The crystal structures ofbis-{(2-benzotrifluoride)-[(2-oxo-3H-naphth-3-ylidene)-methyl]-aminato} Copper(II) andbis-{(3-benzotrifluoride)-[(2-oxo-3H-naphth-3-ylidene)-methyl]-aminato} Copper(II)

Summary TheSchiff base ligands 3-[(2-benzotrifluoride)-2-hydroxy-3H-naphth-3-ylidene)-methyl] aldamine (1) and 3-[(3-benzotrifluoride)-2-hydroxy-3H-naphth-3-ylidene)-methyl] aldamine (2) and their corresponding Cu(II) complexes (I, II) were synthesized. The crystal structures ofbis-{(2-benzotrifluoride)-[(2-oxo-3H-naphth-3-ylidene)]-methyl]-aminato} Copper(II) (I) andbis-{(3-benzotrifluoride)-[(2-oxo-3H-naphth-3-ylidene)-methyl]-aminato} Copper(II) (II) were determined. CompoundI crystallizes in the triclinic crystal system (a=12.561(3),b=16.211(4),c=8.007(2) Å, =96.29(2), =101.42(2), =97.10(2)°, space group ,Z=2); compoundII crystallizes in the monoclinic crystal system (a=5.064(2),b=19.172(4),c=15.111(3) Å, =95.05(2)°, space group P2₁/c,Z=2). The X-ray diffraction study shows that the geometry around the metal atom is square planar for both copper complexes.

---

Kristallstruktur vonbis-{(2-Benzotrifluorid)-[(2-oxo-3H-naphth-3-yliden)-methyl]-aminato}-Kupfer(II) undbis-{(3-Benzotrifluorid)-[(2-oxo-3H-naphth-3-yliden)-methyl]-aminato}-Kupfer(II)

Zusammenfassung DieSchiffschen Basen 3-[(2-Benzotrifluorid)-2-hydroxy-3H-naphth-3-yliden)-methyl]-aldamin (1) und 3-[(3-Benzotrifluorid)-2-hydroxy-3H-naphth-3-yliden)-methyl]-aldamin (2) sowie ihre entsprechenden Cu(II)-Komplexe (I,II) wurden synthetisiert und ihre Struktur im Kristall bestimmt. VerbindungI kristallisiert triklin (a=15.561(3),b=16.211(4),c=8.007(2) Å, =96.29(2), =101.42(2), =97.10(2)°, Raumgruppe ,Z=2); VerbindungII kristallisiert monoklin (a=5.064(2),b=19.172(4),c=15.111(3) Å, =95.05(2)°, Raumgruppe P2₁/c,Z=2). Aus der Röntgenstrukturanalyse ergibt sich eine quadratisch planare Geometrie der Komplexe.

     

Spectrophotometric study of the reaction of Co(II) and Ni(II) with nitroso-R-salt and α-nitroso-β-naphthol

The complexes of Co(II) and Ni(II) with nitroso-R-salt are studied by conductometric titration and spectrophotometric methods in buffer solutions of differentpH. The study proved the possible formation of (11), (12) and (13) complexes for Co(II) while Ni(II) forms (11) and (12) complexes (metal:ligand) only. The factors affecting complex formation are established and the formation constants of the complexes are evaluated. The ir spectra of the solid complexes with -nitroso--naphthol revealed that the ligand exhibits the nitrosophenol structure and that the reaction takes place through proton displacement from the OH-group.

---

Spektrophotometrische Studie zur Reaktion von Co(II) und Ni(II) mit Nitroso-R-Salz und -Nitroso--naphthol

Zusammenfassung Es wurden die Komplexe von Co(II) und Ni(II) mit Nitroso-R-Salz mittels konduktometrischer und spektrophotometrischer Methoden in Puffer-Lösungen mit verschiedenempH untersucht. Für Co(II) wurden (11)-, (12)- und (13)-Komplexe gefunden, während für Ni(II) lediglich (11)- und (12)-Komplexe (Metall:Ligand) festgestellt werden konnten. Die Faktoren, die die Komplexierung bestimmen, werden diskutiert und die Komplexbildungskonstanten wurden bestimmt. Die IR-Spektren der Komplexe mit -Nitroso--naphthol zeigen, daß der Ligand in der Nitrosophenol-Form vorliegt und daß die Reaktion über eine Protonenverschiebung von der OH-Gruppe verläuft.

