Synthesis,Crystal Structure,and Physical Properties of a ­Barium(II) Benzene‐1, 2, 3‐tricarboxylic Acid Complex

A coordination polymer [Ba₁₂(btc)₈(H₂O)₂₃] ( 1 ) was obtained by self‐assembly of the corresponding metal carbonate with benzene‐1, 2, 3‐tricarboxylic acid ligand (H₃btc), and its structure was determined by single‐crystal X‐ray diffraction studies. The results revealed that complex 1 has a three dimensional structure. In 1 , the btc^3– anions adopt four different conformation and coordination modes. Bridging btc^3– anions and μ₂‐bridging water molecules connect Ba^II ions to generate a two dimensional layer. Further, μ₂‐bridging coordinated water molecules connect the Ba^II ions of neighboring layers to form a three dimensional structure. Additionally, the luminescent property and thermal stability of 1 were investigated.     

Synthesis,Structure, and Physical Properties of a Barium Complex with 5‐Sulfoisophthalic Acid Sodium Salt

The complex [Ba₃(sip)₂(H₂O)₉] · H₂O ( 1 ) (NaH₂sip = 5‐sulfoisophthalic acid sodium) was synthesized and characterized by single‐crystal X‐ray diffraction. Structural determination reveals that the asymmetric unit in 1 contains two crystallographically independent Ba^II atoms. The Ba1 atom is eight‐coordinate with distorted monocapped pentagonal bipyramidal arrangement, whereas the Ba2 atom is ten‐coordinated with bicapped tetragonal prismatic arrangement. The two carboxylate groups of sip^3– adopt different coordination modes, μ₂‐η¹:η¹‐bridging, and μ₂‐η²:η¹‐bridging. The sulfonate group coordinates to three different Ba^II atoms in a tridentate μ₃ mode to generate a ladder‐like one‐dimensional chain. The chains are connected by μ₂‐η¹:η¹‐bridging carboxylate groups to form a wave‐like two‐dimensional network, which are further linked by sip^3– anions to generate a three‐dimensional structure. The thermal stability and luminescence properties of complex 1 were also investigated.     

Synthesis,Crystal Structure,and Properties of a Cadmium(II) Complex with the Flexible Ligand (1′H‐[2, 2′]Biimidazoly‐1‐yl)‐acetic Acid

A novel coordination polymer {[Cd(BDAC)]₂ · H₂O}_n ( 1 ) [HBDAC = (1′H‐[2, 2′]biimidazoly‐1‐yl)‐acetic acid] was synthesized under hydrothermal conditions and characterized by elemental analysis and single‐crystal X‐ray diffraction. Complex 1 crystallizes in the acentric orthorhombic space group Ccc2. The Cd1 atoms and BDAC^2– ligands construct [Cd1(BDAC)] rhomboid grid (4, 4)‐topology layer motifs, whereas the Cd2 atoms and BDAC^2– ligands form [Cd2(BDAC)] 1D coordination polymer ribbons. Furthermore, adjacent lay motifs are linked into 3D net structures by 1D coordination polymer ribbons with 4‐connected 3D trinodal {4²8²10²}{4⁴6²}{4³6²8}₂ topology. The measurement of electric hysteresis loops indicated that complex 1 displays a ferroelectric characteristic.     

Synthesis,Crystal Structure,and Photocatalytic Properties of a Zinc(II) Coordination Polymer Based on 3‐Hydroxy‐2‐pyridinecarboxylic Acid

The zinc(II) compound, [Zn₃(HL)₆]_n ( 1 ) (H₂L = 3‐hydroxypyridine‐2‐carboxylic acid) was synthesized by a solvothermal reaction of Zn(NO₃)₂ · 6H₂O and 3‐hydroxypyridine‐2‐carboxylic acid as raw materials. The structure of complex 1 was determined by single‐crystal X‐ray diffraction analysis and further characterized by elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, as well as powder X‐ray diffraction. X‐ray structure analysis demonstrates that the complex crystallizes in the monoclinic system, space group P2₁/n. There are three zinc ions in the asymmetric unit, which are either five‐coordinate or six‐coordinate. The asymmetric units are further bridged by the carboxylate of the organic ligands, featuring a 2D framework. The solid state diffuse‐reflectance UV/Vis spectra reveals that complex 1 has semiconducting nature with the energy bandgap (E_g) estimated to be 3.11 eV. The photocatalytic properties of complex 1 in degradation of organic dyes were further investigated. Results showed that the complex could degrade 54 % of the dye methylene blue solution within 120 min under UV irradiation light and reused for five times without the decline of the photocatalytic activity.     

