Synthesis,crystal structure,and third-order non-linear optical properties of a new Cd(II) polymer constructed from pyrazine-2-carboxylic acid

A new cadmium(II) pyrazine-2-carboxylate coordination polymer, {[Cd(L)(H₂O)₂(SO₄)_0.5]₂·H₂O}_n (1) (HL = pyrazine-2-carboxylic acid), has been synthesized by low-temperature solid-state reaction. Single-crystal X-ray analyses reveal that 1 possesses a 3-D framework structure. The polymer 1 was characterized by elemental analyses, thermogravimetric analyses, X-ray powder diffraction analyses, IR spectra, and UV–visible spectra. The third-order non-linear optical properties were also investigated and they exhibit nice non-linear absorption and self-defocusing performance with modulus of the hyperpolarizability (γ) 1.30 × 10^?30 esu for 1 in a 2.01 × 10^?4 M?dm^?3 DMF solution.     

Synthesis,crystal structure,and third-order nonlinear optical properties of a copper(I) one-dimensional coordination polymer

A copper(I) thiocyanate coordination polymer [Cu(Phen)(μ-NCS)]n (I) (Phen = 1,10-phenan-throline) has been synthesized by the low-temperature solid-state reaction. Single-crystal X-ray analyses reveal that compound I possesses a type of one-dimensional (1D) framework structure. Polymer I was characterized by elemental analyses, IR spectra, and UV-visifele spectra. The third-order nonlinear optical properties were also investigated, and they exhibit good nonlinear absorption and self-defocusing performance with modulus of the hyperpolarizability 4.94 × 10⁻³⁰ esu for I in a 6.35 × 10⁻⁴ mol dm⁻³ DMF solution.     

Synthesis,crystal structure and magnetic properties of a two-dimensional lamellar coordination polymer manganese(II) pyrazinecarboxylate

The two-dimensional (2D) lamellar coordination polymer [Mn(pzc)₂] _n (pzc = pyrazinecarboxylate) was prepared and its structure determined by X-ray diffraction. Each Mn^II ion lies in a distorted octahedron coordination sphere, and the pzc ligand adopts two types of bridging mode. As a result, there are two different distances between adjacent Mn^II atoms: one being 3.50(6) Å via ₂-O forming a dimer of Mn^II, and the other 5.65(4) Å through the syn–anti carboxy oxygen atoms. The latter links the dimer to form an extended 2D lamellar structure. All Mn^II ions in each layer are nearly coplanar. The adjacent sheets are significantly associated via hydrogen bonding and the shortest interlayer Mn·Mn separation is 9.4 Å. The e.s.r. spectrum shows a broad isotropic band centered at g = 2.019. Temperature-dependent magnetic susceptibility measurements (2.0–300 K) reveal the presence of an antiferromagnetic interaction in the coordination polymer.     

Synthesis,crystal structure,and catalytic properties of a one-dimensional nickel(II) polymer

The title complex [Ni₂(C₁₀H₉N₃)₂(C₁₄H₈O₅)₂] _n , which has an inversion center, midway between two Ni(II) atoms forms a one-dimensional polymer bridged by 4,4′-oxydibenzoate ligands with a Ni…Ni separation of 14.4705(11) Å. The Ni(II) atom is six-coordinated by two N atoms of a bis(2-pyridyl)amine ligand and four O atoms from two 4,4′-oxydibenzoate ligands, to form a distorted octahedron coordination geometry and then are linked via N-H…O and C-H…O hydrogen bonding into a polymeric ribbon structure. The activity and selectivity profiles of the polymer indicate that the optimization temperature and time span are 175°C and 30–40 min for the dehydration of cyclohexanol, respectively.     

Synthesis,crystal structure and non-linear optical properties of a new cyanide-containing compound

Reaction of K₃[Fe(CN)₆], NiCl₂ and diethylenetriamine (dien) resulted in the formation of a cyanide-containing heterometallic compound [Ni(dien)₂]₂[Fe(CN)₆]·4H₂O 1. The structure consists of two octahedral [Ni(dien)₂]²⁺ cations, one octahedral [Fe(CN)₆]^4? anion and four crystallization water molecules, which are held together by hydrogen-bonding interactions. Its TG curve exhibits two stages of mass loss. Compound 1 in DMF solutions has a very strong third-order non-linear optical (NLO) behavior with an absorption coefficient and refractive index α₂?=?1.10?×?10^?11?m?w^?1, n ₂?=??3.05?×?10^?19?m²?w^?1, respectively, and third-order NLO susceptibility χ⁽³⁾ 4.34?×?10^?13?esu.     

