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1.
A. Dziewulska-Kułaczkowska L. Mazur W. Ferenc 《Journal of Thermal Analysis and Calorimetry》2009,96(1):255-260
The zinc(II) complex with nicotinamide (ncam) was prepared and investigated by single-crystal X-ray diffraction, infrared
spectrum (FTIR), conductivity and thermal analysis techniques. The formula of complex is [Zn(ncam)2(H2O)4](NO3)2·2H2O. The nicotinamide molecule has three following donor sites: pyridine ring nitrogen, aminonitrogen and carbonyl group oxygen.
In this monomeric complex, the Zn(II) ion is six-coordinated by two pyridine ring N atoms and four water O atoms in a slightly
distorted octahedral arrangement. In the crystal structure, intermolecular O-H…O and N-H…O hydrogen bonds link the molecules
to form a supramolecular structure. The complex is stable up to 323 and above 360 K it dehydrates in one step losing six water
molecules. The dehydration proceeds in the range of 360–438 K, and its enthalpy value is equal to 62.6±1.5 kJ mol−1. 相似文献
2.
The new zinc ternary complexes [Zn(cyclen)NO3]ClO4 (I), [Zn2(cyclen)2(m-nic)](ClO4)3 (II), [Zn2(cyclen)2(m-pic)](ClO4)3 (III) (cyclen=1,4,7,10-tetraazacyclododecane; nic=nicotinic acid; pic=picolinic acid) were synthesized and their spectral and thermal properties were investigated. The compounds were characterized
by elemental analysis, IR spectroscopy and TG/DTG, DTA methods. Moreover, the way of coordination of pyridinecarboxylate anions
was proposed on the basis of the spectral data and consequently proved with results of X-ray structure analysis.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
3.
Katarína Győryová J. Chomič Erika Szunyogová Lenka Piknová V. Zeleňák Zuzana Vargová 《Journal of Thermal Analysis and Calorimetry》2006,84(3):727-732
Three
new complex compounds of general formula Zn{4-ClC6H3-2-(OH)COO}2⋅L2⋅nH2O
(where L=thiourea (tu), nicotinamide (nam),
caffeine (caf), n=2,3), were prepared and
characterized by chemical analysis, IR spectroscopy and their thermal properties
were studied by TG/DTG, DTA methods. It was found that the thermal decomposition
of hydrated compounds starts with the release of water molecules. During the
thermal decomposition of anhydrous compounds the release of organic ligands
take place followed by the decomposition of salicylate anion. Zinc oxide was
found as the final product of the thermal decomposition performed up to 650°C.
RTG powder diffraction method, IR spectra and chemical analysis were used
for the determination of products of the thermal decomposition. 相似文献
4.
E. Jóna A. Mašlejová M. Kubranová P. Šimon 《Journal of Thermal Analysis and Calorimetry》1996,46(1):129-138
The stoichiometry of thermal decomposition and the relationship between the thermal parameters (quasi-equilibrium decomposition temperaturesT
D and decomposition entalpies H
D) of NiL4(NCS)2 complexes (L=imidazole derivatives) were studied. It was found that changes in the experimental conditions strongly influence the decomposition stoichiometry. TheT
D and H
D can be ordered in the following sequence (according toL): imidazole<2-Me imidazole<2-Et imidazole相似文献
5.
Erika Szunyogová Dagmar Mudroňová Katarína Györyová Radomíra Nemcová Jana Kovářová Lenka Piknová-Findoráková 《Journal of Thermal Analysis and Calorimetry》2007,88(2):355-361
Spectroscopic (IR), thermoanalytical (TG/DTG, DTA) and biological methods
were applied to investigate physicochemical and biological properties of seven
zinc(II) complex compounds of the following formula Zn(HCOO)2·2H2O
(I), Zn(HCOO)2·tph (II), Zn(CH3COO)2·2H2O (III), Zn(CH3COO)2·tph
(IV), Zn(CH3COO)2·2phen
(V), Zn(CH3CH2COO)2·2H2O
(VI), Zn(CH3CH2CH2COO)2·2H2O (VII), where tph=theophylline, phen=phenazone. The formation of various
intermediates during thermal decomposition suggests the dependence on the
length of aliphatic carboxylic chain and type of N-donor ligand (tph, phen).
The final product of the thermal decomposition was ZnO. The antimicrobial
activity of these complexes were tested against G+
and G– bacteria. Strong inhibitive effect
was observed towards E. coli, salmonellae
and Staph. aureus. 相似文献
6.
