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In the title complex, [Zn(C15H10ClN3)2](CF3SO3)2, the ZnII metal center is sixfold coordinated by three nitrogen atoms of each 4-chloroterpyridine ligand in a distorted octahedral geometry with triflouromethanesulfonate ions completing the outer coordination sphere of the complex. π–π stacking interactions between the pyridyl rings in adjacent molecules contribute to the alignment of the complexes in layers along the c axis.

Schiff bases are considered as privileged ligand in coordination chemistry as they easily form stable complexes with most transition metal complexes. In this paper, a novel Schiff-base ligand derived from Curcumin and Semicarbazide (HMHC) and its transition metal [Mn(II), Co(II), Ni(II), Cu(II) and Zn(II)] complexes were synthesized. FT-IR, UV–Vis, NMR, Mass, TG-DTA and ESR spectral techniques were used to confirm the structures of the metal chelates and ligand. The Schiff base behaves as a tridentate ligand with O and N donors and coordinates to metal ion via phenolic oxygens and azomethine nitrogen. The compositions of the ligand and its metal complexes have been established by elemental analysis. Spectral investigations suggested octahedral geometrical arrangement for all the metal(II) complexes, having 2:1 (L:M) stoichiometric ratio of the type [M(HMHC)2]H2O. The Schiff base ligand and its metal complexes have been screened for antimicrobial evaluation towards some clinically important microorganisms. Result found that the metal complexes were more active than the ligand. Also anti-inflammatory activity of Schiff base complexes were studied by protein denaturation method and result reveals that Zn(II) complex shows more activity.

Iron(II)-Schiff base complexes are a well-studied class of spin-crossover (SCO) active species due to their ability to interconvert between a paramagnetic high spin-state (HS, S = 2, 5T2) and a diamagnetic low spin-state (LS, S = 0, 1A1) by external stimuli under an appropriate ligand field. We have synthesized two mononuclear FeII complexes, viz., [Fe(L1)2](ClO4)2.CH3OH (1) and [Fe(L2)2](ClO4)2.2CH3CN (2), from two N6–coordinating tridentate Schiff bases derived from 2,6-bis[(benzylimino)methyl]pyridine. The complexes have been characterized by elemental analysis, electrospray ionization–mass spectrometry (ESI-MS), Fourier-transform infrared spectroscopy (FTIR), solution state nuclear magnetic resonance spectroscopy, 1H and 13C NMR (both theoretically and experimentally), single-crystal diffraction and magnetic susceptibility studies. The structural, spectroscopic and magnetic investigations revealed that 1 and 2 are with Fe–N6 distorted octahedral coordination geometry and remain locked in LS state throughout the measured temperature range from 5–350 K.

The sand, silt, shale and clay fractions soils derived from Maastrichtian sediments in the Afikpo Basin, southeastern Nigeria exhibit unusually high cation-exchange capacities. Smectite was identified by X-ray diffraction in all sample fractions and was selectively dissolved by treatment with 1HCl and 0.5 NaOH. Structural formulae, based on chemical analysis of the dissolved material, suggest that the smectite is intermediate in composition between a di- and a trioctahedral mineral and that the octahedral cation occupancy, together with the number of Mg and Fe atoms per unit cell, decreases with decrease in particle size of the soil fraction examined. The mean formula for the smectite in the clay separate is: [(M+= 0.40, Si = 3.33, Al = 0.67), (Al = 1.07, Fe2+= 0.09, Fe3+= 0.41, Mg = 0.82)] O10(OH)2. Similar analysis of smectite present in clay-size material separate from weathered granitic rock taken from the bases of the soilprofiles showed that it had close to the full trioctahedral inherited from the weathered granites.The clay mineralogy of the soils was affected by inherited smectite, probably of hydrothermal of deuteric origin. This mineral is unstable in the soil environment and, although its alteration products are fairly uniform in composition. Keywords: Dissolution, Granitic, Octahedral, Smectite, Soil

