Preparation of Cadmium(II) Oxide Nanoparticles from a New One-Dimensional Cadmium(II) Coordination Polymer Precursor; Spectroscopic and Thermal Analysis Studies

A one-dimensional Cd(II) coordination polymer containing 2-pyridinecarboxylate (2-pyc⁻) and iodide anions [Cd(μ-2-pyc)(μ-I)] _n (1), is synthesized and characterized by elemental analysis, IR spectroscopy, thermal analysis and X-ray crystallography. The single-crystal X-ray data show that the coordination number for the Cd²⁺ ion is five. The thermal stability of 1 was studied by thermogravimetry and differential thermal analyzes. Cd(II)O nanoparticles were prepared by direct calcination of 1 at different temperatures. The Cd(II)O nanoparticles were characterized by X-ray powder diffraction and scanning electron microscopy. The results show that the morphology of the Cd(II)O nanoparticles is dependent upon the thermolysis temperature.     

One-Dimensional Coordination Polymer of Zinc(II)-pyridine-2,5-dicarboxylate with N,N-Dimethylethylenediamine: Synthesis, Structural, Spectroscopic and Thermal Properties

In this study, a new polymeric Zn(II)-pyridine-2,5-dicarboxylate complex with N,N-dimethylethylenediamine (dmen), {[Zn(pydc)(dmen)(H₂O)]·H₂O} _n (1) (pydc = pyridine-2,5-dicarboxylic acid or isocinchomeronic acid), has been synthesized. Elemental, thermal analysis and IR spectroscopic study have been performed to characterize the complex. The molecular structure of complex has been determined by the single crystal X-ray diffraction. 1 has been observed to crystallize in the orthorhombic space group Pbca. The Zn(II) atom is coordinated by the tridentate pydc bridging ligand through the oxygen atom of the carboxylate group and the nitrogen atom of the pyridine ring in a bidentate manner and the oxygen atom of carboxylate group of other pydc ligand. Each Zn(II) ion is also coordinated by a bidentate dmen and one aqua ligand forming a distorted octahedral geometry. The crystal packing of complex is a composite of intermolecular hydrogen bonding with C=O?π and C–H?π interactions.     

Sonochemical Synthesis of One-Dimensional Nano-structure of Three-Dimensional Cadmium(II) Coordination Polymer

Nano-wires and nano-rods of a new three-dimensional cadmium(II) coordination polymer, {[Cd₃(3-pyc)₄(NCS)₂(H₂O)₄]·2H₂O} _n (1); 3-Hpyc = 3-pyridinecarboxilic acid, were synthesized by a sonochemical method in two different concetrations. The morphology of the nano-structures depend strongly on reactants’ concentration. The new nano-structures were characterized by scanning electron microscopy, X-ray powder diffraction, elemental analyses and IR spectroscopy. Compound 1 was structurally characterized by single-crystal X-ray diffraction and is a three-dimensional polymer with two types of Cd(II) coordination environments.     

Sonochemical Synthesis of Nano-structured Lead(II) Coordination Polymer with 2-Aminonicotinic Acid: Thermal, Structural and X-ray Powder Diffraction Studies

A new one-dimensional crystalline and nano-structured Pb(II) coordination polymer, [Pb(2-anc)₂(NO₃)₂] _n (1) {2-Hanc?=?2-aminonicotinic acid}, were synthesized via heat gradient and sonochemical methods. The new produced nano-structure was characterized by scanning electron microscopy, X-ray powder diffraction, IR spectroscopy, and elemental analyses. Structural characterization by single crystal X-ray diffraction exhibits two-dimensional polymeric units for compound 1. Thermal stability of nano and bulk samples of compound 1 were studied and compared. PbO nano-particles was then obtained via calcination of nano-compound 1 at high and low temperatures. The calcinations result demonstrates that compound 1 may be suitable precursor for the preparation of nanoscale lead(II) oxide without need for special conditions like high temperature, long times and pressure control.     