Hydrothermal synthesis,crystal structure and third-order non-linear optical property of a copper chloride cluster

A novel one-dimensional chain coordination polymer [[CuCl₂]₂(phen)₂]_∞ (1) and a three-dimensional coordination polymer [[CuCl] (phen)₂](CuCl₂) (2) were synthesized from simple hydrothermal reactions and the structures were characterized with elemental analysis, FT-IR spectrum and X-ray diffraction. Compound 1 crystallized in the monoclinic space group Cc with a?=?9.874(2), b?=?17.871(4), and c?=?13.440(3)?Å, α?=?90.00°, β?=?106.59(3)°, γ?=?90.00°, R ₁?=?0.0463, wR ₂?=?0.0819. Compound 2 crystallized in the monoclinic space group P2/c with a?=?14.4084(13), b?=?12.6280(11) and c?=?13.3560(12)?Å, α?=?90.00°, β?=?111.490(2)°, γ?=?90.00°, R ₁?=?0.0771, wR ₂?=?0.1439. In the packing structure, π–π stacking interactions are the most significant factors controlling the novel supramolecular sheets for the title compound. Moreover, the third-order non-linear optical property of the two compounds were also investigated and they show reverse saturable absorption and self-focusing performance.     

Synthesis, crystal structure and non-linear optical properties of boronates derivatives of salicylideniminophenols

The condensation in one step of a series of salicylaldehydes and 2-amino-5-nitrophenol with 1-naphthylboronic acid, 2-naphthylboronic acid, and o-tolylboronic acid to give the corresponding boronates 1a-3a, 1b-3b and 1c-3d, is reported. The X-ray crystal structures of 1a, 2b and 3b allowed determining the α- and β-angle between the stilbene skeleton and the aryl or naphthylboronic fragments; these values are indicative of different conformations for the aryl moieties around the (B-C) boron-carbon bond which could potentially modulate the electronic properties on the boron stilbene compounds. All compounds were characterized by ¹H, ¹¹B and ¹³C NMR spectroscopy, UV, IR and mass spectrometry. Second- and third-order non-linear optical characterizations were also performed by EFISH and THG Maker Fringe techniques, respectively. Compounds 3a-3d containing an -N(Et)₂ donor group gave the best NLO response in second- and third-order.     

Synthesis,crystal structure,and fluorescence properties of a two-dimensional copper(II) complex with Schiff base

A new Schiff base ligand C₁₉H₁₃NO₅(H₂L) was synthesized using 2-aminoterephthalic acid and 2-hydroxy-1-naphthaldehyde. A complex of this ligand [Cu(C₁₉H₁₁NO₅)(C₂H₆O)] _n was synthesized and characterized by IR, UV, fluorescence spectroscopy and X-ray diffraction single-crystal analysis. The crystal crystallizes in the monoclinic system, space group Pbca with a = 8.7745(18), b = 18.613(4), c = 24.644(5) Å, V = 4024.9(14) ų, Z = 8, F(000) = 1816, S = 1.009, ρ _calcd = 1.462 g cm^?3, μ = 1.122 mm^?1, the final R = 0.0477 and wR = 0.1594 for 4609 observed reflections (I > 2σ(I)). The Cu(II) is five-coordinated by one N atom and two O atoms from the Schiff base ligand and two carboxylate O atoms from another two ligands to form a distorted square-pyramidal geometry. Each ligand serves as a bridging ligand to link Cu²⁺ ions, leading to a two-dimensional coordination polymer. The fluorescence properties of the ligand and complex were also studied. The ligand shows strong fluorescence, and the fluorescence intensity is weakened after the Cu(II) complex formed.     

Synthesis,crystal structure and magnetic properties of a new 1-D oxamidate-bridged Cu(II)-Mn(II) polymer

A new coordination polymer, {[Cu(aeop)Mn(H₂O)₃]₂}_n (H₄aeop = N′-(2-aminoterephthalic acid)-N′′-(1,3-propanediamine)oxamidate), has been synthesized and characterized structurally and magnetically. This complex features a 1-D ladder-like chain structure constructed from neutral tetranuclear units through the syn-anti carboxylate bridges. This crystal forms in the triclinic system, space group P 1, with a = 9.653(1) Å, b = 9.686(1) Å, c = 10.903(1) Å, α = 80.984(1)°, β = 69.776(1)°, γ = 80.729(1)° and z = 2. The relationship between its magnetic properties and structure has also been investigated.     