Chomič J. Györyová K. Szunyogová E. Kováéová J. 《Journal of Thermal Analysis and Calorimetry》2004,76(1):33-41
Five new complex compounds of general formula Zn(Hsal)2·L2·nH2O (where Hsal=OHC6H4COO-, L=thiourea (tu), nicotinamide (nam), caffeine (caf), theobromine (tbr), n=2-4), were prepared and characterized by chemical analysis, IR spectroscopy and studied by methods of thermal analysis (TG/DTG,
DTA). It was found that the thermal decomposition of hydrated compounds starts with the release of water molecules. During
the thermal decomposition of anhydrous compounds the release of organic ligands take place followed by the decomposition of
salicylate anion. Zinc oxide was found as the final product of the thermal decomposition heated up to 800°C. RTG powder diffraction
method, IR spectra and chemical analysis were used for the determination of products of the thermal decomposition.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
7.
J. Cernák J. Skorsepa J. Chomic I. Potocnák J. Hoppan 《Journal of Thermal Analysis and Calorimetry》1994,41(1):91-98
Two new tetracyano complexes of the composition MnenNi(CN)4 and MnenCd(CN)4 were prepared and identified. Their struture and properties were investigated by IR and UV-VIS spectroscopy, X-ray powder diffraction and by measuring magnetic moments. The results were confronted with the structure and properties of the compounds CdenNi(CN)4 and CdenCd(CN)4. The results of this study show a considerable similarity between these groups of compounds. The thermal behaviour of all the examined compounds was investigated derivatographically. The following order of thermal stability of the investigated complexes was observed: Cd?Cd(215°C)相似文献
8.
Icbudak H. Heren Z. Kose D. Ali Necefoglu H. 《Journal of Thermal Analysis and Calorimetry》2004,76(3):837-851
The mixed-ligand p-hydroxybenzoate complexes of Ni(II), Cu(II) and Zn(II) with nicotinamide and N,N-diethylnicotinamide were synthesized and
characterized by elemental analysis, magnetic susceptibility measurements and mass spectrometry. The thermal behavior of the
complexes was studied by simultaneous TG, DTG and DTA methods in static air atmosphere. The infrared spectral characteristics
of the complexes are also discussed. The complexes contain two water molecules, two p-hydroxybenzoato (p-hba) and two nicotinamide (na) (or diethylnicotinamide (dena)) ligands per formula unit. In these complexes,
all ligands are coordinated to the metal ion as monodendate ligands. In Zn(II)-na and Cu(II)-dena complexes, thep-hydroxybenzoate behaves as bidentate chelating ligand through carboxylic oxygen atoms. The decomposition pathways and the
stability of the complexes are interpreted in the terms of the structural data. The final decomposition products were found
to be the respective metal oxides.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
9.
A. A. M. Aly A. H. Osman N. Abo El-Maali G. A. A. Al-Hazmi 《Journal of Thermal Analysis and Calorimetry》2004,75(1):159-168
Zn(II) complexes of some cephalosporin antibiotics namely cephalexin, cephapirin, cefamandole, cefuroxime, cefotaxime and ceftazidime were synthesised and characterized. The stoichiometrics and the mode of bonding of the complexes were deduced from their elemental analysis, IR and electronic spectroscopies. Thermal stabilities and the photochemical behaviour of the complexes were studied. The Zn(II) complex of cephalexin exhibited a high light sensitivity. The remaining Zn(II) complexes behaved similarly to their free antibiotics, upon irradiation.This revised version was published online in November 2005 with corrections to the Cover Date. 相似文献
10.
The hydrazinium(1+) metal acetates and malonate dihydrates of the molecular formula [(N2H5)2M(CH3COO)4] and (N2H5)2[M(OOCCH2COO)2(H2O)2] respectively, whereM=Co, Ni or Zn, have been prepared and characterized by chemical analyses, conductance, magnetic, spectral, thermal and X-ray powder diffraction studies. The magnetic moments and electronic spectra indicate that these complexes are of high-spin octahedral variety. The infrared spectra show that the hydrazinium ions are coordinated in the case of acetate complexes, whereas in the malonate complexes the hydrazinium ions are out side the coordination sphere. These complexes undergo exothermic decomposition in the temperature range 150–450°C to give the respective metal oxide as the final residue. The X-ray powder diffraction patterns of the malonate complexes indicate isomorphism among them. 相似文献
11.