One-Dimensional Cobalt(II) and Zinc(II) Succinato Coordination Polymers with Nicotinamide: Synthesis, Structural, Spectroscopic, Fluorescent and Thermal Properties

Cobalt(II) and zinc(II) succinato (suc) coordination polymers with nicotinamide (nia), {[Co(μ-suc)(H₂O)₂(nia)₂] · 2H₂O} _n (1) and {[Zn(μ-suc)(H₂O)₂(nia)₂] · 2H₂O} _n (2) have been synthesized and characterized by elemental analyses, magnetic moments, IR and TG-DTA. Single-crystal X-ray analyses of 1 and 2 reveal that these complexes are isostructural and crystallize in triclinic space group Complexes 1 and 2 are 1-D coordination polymers, in which the metal(II) ions exhibit an octahedral geometry with two suc, two nia and two aqua ligands. The nia ligand is N-bonded, while the suc ligand bridges the metal centers through the carboxylate groups. The 1D chains are further assembled to form 3D networks by strong N–H···O and OW–H···O hydrogen bonds. IR spectra confirm the coordination modes of both suc and nia ligands, while TG-DTA data are in agreement with the crystal structures. Fluorescent analysis in the solid state shows that all complexes display intraligand (π–π*) emissions of nia.     

Hydrothermal Preparation, Crystal Structures, Spectroscopic and Thermal Analyses of Cadmium(II) and Cobalt(II) Coordination Polymers With Pyridine-2,3-dicarboxylic Acid

Two novel 1D coordination polymers, [M(μ-2,3-pydc)(H₂O)₃]_n (M = Cd for 1 and Co for 2) (2,3-pydcH₂ = pyridine-2,3-dicarboxylic acid) have been hydrothermally synthesized. Both complexes were characterized by elemental analysis and by IR and UV–Vis spectroscopy. Their molecular and crystal structures were determined by X-ray crystal structure analysis and their thermal stability by TGA-DTA methods. Compound 1 crystallizes in the orthorhombic Pca2 space group, while compound 2 crystallizes in the triclinic P−1 space group. Polymeric chains of 1 and 2 are composed of M(II) ions bridged by pyridine-2,3-dicarboxylate ions (2,3-pydc) in N,O,O′ fashion. Distorted octahedral coordination geometry around the metal ions is completed by three water molecules. A wide range of hydrogen bonding (of the O–H···O type) is also present in the crystal structures. These interactions lead to formation of a 3D structure for 1 and 2D network for 2.     

Synthesis, Crystal Structure, Spectroscopic and Thermal Investigations of a Novel 2D Sodium(I) Coordination Polymer Based on 2-Aminoterephthalic Ligand

The reaction of sodium hydroxide with 2-aminoterephthalic acid leads to the formation of a complex of the general formula: [Na₂(atpt)(H₂O)₅]·H₂O, where atpt?=?[NH₂C₆H₃(COO)₂]^2?. Sodium 2-aminoterephthalate was synthesized and characterized by single-crystal X-ray diffraction, FT-IR spectroscopy, thermal analysis and coupled TG–FT-IR technique. Crystallographic study of the sodium complex reveals that the compound crystallizes in the triclinic system, the space group P-1 with a?=?7.983(3) ?, b?=?8.405(3) ?, c?=?11.311(5) ?, α?=?70.74(3)°, β?=?76.57(3)°, γ?=?83.12(3)° and V?=?696.1(5) ?³. On heating in air atmosphere the compound in question loses all water molecules in two steps in the temperature range 30–205?°C. The anhydrous form of the complex is stable up to 370?°C and then decomposes to sodium carbonate.     

Synthesis,Crystal Structure and Luminescence Property of a New (6,3)-Connected Zn(II) Coordination Polymer

The 2D coordination polymer, [Zn(dpa)(bpp)] _n (H₂dpa = 2,4′-biphenyl-dicarboxylic acid, bpp = 1,3-di(4-pyridyl)propane) was prepared by hydrothermal synthesis in the presence of NaOH and characterized by single-crystal X-ray diffraction, FTIR spectra, element analysis and thermal analysis. The crystal structure determination reveals that the carboxylate groups of 2,4′-biphenyldicarboxylic acid are acting as bridging ligands and adopt two coordination modes; bis-monodentate and bidentate chelating. The network consists of a 2D (6,3)-connected architecture. At room temperature the solid-state luminescence spectrum of [Zn(dpa)(bpp)] _n shows a blue emission at about 354 nm upon excitation at 333 nm.     