Heterometallic copper(Ⅱ) vanadates: synthesis,crystal structures and third-order nonlinear optical properties

Three polymeric heterometallic clusters with 1D, 2D, and 3D frameworks, constructed from a cyclic vanadate {V4O12}4-building block and three geometric constraint ligands, were synthesized by a one-pot self-assembly reaction. Z-scan experiments demonstrated that all the three cluster polymers have large hyperpolarizability γ values. TD-DFT calculations afforded insight into the electronic transitions and spectral characterization of these novel NLO molecular materials.     

The first barbiturate-bridged manganese(II) polymer: Synthesis,crystal structure,and magnetic properties

Self-assembly of barbituric acid with Mn(II) salt in slightly basic medium generates the first barbiturate-bridged polymer, [Mn(Barb)₂(H₂O)₂] _n (I) (Barb = barbiturate), which was fully characterized by single-crystal X-ray diffraction, elemental analysis, FT-IR, TG-DTA, and variable-temperature magnetic susceptibility. In the crystal, the unique octahedral Mn²⁺ ion is periodically linked into a one-dimensional linear chain by pairs of monodentate-bridging Barb anions, which is further aggregated into a three-dimensional supramolecular architecture by popular hydrogen-bonding interactions. Additionally, complex I with considerably higher thermal stability displayed weak antiferromagnetic coupling interactions between the Barb-bridged paramagnetic Mn(II) centers.     

Synthesis,crystal structure,and properties of a binuclear Zn(II) macroheterocyclic complex based on ferrocene-thiocarbazide ligand

A binuclear macroheterocyclic complex Zn₂(FcL)₂ based on ferrocene-thiocarbazide (FcL) was synthesized. X-ray diffraction analysis shows that it belongs to the monoclinic system P2(1)/n space group, with a = 1.35379(17) nm, b = 2.6026(3) nm, c = 1.8693(2) nm, β = 95.687(2)° and final R indices R = 0.0796 and Rw = 0.2119. Two Zn(II) ions and two FcL ligands form a 22-membered macroheterocycle, further extended to an infinite 1-D helical chain by intermolecular hydrogen bonding. Spectral properties of the title complex and electrochemical properties of the ligand FcL are also discussed.     

Synthesis, structure and properties of a two-dimensional iron(II) metal-organic framework

Reaction of FeSO₄·7H₂O with 5-(isonicotinamido)isophthalic acid (H₂INAIP) in the presence of NaOH results in the formation of a two-dimensional network [Fe(INAIP)(H₂O)]_n·2nH₂O. In the complex, each INAIP^2? ligand links three Fe(II) atoms to give a double-chain structure using its two carboxylate groups in ?? ₁?C?? ¹:?? ¹ and ?? ₂?C?? ¹:?? ¹ coordination modes. The chains are interlinked to form a layer structure through Fe?CN interactions, which it is extended to a three-dimensional supramolecular structure by H-bonding interactions. The thermal and magnetic properties of the complex were investigated, and antiferromagnetic interactions were observed. Moreover, the adsorption behavior shows that the title complex has obviously selective adsorption of CO₂ over N₂ after the removal of the solvent molecules within the pores.     

Synthesis,characterisation and crystal structure of a cobalt(II)-hexamethylenetetramine coordination polymer

A novel one-dimensional zigzag coordination polymer, dinitrodiaqua-bis(hexamethylenetetramine)cobalt(II) was synthesised and characterised, and the structure was determined by single-crystal X-ray diffraction. The compound has a chain structure with each cobalt atom covalently bonded to two nitrate ions, two water molecules and two HMTA molecules, giving a slightly distorted octahedral geometry about the cobalt atom. Each HMTA ligand uses two of its N atoms to bond to two cobalt atoms giving an approximately bent Co–HMTA–Co configuration. Each chain is hydrogen bonded through OH···N and OH···O interactions with neighbouring chains leading to an overall polymer structure. Thermal studies show significant mass loss corresponding to the loss of the coordinated water molecules and the decomposition of both the nitrate ions and the HMTA.     

Synthesis,crystal structure,and properties of a new zinc coordination polymer [Zn(PMP)2Cl] n

A new coordination polymer [Zn(PMP)₂Cl] _n (PMP = 1-phenyl-3-methyl-5-pyrazolone) has been prepared by the reaction of zinc chloride and PMP, and characterized by elemental analysis, IR, UV, and fluorescence spectra, TG/DTA, and electrochemical analysis. Single crystal X-ray diffraction revealed that the complex is monoclinic, space group P 2(1)/n, with a = 10.850(17), b = 17.578(2), c = 10.997(18) Å, β = 104.999(3)°, V = 2025.8(5) ų, Z = 4, D_c = 1.470 mg m^?3, F(000) = 920, goodness-of-fit = 0.905, and R ₁ = 0.0441. The complex is a 1-D coordination polymer, and the coordination geometry of Zn(II) is a distorted tetrahedron.     