     

Photooxidation of bis(ethylxanthato)nickel(II) containing aromatic nitrogen heterocyclic ligands in chloroform

The photochemistry of the complexes [Ni(Etxn)₂(N-N)] [Etxn=ethylxanthate,N-N=2,2-bipyridine(bpy), 4,4-dimethyl-2,2-bipyridine (4,4-Me-bpy), 1,10-phenanthroline (phen) or 2,2-bipyrimidine (bpym)] has been investigated. These complexes were not light sensitive in most solvents such as acetonitrile. Upon irradiation of chloroform solutions of these complexes, a photoredox reaction occurred giving the parent Ni(Etxan)₂. It is suggested that the reactive excited state is of the charge-transfer-to-solvent (CTTS) type. The energy of this state depends on the redox potentials of the solvent. When CHCl₃ as solvent was replaced by the stronger oxidant CCl₄, the photoactive wavelength region was shifted to the red. It was blue shifted when the weaker oxidant CH₂Cl₂ was used. From quantum yield measurements it is concluded that the photostability of the studied complexes decreases in the following order:bpym>phen>bpy>4,4-Me-bpy.

---

Photooxidation von Bis(ethylxanthato)nickel(II) mit aromatischen Stickstoffheterocyclen enthaltenden Liganden in Chloroform

Zusammenfassung Es wurde die Photochemie der Komplexe [Ni(Etxn)₂(N-N) [Etxn=Ethylxanthat,N-N=2,2-Bipyridin (bpy), 4,4-Dimethyl-2,2-bipyridin (4,4-Me-bpy), 1,10-Phenanthrolin (phen) oder 2,2-bipyrimidin (bpym)] untersucht. Diese Komplexe waren in den meisten Lösungsmitteln wie etwa Acetonitril nicht lichtsensitiv. Bei Bestrahlung von Chloroformlösungen der Komplexe trat jedoch eine Photoreaktion auf, die zum Stammkomplex Ni(Etxn)₂ führte. Es wird vorgeschlagen, für den reaktiven angeregten Zustand einen Charge-Transfer-zu-Lösungsmittel (CTTS)-Typ anzunehmen. Die Energie dieses Zustands hängt vom Redoxpotential des Lösungsmittels ab. Bei Ersatz von CHCl₃ als Lösungsmittel durch das stärkere Oxidans CCl₄ wurde die photoaktive Wellenlänge nach Rot verschoben. Eine Blauverschiebung ergab sich hingegen, wenn das schwächere Oxidans CH₂Cl₂ verwendet wurde. Aus Messungen der Quantenausbeuten ergab sich die folgende Ordnung nach abnehmender Photostabilität der untersuchten Komplexe:bpym>phen>bpy>4,4-Me-bpy.

     

Studies of the reaction mechanism between copper(I) sulphide and excess copper(II) sulphate

The reaction between copper(I) sulphide and excess copper(II) sulphate in the temperature range 600–750 K was investigated by methods of thermal analysis as well as by measuring the phase composition as a function of the fractional conversions. The reaction proceeds in four stages. The transient products are Cu₂S, a Cu₂SO₂ phase and CU₂SO₄, and the final product is CU₂O with the non-defect structure. The initial composition of the substrate mixture strongly influence the reaction kinetics.

