crystal X-ray diffraction technique shows a ZnN2O4 distorted octahedral geometry, and the 1D chain is constituted via the INH and carboxylate coordination along with the hydrogen bonding (N–H···O) which comprises a 2D structure. The CPs, 1 and 2, are isostructural and fabricate supramolecular networks by inclined intercatenation of two 2D layers, while 3 shows parallel intercatenation. The electrical conductivity and Schottky barrier diode behavior have been established by the charge transport mechanism of the compounds at the quasi-Fermi level state. The analysis indicates that the compound 1 has the highest mobility (2.53 × 10 –10 m2 V–1 s–1) than 2 (1.86 × 10–10 m2 V–1 s–1) and 3 ...

We have investigated the origin of ionic conductivity in methylammonium lead iodide (MAPbI3) by positron annihilation lifetime spectroscopy (PALS), supplemented by coincidence Doppler broadening spectroscopic (CDBS) techniques which reveal the presence of methylammonium (MA+) defects in the perovskite crystal lattice. Crystallinity and the defect concentration vary with the perovskite synthesis process, which in turn governs the magnitude of ionic conductivity. Single-crystalline perovskite contains lesser defects with equal probability of developing both cationic and anionic (halide) vacancies, whereas the polycrystalline perovskite sample developed through mechanical process carries mainly cationic, i.e., MA+ vacancy (V′MA) in its crystal lattice as indicated by direct current (dc) polarization experiment.

The simple and small organic compound bis((quinolin-4-yl)methylene)benzene-1,4-diamine (BQD) has been synthesized by a one-step Schiff-base condensation reaction, and it has been characterized by elemental analysis, some standard spectroscopic methods, and the X-ray single crystal diffraction technique. It shows the unique property of photosensitivity with about 10 times increase in electrical conduction under irradiation of visible light of a specific wavelength (700 nm), in comparison to dark conditions. However, UV light (350 nm) or visible light of different wavelength (500 or 600 nm) cannot cause an enhancement in its electrical conduction. The electric current measurement of BQD exhibits its response ability toward visible light but not to UV illumination when current is measured several times under a constant bias voltage by putting light on and off with successive repetitions. Theoretical calculations indicate that a slight conformational change in the C═N bond and dihedral angle leading to the in...