?? ????? ?????????? (2Z)-1-benzoyl-3-(2-hydroxyphenyl)-5-phenylformazan ?? ?????? ????? ???????????? ?? ????? ?? (E)-N?-(2-hydroxybenzylidene)benzohydrazide ??? ????? ?????? ?????????? ?? ??????? ??????? ??????? ??????? ???, ???? ?????????? ?????? ???????? ???????? ??? ?????? ??? ??????? (IR) ?(1H-NMR) ?(Mass) ?????????? ??????????. ??? ????????? ?? ??????? ???? ?????? ??????? ?? ??????? ??????? ???????? ????? ????????? ???? ?????? CPE. ???? ????? ?????? ?????? ????????? ?? ????? ????? ?????????? ????? ??????? ???? ??????? ?????? HCl ?????? ??? ???? ???? ????? (D) ????? ????? ????????? ????? ???? ????? ?????????? (5*10-4) ????? ??????? 850C ???? ??????? 25min ?????? HCl 0.1M

?? ????? ?????????? (2Z)-1-benzoyl-3-(2-hydroxyphenyl)-5-phenylformazan ?? ?????? ????? ???????????? ?? ????? ?? (E)-N?-(2-hydroxybenzylidene)benzohydrazide ??? ????? ?????? ?????????? ?? ??????? ??????? ??????? ??????? ???, ???? ?????????? ?????? ???????? ???????? ??? ?????? ??? ??????? (IR) ?(1H-NMR) ?(Mass) ?????????? ??????????. ??? ????????? ?? ??????? ???? ?????? ??????? ?? ??????? ??????? ???????? ????? ????????? ???? ?????? CPE. ???? ????? ?????? ?????? ????????? ?? ????? ????? ?????????? ????? ??????? ???? ??????? ?????? HCl ?????? ??? ???? ???? ????? (D) ????? ????? ????????? ????? ???? ????? ?????????? (5*10-4) ????? ??????? 850C ???? ??????? 25min ?????? HCl 0.1M

تم تحضير الفورمازان (2Z)-1-benzoyl-3-(2-hydroxyphenyl)-5-phenylformazan من ازدواج املاح الدايازونيوم مع قاعدة شف (E)-N′-(2-hydroxybenzylidene)benzohydrazide وتم تحضير معقدات الفورمازان من التفاعل المباشر للاملاح الفلزية معة, وشخص الفورمازان المحضر ومعقداته باستخدام طيف الاشعة تحت الحمراء (IR) و(1H-NMR) و(Mass) والتوصيلية الكهربائية. وتم استخدامها في استخلاص ايون الكروم الرباعي من محاليلة المائية باستخدام طريقة الاستخلاص نقطة الغيمة CPE. وتمت دراسة الظروف المثلى للاستخلاص من تاثير تركيز الفورمازان ودرجة الحرارة وزمن التسخين وتركيز HCl للوصول الى افضل نسبة توزيع (D) ونسبة مئوية للاستخلاص عندما يكون تركيز الفورمازان (5*10-4) ودرجة الحرارة 850C وزمن التسخين 25min وتركيز HCl 0.1M

Three new adducts have been synthesized and studied by infrared and NMR spectroscopies. The suggested structures are discrete with a pyridine -3- sulfonate acting as a tri O-chelating and N-donor or as a non σ coordinating ligand, a 4-aminobenzenesulfonate behaving as a monodentate O-donor, the environments around the tin centre being tetrahedral, octahedral or seven coordinated. In all the studied compounds, supramolecular architectures are obtained when hydrogen bonds are considered.

The proposed structures for the studied adducts - DABCO.3[NiCl2·2H2O].EtOH and 2DABCO.3CuCl2.4EtOH or 3DABCO. 4CuCl2.5EtOH are discrete with two or three metallic components, the environments around the Nickel centres being octahedral or square planar, while being octahedral , linear or a square based prism around the Copper centres, the DABCO behaving as a monodentate or bridging bidentate ligand or being lattice. Extra intermolecular interactions via hydrogen bonds when considered, may lead to supramolecular architectures.