Synthesis,Crystal Structure,and Spectral Properties of a Cobalt(II) Complex with N‐Salicylidene‐p‐Toluidine

The complex Co(C₁₄H₁₃NO)₂Cl₂ with the protonated N‐salicylidene‐p‐toluidine ligand was synthesized from an ethanolic solution of CoCl₂·6H₂O and N‐salicylidene‐p‐toluidine. The crystal structure was determined from X‐ray single crystal data (monoclinic, space group Cc, a = 1496.2(3) pm, b = 1257.4(4) pm, c = 1544.6(3) pm, β = 115.01(1)°, Z = 4). Co²⁺ adopts a distorted tetrahedral geometry. The UV‐Vis and IR spectra of the complex are discussed.     

Synthesis,Structure, Antibacterial and Spectroscopic Properties of a Zinc(II) Complex with the Ligand 4‐Heptanoyl‐pyrazol‐5‐one

The long‐chain ligand, 1‐phenyl‐3‐methyl‐4‐heptanoyl‐pyrazol‐5‐one (HL) and its zinc(II) complex ZnL₂ were synthesized. The structure and the properties of ZnL₂ were characterized by elemental analysis, IR spectroscopy, X‐ray diffraction, and thermogravimetric analysis. The zinc ion is five‐coordinated in a square‐pyramidal environment by four oxygen atoms of the HL ligands in the equatorial plane and one water molecule in the axial position. The water molecule is directly bonded to Zn²⁺ and involved in intermolecular hydrogen bonding network. The complex and its corresponding ligand were screened in vitro against some strains of the human pathogenic bacteria. The metal complex exhibits higher antibacterial activity than its corresponding ligand. The complex exhibits purple effect emission as the result of fluorescence from the intraligand emission excited state.     

Synthesis,Crystal Structures,and Luminescent Properties of Two Complexes based on 5‐tert‐Butylisophthalic Acid and 1, 2‐Bis(4‐pyridyl) Ethane

Abstract. Two coordination polymers, namely, [Zn(bpe)_0.5(Htbip)(tbip)_0.5] · H₂O ( 1 ) and [Cd(bpe)_0.5(tbip)] ( 2 ) [H₂tbip = 5‐tert‐butylisophthalic acid and bpe = 1, 2‐ bis(4‐pyridyl) ethane] were synthesized through hydrothermal reactions. Single‐crystal X‐ray diffraction analysis reveals that complex 1 presents a three‐dimensional (3D) six‐connected uninodal structure with the type of topology of svi‐x/I4/mcm → Ibam, whereas complex 2 holds a 2D 4⁴‐sql layer structure. Moreover, the photoluminescent properties of the complexes at room temperature were investigated.     

Synthesis and Luminescent Properties of Two Zinc(II) Coordination Polymers Constructed by 4‐(Pyridin‐4‐ylmethoxy)benzolic Acid Ligand

Two coordination polymers, namely [Zn(L)Cl] ( 1 ) and [Zn(L)₂] ( 2 ) [L = 4‐(pyridin‐4‐ylmethoxy)benzolic acid] were synthesized under hydrothermal conditions and characterized by single‐crystal X‐ray diffraction analyses, powder X‐ray diffraction, and thermogravimetric analysis. Compounds 1 and 2 have a two‐dimensional square‐shaped structure (the dimensions are 15.43 × 15.43 Å for 1 and 12.064 × 15.017 Å for 2 ) with (4⁴ · 6²) topology. Moreover, compounds 1 and 2 exhibit a 3D supramolecular structure made up by strong π–π interactions from the adjacent layers. Furthermore, compounds 1 and 2 show good fluorescence properties in the solid state at room temperature.     