---

Zusammenfassung Die Reaktion zwischen Kupfer(I)-sulfid und überschüssigem Kupfer(II)-sulfat im Temperaturbereich von 600–750 K wurde mittels thermoanalytischer Methoden und durch Ermittlung der Phasenzusammensetzung in AbhÄngigkeit von der Konversion untersucht. Die Reaktion verlÄuft in vier Schritten. Als Zwischenprodukte treten CU₂S, eine Cu₂SO₂-Phase und Cu₃SO₄ auf, Endprodukt ist ein Cu₂O mit ungestörter Struktur. Die Reaktionskinetik wird stark von der Ausgangszusammensetzung des Substratgemisches beeinflu\t.

---

600–750 K , . . Cu₂S, Cu₂SO₂ + Cu₂SO₄ — Cu₂O . .

     

A calorimetric study ofN,N-dimethylformamide complexes of copper(II) in acetonitrile

Complex formation of copper(II) with N,N-dimethylformamide(DMF) has been investigated calorimetrically in acetonitrile at 25°C. Calorimetric titration curves obtained are explained in terms of formation of [Cu(dmf) _n ]²⁺ (n=1–4, 6) and their formation constants, enthalpies and entropies were determined. Formation of [Cu(dmf)₅]²⁺ is uncertain. The stepwise enthalpies S ₃ ⁰ and entropies S _n ⁰ at each consecutive step are all negative except for S ₃ ⁰ . The overall enthalpies of formation of [Cu(dmf)₆]²⁺ is –(77.8±5.4) kJ-mol^–1, which is compared with the enthalpy of transfer of copper(II) ion, H _t ^o =–79.7 kJ-mol^–1, from acetonitrile to DMF.     

Crystalline host-guest complexes involving carboxylic acid hosts and a dimethyl sulphoxide guest. X-ray crystal structures of two inclusion species

The host compounds 2,2-binaphthyl-3,3-dicarboxylic acid (1) and 1,13–1-terphenyl-2,4,4-tricarboxylic acid (2) have been synthesized, and crystal structures of their inclusion compounds with DMSO {1a [1·DMSO(11)];2a [2·DMSO (12)]} have been determined from single crystal X-ray diffraction data. The crystals show monoclinic symmetry withZ=4 (P2₁/n for1a andP2₁/c for2a), with the unit cell dimensionsa=11.567(1),b=10.206(1),c=17.579(1) Å,=100.50(1)° for1a, anda=14.910(1),b=6.732(1),c=26.084(1) Å,=100.41(1)° for2a. The structural models were refined toR=0.032 with 3127 reflections for1a, andR=0.035 with 3175 observations for2a, collected atT=173(1) K. Both structures comprise a characteristic molecular recognition pattern for DMSO via strong (CO)O–HO(=S) hydrogen bonds and possible C–HO contacts, the latter ones from the guest methyl groups to the carbonyl oxygen of the host carboxyl groups. In the crystals H-bonded endless chains of alternating host and guest molecules are formed, which are held together by ordinary van der Waals' forces. Additionally, host2 binds a second DMSO molecule by a single (CO)O–HO(=S) bond.Supplementary Data relating to this article have been deposited with the British Library at Boston Spa, Wetherby, West Yorkshire, U.K., as Supplementary Publication No. SUP 82186 (9 pages)     

Preparation and characterization of Mg(II)-, Ca(II) and Cd(II) complexes of 1,2-ethanediol and water

Mixed ligand complexes of different compositions were prepared with water, sulfate ion and 1,2-ethanediol as ligand. IR spectra and the thermoanalytical curves of the complexes were recorded. Oxygen atoms bound by one or two coordinate bonds to the metal ion, or by hydrogen-bonds in the crystal, were observed. As for the water molecule, 1,2-ethanediol molecules of crystal and monohydrate type were found, depending on the type of binding of the oxygen atoms.This revised version was published online in November 2005 with corrections to the Cover Date.     