When the diphenic acid HO2CC6H4C6H4CO2H is allowed to react with SnBu2Cl2 or SnPh3OH, HO2CC6H4C6H4CO2. SnBu2Cl (A) and O2CC6H4C6H4CO2(SnPh3)2∙4H2O(B) were obtained and characterized by infrared spectroscopy. The structures are an infinite chain or an oligomer, the diphenic anion being a monodentate or a monochelating ligand. The environment around the tin centers is trigonal bipyramidal or octahedral.

Four new di- and triorganonitrato stannate complexes and related derivatives have been synthesized and characterized by infrared and Mössbauer spectroscopy. The structure of Et4N[NO3(SnClPh3)2(SnPh3NO3)] (1) has been determined by single-crystal X-ray diffraction analysis. In the trinuclear organostannate complex, each SnIV atom is five-coordinated and adopts a trigonal-bipyramidal trans-OXSnC3 (X=O or Cl) geometry. The overall coordination environment of the SnIV atoms is trans-octahedral for 2 and 3 or cis-trigonal-bipyramidal for 4. In the related derivatives, the NO3- anions behave as monodentate ligands.

Three isomers of [Cu(pn)2Cl2] in solid state have been synthesized, isolated and characterized by elemental analysis, molar conductance, FTIR, TGA, EPR, electronic spectra and DFT calculation. The molar conductance of 1 mM solution of the complexes measured in DMSO falls in 40–44 Scm2 mol−1. All the isomers in aqueous medium show similar absorption pattern in the UV–visible region of the spectra. They are nearly identical in solution although in the solid state they exist in three distinct colors. The change in the color of complexes is due to change in conformations of the propanediamine molecule. Cu(II) in [Cu(pn)2Cl2] lies on an inversion center. It is octahedrally coordinated to four nitrogen of 1,3-diaminopropane (pn) and two chloride ions displaying three different spatial conformations namely chair–chair, chair–boat and boat–boat. The TGA of the complexes suggest that Cu is left as final residue at 600 °C. The entire data have been supported by DFT calculation.

A biodegradable polymer was synthesized by the modification reaction of polymeric starch with thiourea which is further modified by transition metals, Mn(II), Co(II), Ni(II), Cu(II) and Zn(II). All the polymeric compounds were characterized by (FT-IR) spectroscopy, 1H NMR spectroscopy, 13C NMR spectroscopy, UV–visible spectra, magnetic moment measurements, thermogravimetric analysis (TGA) and antibacterial activities. Polymer complexes of Mn(II), Co(II) and Ni(II) show octahedral geometry, while polymer complexes of Cu(II) and Zn(II) show square planar and tetrahedral geometry, respectively. The TGA revealed that all the polymer metal complexes are more thermally stable than their parental ligand. In addition, biodegradable studies of all the polymeric compounds were also carried out through ASTM-D-5338-93 standards of biodegradable polymers by CO2 evolution method which says that coordination decreases biodegradability. The antibacterial activity was screened with the agar well diffusion method against some selected microorganisms. Among all the complexes, the antibacterial activity of the Cu(II) polymer–metal complex showed the highest zone of inhibition because of its higher stability constant.

A multidentate ligand, 3,4-bis(2-iminomethylphenol)-2,2’:5,2’’-terthiophene (L), has been synthesized by the condensation of 3,4-diamino-2,2’:5,2’’-terthiophene and salicylaldehyde. The ligand and Ni(II) and Zn(II) complexes were synthesized and characterized by IR, NMR, UV-Vis, AAS, MS, molar conductivity and magnetic susceptibility measurements. The ligand behaves as neutral ONS-ONS bis-chelant towards Ni(II) in [Ni2LCl4(H2O)2]4H2O and as dibasic ONNO donor towards Zn(II) in [ZnL(NH3)2]. The dinuclear Ni(II) complex exhibits subnormal magnetic moment at room temperature due to metal-metal interaction through extended conjugation. The participation of the ring sulfur in bonding towards Ni(II) and the non-participation of the same towards Zn(II) are notable features. Octahedral geometries are proposed for both complexes. Cyclic voltammetric studies revealed electrochemical polymerization of the free ligand (L) but not of the Ni(II) and Zn(II) complexes.