Synthesis,Characterization, and Crystal Structure of Thallium(I) Complex containing Monodeprotonated 2,6‐Pyridinedicarboxylic Acid

The reaction of an ethanolic solution 2,6‐pyridinedicarboxylic acid ( 1 , LH₂) with TlNO₃ in the presence of triethylamine led to the coordination polymer [Tl(LH)]_n ( 2 ). The complex was characterized by elemental analysis, IR spectroscopy and single‐crystal X‐ray diffraction. Crystal data for 2 at –80 °C: monoclinic, space group I2/a, a = 696.1(1), b = 1190.6(2), c = 931.0(2) pm, β = 103.28(1)°, Z = 4, R₁ = 0.0256.     

Synthesis,Characterization, and Crystal Structure of a Chromium(III)‐Complex Containing 2,6‐Pyridinedicarboxylic Acid and 1,10‐Phenanthroline

The reaction of solution 2,6‐pyridinedicarboxylic acid and 1,10‐phenanthroline ( 1 ) with CrCl₃·6H₂O led to the complex [Cr(phen)(pydc)(H₂O)][Cr(pydc)₂]·4H₂O ( 2 ) (phen is 1,10‐phenanthroline and pydcH₂ is 2,6‐pyridinedicarboxylic acid). 2 was characterized by elemental analysis, IR spectroscopy and single‐crystal structure determination. Crystal data for 2 at ?80 °C: triclinic, space group , a = 818.5(1), b = 1492.2(1), c = 1533.6(2) pm, α = 76.45(1)°, β = 84.22(1)°, γ = 77.99(1)°, Z = 2, R₁ = 0.0416.     

Synthesis, Structure and Physical Properties of a Barium（II） Complex with 5-Sulfoisophthalic Acid Sodium

An alkaline earth metal-organic framework [Ba(Hsip)(H2O)4]n (1, NaH2sip = 5-sulfoisophthalic acid sodium) has been constructed, and characterized by single-crystal X-ray diffraction. In complex 1, each Ba(II) atom coordinates to one ligand Hsip3- and four water molecules with a distorted nine-coordinated monocapped tetragonal antiprism geometry. Each Hsip2- anion acts as a μ3-bridging ligand, in which two carboxylate groups adopt the same bidentate chelating coordinating model and the sulfonate group takes a monodentate coordinating model, resulting in a wave-like two-dimensional network with a (6, 3) topological structure. The two-dimensional networks are further linked by O-H···O to form a three-dimensional structure. Luminescent property and thermal stability of complex 1 are investigated. 1 belongs to the orthorhombic system, space group Pna21 with a = 7.3333(2), b = 16.7044(3), c = 10.4817(2), Z = 4, V = 1283.99(5)3, Mr = 453.58, Dc = 2.346 g/cm3, F(000) = 880, μ = 3.314 mm-1, the final R = 0.0261 and wR = 0.0592 for 2425 observed reflections with I > 2σ(I).     

Synthesis,Crystal Structure and Spectroscopic Properties of Bis(1‐(E)‐2‐formylpyridine semicarbazone)nickel(II) Diperchlorate Monohydrate

Pale‐green crystals of the title complex were prepared by reaction of 2‐formylpyridine semicarbazone (HCSpy) and nickel(II) perchlorate in boiling ethanol. The crystals are triclinic with the nickel ion in an octahedral arrangement, coordinated by two nitrogen atoms and one oxygen donor atom from each ligand molecule. The effect of coordination on bond lengths and angles was explored by comparison with the single‐crystal structure data of the free ligand HSCpy, which was collected as well. The assumed coordination mode was supported by ¹H and ¹³C NMR spectroscopic data. A detailed analysis of the electronic properties, including semi‐empirical quantummechanical calculations is presented. Furthermore, the data obtained from magnetic susceptibility and EPR measurements are in accordance with a low‐spin d⁸ nickel(II) complex.     

