michal dusek

A new complex with the formula [NiL2] (a) was synthesized. L is Schiff base ligand and HL is identified as N-(2-hydroxy-1-naphthylidene)-2-methyl aniline. The compound was characterized by FT-IR, UV-Vis, elemental analysis, and crystal X-ray diffraction methods. The X-ray diffraction results confirmed that [NiL2] (a) adopts a regular square-planar geometry. The interactions of complex (a) with FS-DNA (salmon sperm DNA) have been studied using UV–Vis, fluorescence spectroscopies and Gel electrophoresis. The binding constant (Kb), and the apparent bio molecular quenching constant (kq) for FS-DNA were obtained through Stern–Volmer equation. Thermodynamic parameters data (∆H°, ΔS° and ΔG°) showed that hydrogen bonding and van der Waals interactions have an important function in the interaction of the DNA–Ni(II) complex and the binding mode is the groove binding. This dual finding highlights the complex's nuanced influence on DNA structure and emphasizes the importance of using multiple analytical techniques to fully understand metal-DNA interactions.

Transition metal ions have been extensively studied for the removal of heavy metal ions as efficient adsorbent from aqueous solution. In this work, Fe2O3 nanoparticles were synthesized by thermal decomposition route of FeSO4.4H2O at the presence of urea (1:1 molar ratio) at two different temperatures (500 °C and 600 °C) and characterized by XRD and TEM. The XRD result show that single-phase of α-Fe2O3 was prepared by increasing of calcination temperature from 500 °C to 600 °C. TEM images confirmed that the as-prepared products have a different shapes and that particle sizes are in the range of tens nanometers. The average crystallite size of pure α-Fe2O3 calculated from XRD pattern was 53.1 nm and 41 nm, respectively, depending on the method employed. In addition, Pb(II) adsorption has been studied and considered as a function of pH solution, contact time, initial Pb(II) concentration and also adsorbent dosage. The adsorption results show that the iron oxides were able to high percentage remove Pb(II) by increasing of contact time, adsorbent dosage and initial Pb(II) ion. The pH solution of 6 proved to be the most suitable for the removal of Pb(II).

In this paper, we report a simple and convenient method for the synthesis of α‑Fe2O3 nanoparticles via hydrothermal process followed by thermal decomposition using the new iron precursor, which was obtained by mixing of benzoic acid (BA) and Fe(NO3)3∙3H2O in water as solvent. Two products with almost similar morphologies and sizes were obtained by changing the calcination temperature (500 and 600ºC) for 2 h in the air atmosphere. They were named as Fe‑500 and Fe‑600, respectively, and characterized by Fourier transform infrared (FT‑IR) and ultraviolet‑visible (UV‑Vis) spectroscopy, X-ray powder diffraction (XRD), Energy dispersive spectroscopy (EDS) and transmission electron microscopy (TEM). FT‑IR, UV‑Vis, XRD and EDS results confirm the formation of α‑Fe2O3 phase. Also, TEM images confirm that the size of the products is less than 100 nm.

A new 1D copper(I) coordination polymer [Cu2(μ-L)(μ-I)2]n (1), where L is N,N'-bis(4-nitrobenzylidene)butane-1,4-diamine, was synthesized and characterized by CHN, FT-IR, 1H NMR, and single-crystal X-ray analyses. Based on X-ray results, this new compound crystallizes in a monoclinic system with space group P21/c. The asymmetric unit consists of one copper and one iodine atoms and half of the Schiff base ligand (L). The flexible Schiff base compound is coordinated to copper(I) ion as a bis-monodentate ligand. The coordination geometry around the copper(I) ions is distorted trigonal planar. The thermal behavior of 1 was studied using thermogravimetry analysis. Moreover, the nanoparticles of 1 were prepared via the ultrasonic-assisted method and characterized by XRD and SEM analyses.

Two new mercury(II) Schiff base complexes [Hg((2,6-Cl-ba)2-1,2-pn)X2] (X = Cl (1), I (2) and (2,6-Cl-ba)2-1,2-pn = N,N'-bis(2,6-dichlorobenzylidene)-1,2-diaminopropane) have been synthesized and characterized by elemental analysis (CHN), FT-IR and 1H-NMR spectroscopy. The crystal structure of complexes 1 and 2 were determined by single-crystal X-ray diffraction. X-ray results shown that the mercury(II) ions in these complexes have a distorted tetrahedral geometry with HgN2Cl2 and HgN2I2 chromophores, respectively. In these complexes, the Schiff base ligand (2,6-Cl-ba)2-1,2-pn act as chelating bidentate ligand, coordinating via the two iminic nitrogen atoms and it adopts an E,E conformation. Finally, the thermal behavior of complexes was study using thermogravimetry in order to evaluate their thermal stability and thermal decomposition pathway.