1,4-双(4-吡啶基甲基苯基醚)(C18H18N2O2)与SCN^-形 成的超分子化合物[H2 (C18H18N2O2)](SCN)2的合成、结构 及其在溶液中的三阶非线性光学性质

超分子化合物[H2(C18H18N2O2)](SCN)由Fe(NO3)3·9H2O,KSCN和1,4-双(4-吡啶基甲基苯基醚)反应得到。通过X射线衍射仪测得该化合物是通过N┈H—N,S┈H—C(C5H5N)及S┈H—C(亚甲基CH2)三种氢键而形成的二维平面网状结构。用Z扫描法对该超分子在DMF溶液中的三阶非线性光学性质进行研究,发现它具有强的三阶非线性折射性能,三阶非线性超极化率X^(3)=6.27×10^-12esu.     

Synthesis,crystal structure,and luminescence properties of a one-dimensional europium(III) polymer

In the title complex, [Eu₂(C₈H₇O₃)₆(C₁₂H₈N₂)₂] _n , which has an inversion center midway between two Eu(III) atoms of the structural unit, forms a one-dimensional polymer bridged by two mondentate, two bidentate, and two tridentate carboxylate groups with an Eu-Eu separation of 4.1853(7) Å. Each Eu atom is nine-coordinated by two N atoms of a 1,10-phenanthroline (phen) ligand and seven O atoms from six phenoxyacetate ligands, to form a distorted tricapped trigonal prismatic. The luminescence spectrum of the polymer indicates that the intensity of the emission wavelength at 619 nm is the strongest among all emission wavelengths and the second phen ligand shows an enhancement effect on the luminescence of the complex.     

Synthesis,crystal structures and properties of five-coordinate Schiff-base Zn(II) complexes

Five-coordinate Schiff-base Zn complexes (1,2-cyclohexanediamino-N,N′-bis(salicylidene)) zinc-pyridine 1 and (1,2-cyclohexanediamino-N,N′-bis(3,5-di-tert-butylsalicylidene)) zinc-pyridine 2 were synthesized and the structures of 1 and 2 have been determined by single-crystal X-ray analysis. All Zn atoms are five-coordinate in both structures. Both complexes exhibit interesting structures based on intermolecular π–π stacking and hydrogen bond interactions. Complex 1 has a one-dimensional molecular chain structure via π–π stacking interaction, while complex 2 has an interesting lattice structure (with cavities with dimensions 10.9?×?6.9?Å) formed through intermolecular π–π stacking and hydrogen bond interactions. 1 and 2 are compared and characterized by MS, elemental analysis, IR, UV-Vis and Photoluminescence (PL). Fluorescence spectra show that the maximal emission wavelength of 1 and 2 are 454?nm, and 480?nm, respectively, upon radiation by UV light. Cyclic voltammetry performed on 1 and 2 indicate a dependence of the cathodic potentials upon conformational and electronic effects. Electronic spectral properties of 1 and 2 were studied by TD-DFT methods. The fluorescent emission of these complexes originates from ligand-centred π–π? transitions. The Zn (II) centres play a key role in enhancing the fluorescent emission of the ligands.     

Synthesis, structure and non-linear optical property of a copper(II) thiocyanate three-dimensional supramolecular compound

A novel copper(II) thiocyanate complex [Cu(im)₂(NCS)₂] 1 (im=imidazole) has been prepared and characterized by spectroscopic analysis and crystallographic method. This supramolecular compound exhibits a three-dimensional solid state structure constituted by N–HS hydrogen bonds and π–π stacking interactions. The compound in DMF solutions has a very strong third-order non-linear optical (NLO) behavior with absorption coefficient and refractive index ₂=1.18×10⁻¹¹ mw⁻¹, n₂=−9.00×10⁻¹⁶ m²w⁻¹, respectively, and third-order NLO susceptibility χ⁽³⁾ of 7.00×10⁻¹⁰ esu.     

L-alaninium perrhenate: crystal structure and non-linear optical properties

The crystal structure and non-linear optical properties of L-alaninium perrhenate, C₃H₈NO²⁺ ReO₄ ^?, are reported. The protonated amino acid and the perrhenate anion have their usual geometries. The three-dimensional hydrogen-bonded network can be seen as a stacking of layers parallel to the (100) planes. Each layer is formed by chains of alternating positive and negative ions along the b and c axes. Hydrogen bonding of adjacent layers forms alternating chains along the a axis. A high damage threshold and a second-harmonic generation efficiency three times that of KDP make this new material potentially useful in non-linear optics.