Synthesis,Characterization, and Crystal Structure of a New Coordination Polymer of Lead(II) Containing 2,6‐Pyridinedicarboxylic Acid

The reaction of solution 2,6‐pyridinedicarboxylic acid ( 1 ) and 2,2′‐Bipyridine with Pb(NO₃)₂ led to the coordination polymer [Pb(pydc)]_n ( 2 ) (pydcH₂ is 2,6‐pyridinedicarboxylic acid). This complex was characterized by elemental analysis, IR spectroscopy and single‐crystal structure of 2 . Crystal data for 2 at ?80 °C: monoclinic, space group P2₁/n, a = 977.2(1), b = 554.0(1), c = 1425.3(2) pm, β = 104.75(1)°, Z = 4, R₁= 0.0261. The units [Pb(pydc)] form infinite chains along [010].     

Synthesis,Characterization, and Luminescence of Two New Zinc(II) Coordination Polymers Constructed by 5‐(4‐Carboxybenzyloxy)Isophthalic Acid Ligand

Two coordination polymers, namely Zn(HL)(4,4′‐bpy)_1.5 ( 1 ), [Zn₃(L)₂(BIMB)₂] · 5H₂O ( 2 ) [H₃L = 5‐(4‐carboxybenzyloxy)isophthalic acid, 4,4′‐bpy = 4,4′‐bipyridine, BIMB = 1,4‐bis(1H‐imidazol‐1‐yl)benzene] were synthesized under hydrothermal conditions. Their structures are determined by single‐crystal X‐ray diffraction analyses and further characterized by elemental analyses, IR spectroscopy, and thermogravimetric (TG) analyses. Complex 1 features a 2D 4‐connected network. Complex 2 is a 3D twofold interpenetrating (3,4,6)‐connected net. In addition, the luminescent properties for 1 and 2 were studied in the solid state at room temperature.     

Magnesium(II), Calcium(II), and Barium(II) Coordination Compounds Constructed by 1H‐Tetrazolate‐5‐acetic Acid Ligand

Reactions of H₂tza (H₂tza = 1H‐tetrazolate‐5‐acetic acid) with Mg(NO₃)₂ · 6H₂O, Ca(NO₃)₂ · 4H₂O, or Ba(NO₃)₂ with the presence of KOH under hydrothermal conditions, produced three new coordination compounds, [M(tza)(H₂O)₂] (M = Mg ( 1 ), Ca ( 2 ), Ba ( 3 )). These compounds were structurally characterized by elemental analysis, IR spectroscopy, and single‐crystal X‐ray diffraction. Compounds 1 and 3 display 2D structures, whereas 2 reveals a 1D structure with bridging tza ligand molecules as linkers. Furthermore, the luminescence properties of 1 – 3 at room temperature in the solid state were also investigated. The results show that the nature of metal ions play an important role in governing the molecular frameworks of 1 – 3 , and the strong coordinate abilities of carboxylate and tetrazolate group, endow tza with abundant coordination modes.     

Syntheses,Crystal Structures,and Luminescence Properties of Dinuclear Metal (Ag+ and Cu+) Complexes with the Ligand 2‐MTPP [2‐MTPP = 2‐(Methylthio)‐4‐(pyridin‐2‐yl)pyrimidine]

Reactions of the ligand 2 ‐ MTPP [2‐MTPP = 2‐(methylthio)‐4‐(pyridin‐2‐yl)pyrimidine] with AgNO₃ and CuI produced dinuclear silver(I) ( 1 ) and copper(I) ( 2 ) complexes, respectively. Both complexes adopt a chair‐like structure in which two 2 ‐ MTPP ligands and two metal ions are joined together through M–N and M–S coordination bonds. The luminescence properties of both complexes were investigated in solid state at room temperature.     