Thiosemicarbazone ligand 4Hbatsc = 4-hydroxybenzaldehyde-thiosemicarbazone and its silver(I) complex [Ag(PPh3)3(4Hbatsc)]NO3 were synthesized and characterized by elemental analysis (CHN), FT-IR spectroscopy, and single-crystal X-ray diffraction. The triclinic unit cell of 4H-ba-tsc (space group P-1) contains two independent molecules. Each of the two independent molecules is almost planar, with the sulfur atom (S1/S2) and the hydrazine nitrogen atom (N6/N4) in the E position concerning the C3-N5/C4-N4. The title complex is a triclinic P-1 mononuclear complex with the silver(I) ion coordinated in a distorted tetrahedral geometry by one S atom of 4H-ba-tsc and three P atoms of three PPh3. The complex involves the 4H-ba-tsc thiosemicarbazone ligand in an S monodentate binding mode. Besides, the thermal behavior of the complex was studied using thermogravimetry in order to evaluate its thermal stability and thermal decomposition pathway. Finally, nanoparticles of the complex were prepared in an ultrasonic bath.

In this work, pyridine 4-carbaldehye semicarbazone Schiff base ligand (HL) was synthesized with condention of pyridine 4-carbaldehyde and semicarbazide hydrochloride in reflux method. The HL was characterized using the CHN elemental analysis, FT-IR, UV-Vis, and 1H NMR spectroscopy. The single crystals of HL prepared and used for the X-ray crystallography. Single-crystal X-ray diffraction revealed that, HL crystallized in a triclinic system with the space group P-1. The FT-IR spectra and X-ray crystallography results suggested that the HL ligand is in keto form.

New dinuclear methoxo-bridged manganese(III) complex [Mn2((MeO-bph)en)2Cl2(m-CH3O)2] (1) was synthesized by template reaction of 2-hydroxy-4-methoxybenzophenone, 1,2-ethanediamine and MnCl2×6H2O with molar ration (1:1:1) in methanol as solvent. The title compound 1 was characterized by elemental analyses (CHN), Fourier Transform infrared spectroscopy (FT-IR) and single crystal X-ray diffraction. X-ray result reveal that 1 is dimeric with methoxo bridges between two symmetry equivalent manganese ions. The Mn ions are surrounded in a distorted octahedral geometry influenced by Jahn-Teller effect. The tridentate Schiff base ligand MeO-bp-en and one of the methoxo-bridges bind in the equatorial mode, whereas in the axial positions, other metoxo-bridge and Cl atom bind to the Mn ions. Thermogravimetric analysis of 1 was studied and display the title compound 1 decompose in three stages. Finally, by calcination of 1 at 500 °C for 3 h, we prepared Mn2O3 particles and characterized by FT-IR, XRD and SEM.

In this study, the reaction of 4-methoxy-2-hydroxybenzophenone (HL) with copper(II) nitrate three hydrate in a 1:2 molar ratio in methanol as solvent resulted in the formation of the complex CuL2. In order to prepare a suitable single crystal, slow evaporation technique was used, while for preparing complex nanoparticles, assisted ultrasound was used. Crystal structure of CuL2 was determined by single crystal X-ray diffraction. A square-planar geometry was found for CuL2. Finally, the complex was calcinated at 600 °C for 2.5 h. The final residue was CuO nanoparticles which were characterized by SEM and XRD. There is no peak for impurity in the XRD pattern. In this study, the reaction of 4-methoxy-2-hydroxybenzophenone (HL) with copper(II) nitrate three hydrate in a 1:2 molar ratio in methanol as solvent resulted in the formation of the complex CuL2. In order to prepare a suitable single crystal, slow evaporation technique was used, while for preparing complex nanoparticles, assisted ultrasound was used. Crystal structure of CuL2 was determined by single crystal X-ray diffraction. A square-planar geometry was found for CuL2. Finally, the complex was calcinated at 600 °C for 2.5 h. The final residue was CuO nanoparticles which were characterized by SEM and XRD. There is no peak for impurity in the XRD pattern.

Vanadium(IV) complex [VO((MeO-bph)2en)] (1), (MeO-bph)2en=N,N¢-bis(2-hydroxy-4-methoxybenzophenone)-1,2-ethanediamine, was synthesized and characterized by elemental analyses (CHN), FT-IR spectroscopy, thermogravimetry, SEM and single crystal X-ray diffraction. The title complex 1 was prepared by the reaction of VO(acac)2, 1,2-ethanediamine and 2-hydroxy-4-methoxybenzophenone (molar ratio 1:1:2). The single-crystal X-ray analysis of 1 shows that the vanadium(IV) ion is located in a distorted square pyramid (N2O3) environment with the tetradentate Schiff base ligand coordinated in equatorial positions and one oxygen atom in the axial position. Thermogravimetric analysis shows that the complex 1 decomposes in two stages. Finally, the complex was calcinated at 500 °C for 3 h and the V2O5 products characterized by FT-IR and SEM.