New Molybdenum(V) Complexes Prepared by the Oxidation of Dinuclear Quadruply-Bonded Molybdenum(II) Monothiocarboxylates

Oxidation of molybdenum(II) thiopivalate and thiobenzoate in the presence of -picoline or pyridine results in the formation of dinuclear molybdenum(V) complexes of the general formulae [Mo₂O₂(-O)₂(-SO₄)L₄] with L = -picoline or pyridine and [Mo₂O₂(-O)(-S)(-SO₄)L₄] with L = -picoline. As determined by X-ray structure analysis, two complexes with -picoline differ in their bridging cores: In one complex, two Mo atoms are doubly bridged through two oxygen atoms; in the other, one Mo atom is doubly bridged through oxygen and sulfur atoms. However, they both crystallize together. The product is solvated with -picoline and water molecules. Molybdenum atoms exhibit distorted octahedral coordinations. The same complexes were prepared also through direct reactions of [Mo₂O₃(O₂CCH₃)₄] with thiopivalic and thiobenzoic acid in the presence of -picoline or pyridine. The appearance of the oxo-oxygens and sulfido-sulfur as well as sulfato ligand is explained by the molybdenum-catalyzed oxidation of thiocarboxylates.     

The synthesis and crystal structure of a cubane-like tungsten copper sulphur cluster, [W4CuS4 2P(OEt)2 3(I)(μ2-PhCO2)(MeCN)]

Summary The title compound [W₃C₃S₄{S₂P(OEt)₂}₃(I)(₂ ^–PhCO₂)(MeCN)] crystallized in triclinic system with space group P1 and cell dimensiona=11.645(6),b=18.565(2),c=11.292(7)Å, =96.15(3)°, =113.65(3)°, =93.77(3)°, V=2207.6ų, Z=2, Mr=1588.09, D_c=2.39 g cm^–3. MoK radiation, =0.71073 Å, =97.3 cm^–1, F(000)=1488, R=0.042 for 5588 observed unique reflections I3(I). There are some distortions in the cubane-like W₃CuS₄ core, with three W-W bonds and three weak W-Cu bonds. Two W atoms are coordinated by PhCO₂ bridge ligand, the other W atom is coordinated to the N atom of MeCN.     

Synthesis and X-Ray Crystal Structure Study of ]2-Methyl-4-(2-methylbenzoyl)-phenoxy] Acetic Acid Hydrazide

Benzophenone analog 3 has been synthesized and characterized by the X-ray diffraction (XRD) method. The compound crystallizes in a monoclinic space group P2₁/c with cell parameters a = 7.701(8) Å, b = 7.151(5) Å, c= 28.323(3) Å, = 104.639(4)°, Z = 4. The structure exhibits intra- and intermolecular hydrogen bonding of the type N–HO, C–HO, and N–HN. The molecules are interlinked through hydrogen bonds forming an infinite chain. This polymeric-like structure may play an important role in biological activity.     

Monomeric [Ni(2,2"-Bipy){(i-C4H9)2PS2}2] and [Ni(Pz)2{(i-C4H9)2PS2}2] and Polymeric [Ni(Pz){(i-C4H9)2PS2}2]nComplexes (Pz = Pyrazine): Synthesis,Structures, and Properties

Diamagnetic [Ni(i-Bu₂PS₂)₂] compound (I) in ethanol reacts with 2,2"-bipyridine or pyrazine to give the paramagnetic complexes [Ni(2,2"-Bipy)(i-Bu₂PS₂)₂] (II), [Ni(Pz)₂(i-Bu₂PS₂)₂] (III), and [Ni(Pz)(i-Bu₂PS₂)₂] _n (IV) (_eff= 2.91–3.12 _B). Single crystals of IIwere grown for X-ray diffraction study. The crystals are monoclinic, a= 14.669(3) Å, b= 19.693(4) Å, c= 12.155(2) Å, = 107.51(3)°, V= 3348(1) ų, Z= 4; _calcd= 1.257 g/cm³, space group P2₁/c. The structure is built from monomeric molecules. The coordination polyhedron of the Ni atom is a distorted octahedron formed by four S atoms of two bidentate chelating i-Bu₂PS^– ₂ligands and by two N atoms of bidentate cyclic 2,2"-Bipy. Preliminary data for complexes IIIand IVindicate that they also contain an octahedral NiN₂S₄fragment. The structures of complexes I(square planar) and ofII–IV(octahedral) were confirmed by data from electron spectroscopy. Electronic absorption spectra were used to determine the rankings of the i-Bu₂PS^– ₂ions and Pz on a spectrochemical scale.     