Crystal Structures and Photoluminescence Properties of Zinc(II) and Cadmium(II) Coordination Polymers with “Y”‐Shaped Ligands

Three Zn^II and Cd^II complexes with Y‐shaped dicarboxylate ligands, namely [Zn(L₁)(2,2′‐bpy)₂(H₂O)] · 2H₂O ( 1 ), [Zn(L₁)(bpp)(H₂O)] ( 2 ), and [Cd(L₁)(H₂O)] · H₂O ( 3 ) [H₂L₁ = N‐phenyliminodiacetic acid, 2,2′‐bpy = 2,2′‐bipyridine, bpp = 1,3‐bis(4‐pyridyl)propane] were synthesized and characterized by elemental analysis, IR spectroscopy single‐crystal X‐ray diffraction, and thermogravimetric analyses. Compound 1 shows an hydrogen‐bonded 2D network, whereas compound 2 is an infinite 1D wavy chain structure, though O–H ··· O hydrogen‐bonded to form a 2D network. Compound 3 displays a 2D uninodal 3‐connected Shubnikov plane net with the point symbol of (4.8²). Moreover, the solid‐state such as thermal stabilities and fluorescence properties of 1 – 3 were also investigated.     

Synthesis,Crystal Structure,and Emission Spectra of Lanthanum(III) Coordination Polymer with 1,5‐Naphthalenedisulfonate Ligand

The first two‐dimensional lanthanum(III) coordination polymer, [La(1,5‐NDS)_1.5(H₂O)₅]_n (1) (1,5‐NDS^2? = 1,5‐naphthalenedisulfonate), was synthesized and structurally characterized by single‐crystal X‐ray diffraction analysis. The disulfonate ligands act in the η¹:η¹:μ₂ and η¹:η¹:η¹:μ₃ binding modes to link the LaO₉ tricapped trigonal prisms into a lamellar structure. It exhibits strong purple emission in the solid state.     

(Ba6O)(ReN3)2: Synthesis,Crystal Structure and Physical Properties

The reaction of a mixture of barium and rhenium (3:1) at 850 °C under flowing nitrogen yielded the nitride‐oxide (Ba₆O)(ReN₃)₂ (R (No. 148); a = 8.1178(2) Å, c = 17.5651(4) Å; V = 1002.43(5) Å³; Z = 6). According to a structure refinement on X‐ray powder diffraction data, this compound is isostructural to a recently described nitride‐oxide of osmium of analogous composition. The structure consists of sheets of trigonal ReN₃ units and trigonal antiprismatic Ba₆O groups. The Ba–O distance of 2.73 Å is close to the sum of the respective ionic radii. The trigonal ReN₃^5– nitride anion displays a Re–N bond length of 1.94 Å, and is planar within the limits of experimental error. The constitution of the anion was confirmed by IR and Raman spectroscopy. The nitride‐oxide is stable up to 1000 °C, semiconducting (σ = 4.57 × 10^–3 Ω^–1 · cm^–1 at RT), and paramagnetic down to 25 K. A Curie–Weiss analysis resulted in a magnetic moment of μ = 0.68 μ_B per rhenium atom.     

Synthesis,Structures, and Luminescent Properties of Three Alkaline Earth Metal‐based MOFs Assembled from 3‐(3‐Carboxyphenoxy) Phthalic Acid Ligand

Three two‐dimensional (2D) coordination complexes, namely [Ca₂(HL)₂(H₂O)₅]_n · 2nH₂O ( 1 ), [Sr(HL)(H₂O)₃]_n · nH₂O ( 2 ), and [Ba(HL)(H₂O)₃]_n · nH₂O ( 3 ) [H₃L = 3‐(3‐carboxy‐phenoxy) phthalic acid], were synthesized by using the ligand H₃L and alkaline earth metals. Structural analysis reveals that the structures of complexes 1 – 3 can be described as 2D networks with the point (Schälfli) symbol for net: {3¹² · 4¹⁴ · 5²} topology. Additionally, the thermal stability and solid‐state luminescent properties of compounds 1 – 3 were investigated at room temperature. The quantum yield (QY) of compound 2 is 10.75 %, which is much higher than the QY of the free H₃L ligand (QY_H3L < 1 %).