一维NiⅡ配合物的合成、结构及热稳定性

在甲醇-水溶剂中,用四溴代对苯二甲酸(H2TBTA)、1,3-二(4-吡啶基)丙烷(BPP)、硝酸镍为原料合成了一维链状配合物[Ni(BPP)2(TBTA)(H2O)2]n。该配合物晶体中NiII金属离子与两个BPP的两个N原子、两个H2TBTA中的两个羧基O原子及两个水分子中的O原子配位,形成六配位的变形八面体结构。晶胞参数:三斜晶系,P-1空间群,a=9.444(5),b=9.602(5),c=11.356(6),V=882.2(8)3,Z=1,Dcalc=1.828 mg/mm3,R1[I>2σ(I)]=0.0329,wR2(all data)=0.1058。对晶体进行热稳定性分析表明:配合物在122℃以下稳定性良好。     

Synthesis, Crystal Structure and Antitumor Activity of Ca(II) Coordination Polymer Based on 1,5-Naphthalenedisulfonate

A novel Ca(II) coordination polymer, [CaL(H₂O)₂] _n (L = 1,5-naphthalenedisulfonate), was synthesized by reaction of calcium perchlorate with 1,5-naphthalenedisulfonic acid sodium in CH₃CH₂OH/H₂O. It was characterized by elemental analysis, IR, ¹HNMR and thermal analysis. X-ray crystallographic reveals that the Ca(II) coordination polymer belongs to triclinic system, with space group P-1. The geometry of the Ca(II) ion is a distorted CaO₆ octahedron coordination environment, arising from its coordination by two water molecules, and four oxygen atoms from two l ligands. The Ca(II) ions are linked through the O atoms of 1,5-naphthalenedisulfonate ligands to form 1D chain structure. And then a 2D layered structure is constructed by hydrogen bonds and π–π stacking. The antitumor activity of 1,5-naphthalenedisulfonic acid sodium ligand and its Ca(II) coordination polymer against human hepatoma smmc-7721 cell line and human lung adenocarcinoma A549 cell line have been investigated.     

Synthesis, Crystal Structure and Magnetic Properties of a Nickel(II) Coordination Polymer Based the V-Shaped Ligands

Abstract  

A new nickel(II) coordination polymer, Ni₂(DBA)₂(BIDPE)₂(H₂O) (1) (H₂DBA = 4,4′-methylenedibenzoic acid and BIDPE = 4,4′-bis(imidazole-l-yl)diphenyl ether), has been prepared by hydrothermal synthesis and structurally characterized by IR, elemental analysis, TGA and single crystal X-ray diffraction. Complex 1 features a one-dimensional chain structure based on triply bridged binuclear units, which is further interlinked into a higher-dimensional supramolecular framework by intermolecular weak interactions. Variable-temperature magnetic data shows weak antiferromagnetic behavior in 1.     

Synthesis and Characterization of Zinc(II) Oxide Nanoparticles by Thermal Decomposition of Two Zinc(II) Nitrite Coordination Polymer Precursors

Two zinc(II) coordination polymers, {[Zn(3-bpdb)(NO₂)]·0.5H₂O} _n (1) and [Zn(4-bpdb)(NO₂)₂] _n (2), 3-bpdb = 1,4-bis(3-pyridyl)-2,3-diaza-1,3-butadiene and 4-bpdb = 1,4-bis(4-pyridyl)-2,3-diaza-1,3-butadiene}, have been synthesized and characterized by elemental analyses and IR spectroscopy. Nanoparticles of zinc(II) oxide have been prepared by thermolyses of two different zinc(II) coordination polymers, 1–2. The nano-materials were characterized by scanning electron microscopy, X-ray powder diffraction and IR spectroscopy. The thermal stability of ZnO nano-particles was studied by thermal gravimetric and differential thermal analysis and showed that there is no loss of weight, which indicates that the products were zinc(II) oxide. This study demonstrates the coordination polymers may be suitable precursors for the preparation of nanoscale materials.     