Hydrazinium metal glycinates [(N2H5
2M(NH2CH2COO)4] and bis(hydrazine)metal glycinates, [M(NH2CH2COO)2(N2H4)2], whereM=Co, Ni or Zn have been prepared and characterized by chemical analyses, magnetic moments and vibrational and electronic spectra. The thermal behaviour of these compounds has been studied by thermogravimetry and differential thermal analyses. These complexes decompose with high exothermicity giving metal powder as the final residue. The X-ray powder data of each set of complexes show isomorphism among themselves. 相似文献
12.
Copper(II) and zinc(II) complexes of Schiff bases obtained by condensation of amoxicillin and cephalexin with salicylaldehyde/pyridoxal were prepared and characterized by microanalytical, thermogravimetric, magnetic and spectroscopic data. All the complexes were found to be six‐coordinate and containing two water molecules. The electron paramagnetic resonance spectral lines exhibited rhombic distortion from axial symmetry, with g|| > g? > ge, in the copper(II) complexes. The geometry of the zinc(II) complexes appears to be octahedral. All the compounds under investigation showed antibacterial activity. The antibacterial activity showed the following trend: copper(II) complexes > zinc(II) complexes > Schiff base ligands > parent drugs. The copper(II) complexes with the Schiff bases derived from cephalexin showed substantially enhanced activity against Pseudomonas aeruginosa compared with the parent drug. All the copper complexes were also found to be active against kaolin paw oedema, whereas the parent drugs were inactive. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
13.
New zinc acetate based complex compounds (of general formula Zn(CH3COO)2·1?2L·nH2O) containing one or two molecules of urea, thiourea, coffeine and phenazone were prepared namely: Zn(CH3COO)2·2.5H2O, Zn(CH3COO)2·2u·0.5H2O, Zn(CH3COO)2·tu·0.5H2O, Zn(CH3COO)2·2tu, Zn(CH3COO)2·cof·2.5H2O, Zn(CH3COO)2·2cof·3.5H2O, Zn(CH3COO)2·2phen·1.5H2O. The compounds were characterized by IR spectroscopy, chemical analysis and thermal analysis. Thermal analysis showed that no changes in crystallographic modifications of the compounds take place during (heating in nitrogen before) the thermal decompositions. The temperature interval of the stability of the prepared compounds were determined. It was found that the thermal decomposition of hydrated compounds starts by the release of water molecules. During the thermal decomposition of anhydrous compounds in nitrogen the release of organic ligands take place followed by the decomposition of the acetate anion. Zinc oxide and metallic zinc were found as final products of the thermal decomposition of the zinc acetate based complex compounds studied. Carbon dioxide and acetone were detected in the gaseous products of the decomposition of the compounds if ZnO is formed. Carbon monoxide and acetaldehyde were detected in the gaseous products of the decomposition, if metallic Zn is formed. It is supposed that ZnO and Zn resulting from Zn acetate complex compounds here studied, possess different degree of structural disorder. Annealing takes place by further heating above 600°C. 相似文献
14.
Erika Szunyogová Katarína Györyová Daniela Hudecová Lenka Piknová J. Chomič Zuzanna Vargová V. Zeleňák 《Journal of Thermal Analysis and Calorimetry》2007,88(1):219-223
The thermal decomposition of the complexes Zn(form)2⋅2phen
(I), Zn(ac)2⋅2phen
(II), Zn(prop)2⋅2phen
(III), Zn(but)2⋅2phen
(IV), where phen=phenazone, form=formiate,
ac=acetate, prop=propionate, but=butyrate has been studied in air by TG/DTG
and DTA methods. The possible mechanism of the thermal decomposition was proposed.
The final product of thermal decomposition was ZnO. IR data show unidentate
coordination of carboxylate group to Zn(II) ion. The complexes were tested
against various strains of microorganisms and their efficiency decrease in
the sequence yeasts >bacteria>filamentous fungi. 相似文献
15.
《Mendeleev Communications》2022,32(4):471-473
Crystallization of copper and zinc complexes with imino terpene derivatives of ethylenediamine causes unexpected chemical transformation of the ligand. Copper(II) chloride catalyzes the hydrolysis of the imine and also acts as a halogenating agent. Crystallization of the zinc complex in acetone is accompanied by the condensation of the ketone with the primary amino group of the ligand. 相似文献
16.