Comparative EPR study of copper(II) complexes with threonine derivatives

Summary In order to get better insight into the structural reasons for different properties of copper(II) complexes withL-threonine,L-allo-threonine,L-N,N-dimethyl-threonine, andL-N,N-dimethyl-allo-threonine, their EPR spectra were studied as a function ofpH and temperature. AtpD9.4, in all complexes a change in the copper(II) coordination sphere from the glycine to the hydroxy type was observed. Inbis(L-threoninato)copper(II), the hydroxy type formed atpD9.4 was found to be stablized by increasing the temperature of the solution from 280 to 320 K. In all other copper(II) complexes, the conformational change is accompanied by the disruption of the Cu-N bond of one chelate ring.

---

Vergleichende EPR-Untersuchungen von Kupfer(II)-Threonin-Komplexen

Zuzammenfassung Um einen besseren Einblick in die Beziehungen zwischen Struktur und Eigenschaften von Kupfer(II)-Komplexen mitL-Threonin,L-allo-Threonin,L-N,N-Dimethyl-Threonin undL-N,N-Dimethyl-allo-Threonin zu gewinnen, wurden ihre EPR-Spektren in Abhängigkeit vompH-Wert und von der Temperatur untersucht. Bei einempH-Wert von 9.4 (in deuterierter Lösung) wurde eine Veränderung in der Kupfer (II)-Koordinationssphäre festgestellt, die von einer Glycin-ähnlichen Konformation in eine vermutlich Hydroxy-ähnliche Konformation übergeht. Derbis(L-Threoninato)-Kupfer (II)-Hydroxy-Komplex wird durch eine Temperaturerhöhung von 280 auf 320K stabilisiert. Die Veränderung der Koordination vom Glycin-Typ wird von einem Bruch der Cu-N-Bindung eines Chelatrings begleitet.

     

Kinetics of the oxidation of oxalic acid by cerium(IV) sulfate in dilute sulfuric acid

The kinetics of the oxidation of oxalic acid by cerium(IV) in sulfuric acid medium has been studied voltammetrically. The specific reaction rate is 132±4.0 M^–1s^–1 at 25.0 °C. The energy of activation is 62.6±3.0 kJ mol^–1. The entropy of activation is –2.7 J mol^–1K^–1. The specific reaction rate is influenced by complexation and also by ionic strength (). The most likely mechanism has been suggested.

---

(IV) . 132±4,0 M^–1c^–1 25,0 °C. 62,6±3,0 ·M^–1. –2,7 ·K^–1M^–1. , (). .

     

Thermogravimetric investigation of some mononuclear and binuclear complexes of copper(II) acetate with pyridine derivatives

Binuclear complexes of the type Cu₂(CH₃CO₂)₄L₂ (L=pyridine, 2-chloropyridine, 3-chloropyridine, 2,4-dimethylpyridine, 3,4-dimethylpyridine, isoquinoline) and mononuclear complexes of the type Cu(CH₃CO₂)₂Py₃, Cu(CH₃CO₂)₂Py₃H₂O, Cu(CH₃CO₂)₂(3,4-Lut)₂H₂O have been investigated by thermogravimetry. A linear correlation is shown to exist between the pK_a of the base ligand and the thermal stability of the corresponding binuclear complexes as determined from the thermal analysis data. The results show that the tendency to eliminate the base ligand from these complexes decreases with decreasing basicity of the substituted pyridine. The strong steric effect associated with -substituted pyridine ligands on the decomposition temperatures of the corresponding complexes is noted.