In this paper, we report the syntheses and crystal structuredetermination of three mononuclear and four-coordinated zinc(II) bromide complexes with chemical formula of [Zn(tsc)2]Br2 (1), Zn(PPh3)2Br2 (2) and Zn(Brcatsc)Br2 (3). The synthesized complexes are characterized by elemental analysis (CHN) and theircrystal structures are investigated by single crystal X-ray diffraction. In complex 1, the TSC coordinates to the zinc(II) ion as a bidentate ligand via N and S atoms. In complex 3, the thiosemicarbazone ligand Brcatsc coordinates to zinc(II) ion as a monodentate ligand via S atom. In these complexes, the zinc(II) ion coordinated in a distorted tetrahedral coordination geometry.

Nano-sized powder of a new 1D copper(I) coordination polymer, [Cu(nba2en)(NCS)]n (1), (nba2en = N,Nʹ-bis(4-ntrobenzylidene)ethane-1,2-diamine, was synthesized using ultrasonic bath assisted and characterized by scanning electron microscopy (SEM), IR and 1H-NMR spectroscopy, and elemental analyses. Thermal stability of 1 was studied using thermogravimetric (TG) and differential thermal analyses (DTA). The crystal structure was investigated by single-crystal X-ray diffraction. The structure of 1 consists of a 1D polymeric chain in which copper(I) ions are bridged by two thiocyanate group bonding in an end-to-end fashion, with CuCu separation 5.556(4) Å.

Nanoparticles of a new dinuclear silver(I) complex [Ag2(PPh3)2(μ-S-4nb-tsc)2(η1-S-4nb-tsc)2](NO3)2, where 4nb-tsc = 4-nitrobenzylidenethiosemicarbazone and PPh3 = triphenylphosphine, were prepared in an ultrasonic bath and characterized by FT-IR and SEM. The crystal structure of a suitable single crystal prepared by slow evaporation was determined by single crystal X-ray diffraction. The compound crystallized in the triclinic system with space group P-1 and Z = 2. X-ray results showed that the neutral thiosemicarbazone ligand 4nb-tsc was coordinated to silver(I) ion in two different bonding modes, μ-S, and η1-S. The shortest distance between the sulfur-bridged Ag cations was 3.576(5) Å. One P atom and three S atoms from three 4nb-tsc ligands coordinated to the silver(I) ion in a distorted tetrahedral geometry. In the crystal packing of the title compound, several hydrogen bonds were connecting the molecules of the complex.

[Pb(gly)2]n (1) (gly is the abbreviation of Glycine) have been synthesized and characterized by elemental analyses, IR, 1H NMR and 13C NMR spectroscopy. The single crystal structure of 1 show the complex is 2D coordination polymer with octahedral environment that is formed into 3D supramolecule through hydrogen bond. Structural determination of compound 1 reveals the Pb(II) ion is four coordinated, bonded to a nitrogen, oxygen and two carbon atoms from the Glycine ligand.The crystal structure of compound 1 consists of a 3D supramolecular compound and shows the coordination number in the Pb(II) ions is six. PbO nanoparticles were synthesized by calcination of compound 1 at 500, 550 and 600 °C under air atmosphere. Calcination of the compound 1 at these temperatures yields mixture of orthorhombic and tetragonal PbO nanoparticles and nanorods. The PbO nanostructure was characterized by scanning electron microscopy (SEM) and X-ray powder diffraction (XRD). The thermal stability of compound 1 was studied by thermal gravimetric (TG) and differential thermal analyses (DTA).

A new tetradentate N2O2 Schiff base ligand (MeO-bph)2bn = N,N¢-bis(2-hydroxy-4-methoxybenzophenone)-1,4-butanediamine was prepared from the condensation of butane-1,4-diamine with 4-methoxy-2-hydroxybenzophenone and characterized by 1H-NMR spectroscopy and single-crystal X-ray diffraction. Its nickel(II) and copper(II) complexes characterized using elemental analyses (CHN) and IR spectroscopy. Thermogravimetric analysis of the Schiff base ligand and its Ni(II) and Cu(II) complexes revealed their thermal stability and decomposition pattern. Finally, the complexes were used for the preparation of NiO and CuO nanoparticles by solid-state thermal decomposition. The nanoparticles were characterized by FT-IR, XRD, and SEM. FT-IR and XRD confirmed the purity of the formed products NiO and CuO.

New Schiff-base compounds N-(3,4-dimethoxybenzylidene)-4-methoxyaniline (1) and N-(3,4-dimethoxybenzylidene)-4-ethoxyaniline (2) were synthesized and characterized by elemental analyses (CHN) and FT-IR spectroscopic techniques. Crystal structures of 1 and 2 were obtained by single-crystal X-ray diffraction. Compound 1 crystallizes in the monoclinic, space group P21 with two independent molecules (A and B), with unit cell parameters: a = 14.8198(4), b = 7.1656(2), c = 13.2982(4)? , ß = 103.289(2)°, V = 1374.36(7)? 3 and Z = 4 and compound 2 crystallizes in the monoclinic space group P21/n with unit cell parameters: a = 16.5638(6), b = 7.3546(2), c = 12.7449(4)? , ß = 106.021(4)°, V = 1492.28(9)? 3 and Z = 4.