The thermal stabilities of 5-chloro-2-methoxybenzoates of Mn(II), Co(II), Ni(II), Cu(II) and Zn(II) were studied in air and
nitrogen atmospheres. The complexes were obtained as mono-, di-, tetra-and pentahydrates with a metal to ligand ratio of 1:2
and with colours typical for M2+ ions (Mn-slightly pink, Co-pink, Ni-green, Cu-blue and Zn-white) and as polycrystalline compounds. When heated they dehydrate
to form anhydrous salts which nextare decomposed to the oxides of the respective metals in air while in nitrogen to the mixtures
of metal oxides and oxychlorides and carbon. The most thermally stable in air, nitrogen and argon atmospheres is 5-chloro-2-methoxybenzoate
of Cu(II) while the least thermally stable is that of Co(II).
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
17.
The thermal properties of cyanatocopper complexes with pyridine, bipyridine and phenanthroline are described in this paper. It was found that the thermal stabilities of the complexes were found to increase in the order pybipy2(NCS)2 (L=pyridine and its methyl derivates) which are composed of the liberation of ligandsL and redox reactions of thiocyanate ligands with the central Cu(II) atom [1, 2]. The decomposition temperature of thiocyanate ligands depends on the properties of the ligandsL present in the coordination sphere. An analogous course of thermal decomposition was also observed for [Cu(bipy)2(NCX)](NCX) (X=S or Se) [3]. For the phenanthroline complexes [Cu(phen)2(NCX)2] (X=S or Se) the thermal stability was found to increase significantly (by about 140C) and the decomposition stoichiometry was also changed [3].The present paper contains the results of thermoanalytical studies on bipyridine and phenanthroline cyanatocopper complexes, and a comparison of the thermal properties of pyridine cyanato and isothiocyanatocopper complexes. 相似文献
18.
Complexes of the general formulae Mn(2-bpy)2(CCl3COO)2, Co(2-bpy)2(CCl3COO)2·H2O and Ni(2-bpy)2(CCl3COO)2·2H2O (where: 2-bpy=2,2'-bipyridine) have been prepared and characterized by VIS and IR spectroscopy, conductivity and magnetic measurements.
The thermal properties of complexes in the solid state were studied under non-isothermal conditions in air atmosphere. During
heating the complexes decompose via different intermediate products to the oxides Mn3O4, CoO and NiO. A coupled TG-MS system was used to detection the principal volatile products of thermal decomposition and fragmentation
processes of obtained compounds. The principal volatile products of thermal decomposition of complexes are: H2O+, CO2
+, Cl2
+ and other.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
19.
D. Czakis-Sulikowska J. Radwańnska-Doczekalska M. Markiewicz M. Pietrzak 《Journal of Thermal Analysis and Calorimetry》2008,93(3):789-794
New mixed ligand complexes of the following stoichiometric formulae: M(2-bpy)2(RCOO)2·nH2O, M(4-bpy)(RCOO)2·H2O and M(2,4’-bpy)2(RCOO)2·H2O (where M(II)=Zn, Cd; 2-bpy=2,2’-bipyridine, 4-bpy=4,4′-bipyridine, 2,4′-bpy=2,4′-bipyridine; R=C2H5; n=2 or 4) were prepared in pure solid-state. These complexes were characterized by chemical and elemental analysis, IR and
conductivity studies.
Thermal behaviour of compounds was studied by means of DTA, DTG, TG techniques under static conditions in air. The final products
of pyrolysis of Cd(II) and Zn(II) compounds were metal oxides MO. A coupled TG/MS system was used to analyse of principal
volatile products of thermal decomposition or fragmentation of Zn(4-bpy)(RCOO)2·H2O under dynamic air and argon atmosphere.
The principal species correspond to: C+, CH+, CH3
+, C2H2
+, HCN+, C2H5
+ or CHO+, CH2O+ or NO+, CO2
+, 13C16O2
+ and 12C16O18O+ and others; additionally CO+ in argon atmosphere. 相似文献
20.
Nataliya Sh. Lebedeva Elena A. Malkova Elena V. Parfenyuk Anatoliy I. Vyugin 《Journal of inclusion phenomena and macrocyclic chemistry》2007,59(1-2):71-80
Spectral and thermochemical studies of complexes of zinc(II)tetra-tertbutylphthalocyanine (Zn(t-Bu)4Pc) with some amines have been carried out. Spectral effects of the complex formation of the metallophthalocyanine with amines
have been established. It has been found that an ability of Zn(t-Bu)4Pc to coordinate amines depends on both their nature and conditions of preparation. Similarity of the crystal structures of
biligand and monoligand of Zn(t-Bu)4Pc complexes to individual β- and α-polymorphs of Zn(t-Bu)4Pc, respectively is proved by IR spectroscopy and X-ray diffraction method. 相似文献