Preparation of Zinc(II) Oxide Nanoparticles from a New Nano-Size Coordination Polymer Constructed from a Polypyridyl Amidic Ligand; Spectroscopic, Photoluminescence and Thermal Analysis Studies

A new zinc(II) coordination polymer, {[Zn(bpcdp)₂(DMF)₄](ClO₄)₂·(H₂O)₂}_n (1) bpcdp = 2,6-bis(4-pyridinecarboxamide)pyridine has been synthesized and characterized by IR, ¹HNMR and ¹³CNMR spectroscopy. The single crystal X-ray data of compound 1 shows the zinc(II) atom has been considered as octahedral with ZnN₂O₄ coordination sphere. Two nitrogen atoms of bpcdp ligand and four oxygen atoms of DMF molecules have occupied coordination sphere around zinc(II) atoms. The prepared zinc(II) coordination polymer grows in three-dimensional network by hydrogen bonding and π–π stacking interaction. The nanostructure of compound 1 were obtained by sonochemical process and studied by scanning electron microscopy (SEM), X-ray powder diffraction (XRD), IR and NMR spectroscopy. Thermal stabilities of single crystalline and nano-size samples of compound 1 were studied by thermal gravimetric (TG) and differential thermal analyses (DTA). The ZnO nanoparticles were obtained by direct calcination of compound 1 at 400 °C and by thermolysis in oleic acid at 200 °C. The obtained zinc(II) oxide nanoparticles were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM).     

Synthesis,Crystal Structure and Luminescent Property of a New Zn(II) Coordination Polymer with Twofold Interpenetrated pcu Topology

A new Zn(II) coordination polymer; namely, [Zn(FA)(bmix)_0.5] _n ·nH₂O (1, H₂FA = fumaric acid, bmix = 1,4-bis(2-methyl-1H-imidazol-1-ylmethyl)benzene) was synthesized with fumaric acid and flexible 2-methylimidazole-based ligands with Zn(II) salts under hydrothermal conditions. Single-crystal X-ray diffraction reveals that 1 features a twofold interpenetrating three-dimensional pillar-layered framework based on paddle-wheel shaped [Zn₂(COO)₄] subunits. The structure may be simplified to a 6-connected pcu topological network. Luminescent investigation reveals that 1 exhibits intense ligand-centered fluorescence at room temperature.     

Synthesis,Crystal Structure,Spectroscopic and Thermal Analysis of Strontium Pyrophosphate Dihydrate Nanoparticles

Various pyrophosphates are very useful as bioceramics; for instance, strontium pyrophosphate is one of the emerging forms of alkaline phosphate. Strontium pyrophosphate dihydrate (Sr₂P₂O₇2H₂O) nanoparticles were synthesized by the surfactant‐mediated approach and characterized by different techniques. From the powder XRD study, the average crystallite size was evaluated by applying Scherrer's formula, which was found to be 33.57 nm. The average crystallite size and internal strain were also evaluated using Williamson–Hall (W‐H) method. The FT‐IR spectroscopy study confirmed the presence of symmetric and asymmetric stretching vibrations of P–O–P and PO₃. The UV‐NIR absorption spectroscopy over the spectral range of 210–1200 nm was employed, and the energy band gap was calculated from Tauc's plot which was found to be 4.9 eV. Thermogravimetric analysis (TGA) confirmed the presence of two water molecules in the sample. From TGA, it was found that the sample become anhydrous and on heating above 410–800°C, the sample remained almost stable with slight weight gain due to adsorption of purged gas. Various kinetic parameters and thermodynamic parameters were evaluated for dehydration process.