---

Zusammenfassung Binukleare Komplexe des Typs Cu₂(CH₃CO₂)₄L₂ (L=Pyridin, 2-Chlorpyridin, 3-Chlorpyridin, 2,4-Dimethylpyridin, 3,4-Dimethylpyridin, Isoquinolin) und mononukleare Komplexe des Typs Cu(CH₃CO₂)₂Py₃, Cu(CH₃CO₂)₂Py₃ · H₂O und Cu(CH₃CO₂)₂(3,4-Lut)₂·H₂O werden thermogravimetrisch untersucht. Aus den thermoanalytischen Daten ergibt sich eine lineare Korrelation zwischen denpK _a Wert der basischen Liganden und der thermischen Stabilität der entsprechenden binuklearen Komplexen. Die Tendenz zur Eliminierung der basischen Liganden dieser Komplexe nimmt mit abnehmender Basizität der substituierten Pyridine ab. Auf den beträchtlichen, mit dem-substituierten Pyridinliganden zusammenhängenden sterischen Effekt auf die Zersetzungstemperature der entsprechenden Komplexes wird hingewiesen.

---

Cu₂(CH₃CO₂)₄L₂ (L=, 2- 3- , 2,4- 3,4- ), Cu(CH₃COO)₂Py₃, Cu(CH₃COO),Py₃·H₂O Cu(CH₃COO)₂(3,4-)₂ · H₂O. pK _a . , . ga- .

---

---

Presented at the International Summer School of Calorimetry and Thermal Analysis, Belgirate, Italy; October 1–5, 1984.

---

The financial support of the Polish Academy of Sciences is gratefully acknowledged. We are also indebted to Dr Pielak for analysing the sintered products.     

Tl2SnS3 — ein Thiostannat mit 1 ∞ -[SnS 3 2− ]-Ketten

Black, fibre-like crystals of Tl₂SnS₃ were obtained from the melt using high-purity elements. Tl₂SnS₃ is monoclinic, space group C 2/m witha=23.03 (1),b=3.834 (1),c=7.379 (3) Å, =94.07 (5)°;Z=4. The crystal structure was determined from single crystal diffractometer intensity data and refined to a conventionalR of 0.127 for 724 observed reflections. The crystal structure is of a new type. It is characterized by infinite chains, ₁ -[SnS ₃ ^2– ], formed by cornersharing SnS₄-tetrahedra. These chains run along [010], their translation period comprises one tetrahedron (Einerketten). The average Sn — S-distance is 2.397 Å. The Tl⁺-ions separating the thiostannate-chains have different sulfur coordination. The coordination figure of Tl(1) is a bicapped trigonal prism, Tl(2) is in the center of an irregular cube. A comparison of the thiostannate-chains with other simple chains built-up by corner-sharing tetrahedra is given.

Herrn Prof. Dr.Karl Schlögl zum 60. Geburtstag gewidmet.     

The crystal and molecular structure of chlorobis(N-ethyl-1 3-imidazolidine-2-thione)copper(I)

Summary The crystal structure of the title compound has been determined from x-ray diffractometer data by the heavy-atom method and refined anisotropically by least-squares calculations. Crystals are monoclinic, space groupP 2₁/c, with unit cell dimensions:a=7.321(1),b=14.622(2),c=14.827(2) Å,=92.95(2), Z=4. The finalR index is 4.6%. The copper coordination is trigonal, involving the sulphur atoms of twoN-ethyl-1,3-imidazolidine-2-thione molecules and one chlorine atom. The structure is held together by two intramolecular N-HCl hydrogen bonds and by normal van der Waals interactions.     

Thermal decomposition of copper(II)phthalate monohydrate

The thermal dehydration and decomposition of copper(II) phthalate monohydrate was studied by isothermal and non-isothermal methods. The decomposition process consisted of three steps: two steps of dehydration and the third of decomposition. The kinetics of isothermal dehydration reactions follow (i) a unimolecular law up to the formation of copper(II) phthalate hemihydrate, and (ii) a phase boundary model giving anhydrous copper(II) phthalate, while the kinetics of isothermal decomposition reaction comply with the Erofeev-Avrami equation, [–ln(1–)]^1/n =Kt+C. The energies of activation for the formation of the decomposition products were calculated. The decomposition products were characterized by elemental analysis, photomicrographic observations, infrared and reflectance spectra and X-ray powder diffraction data.

---

Zusammenfassung Die thermische Dehydratisierung und Zersetzung von Kupfer(II)Phthalat Monohydrat wurde durch isotherme und nichtisotherme Methoden untersucht. Der Zersetzungsvorgang bestand aus drei Stufen: zwei Stufen der Dehydratisierung und die dritte der Zersetzung. Die Kinetik der isothermen Dehydratisierungsreaktionen folgt (i) einem unimolekularen Gesetz bis zur Bildung von Kupfer(II)Phthalat Hemihydrat und (ii) einem Grenzflächen modell, das wasserfreies Kupfer(II)Phthalat ergibt, während die Kinetik der isothermen Zersetzungsreaktion der Erofeev-Avrami Gleichung, [–ln(1–)]^1/n =Kt+C genügt. Die Aktivierungsenergien für die Bildung der Zersetzungsprodukte wurden berechnet. Die Zersetzungsprodukte wurden durch Elementaranalyse, mikrophotographische Beobachtungen, Infrarot- und Remissionsspektra sowie Röntgen-Pulverdiffraktionsdaten charakterisiert.

---

Résumé On a étudié, par des méthodes isothermes et non-isothermes, la déshydratation et la décomposition thermique du phtalate de cuivre(II) monohydraté. Le procèssus de décomposition consiste en trois étapes: deux étapes de déshydratation et la troisième de décomposition. La cinétique des réactions de déshydratation isotherme suit (i) une loi unimoléculaire jusqu'à la formation de phtalate de cuivre(II) hémihydraté, et (ii) un modèle de surfaces limites qui donne du phtalate de cuivre(II) anhydre, tandis que la cinétique de la réaction de décomposition isotherme satisfait l'équation d'Eroféev-Avrami: [–ln(1–)]^1/n =Kt+C. On a calculé les énergies d'activation de la formation des produits de décomposition. On a caractérisé les produits de décomposition par analyse élementaire, par des observations micrographiques, des spectres infrarouges et d'émission ainsi que par des données de diffraction sur poudre des rayons X.

---

(II). : . (II) , (II). - : [-In(1-)]^1/n=Kt+. . , , , .

---

---

One of the authors (C. M. K.) is grateful to the University of Jammu, Jammu, for the award of a Fellowship.     

Thermal Decomposition Kinetics of the Zn(II) Complex with Norfloxacin in Static Air Atmosphere

The thermal decomposition of Zn[NFA]₂5H₂O (NFA=C₁₆H₁₈FN₃O₃, norfloxacin) and its kinetics were studied under non-isothermal conditions in air by TG-DTG and DTA methods. The intermediate and residue for each decomposition were identified from the TG curve. The non-isothermal kinetic data were analyzed by means of the Achar method and the Madhusudanan-Krishnan-Ninan (MKN) method. The possible reaction mechanisms were investigated by comparing the kinetic parameters. The kinetic equation for the second stage can be expressed as d/dt=Aexp(–E/RT)(1–).This revised version was published online in November 2005 with corrections to the Cover Date.     

Thermal decomposition of bis-(DL-valinato)copper(II) and bis-(DL-methioninato)copper(II)

A kinetic study of the thermal decomposition of the complexes bis-(DL-valinato)copper(II) and bis-(DL-methioninato)copper(II) was carried out using thermogravimetry in a dynamic regime, following the theoretical model of Satava and including the equation used by Johnson and Gallagher:1/1––1=kt. Kinetic parameters were calculated and are compared with those obtained previously for the complex bis-(L-tryptophanato)copper(II). The sequence of thermal stability found is: Cu(DL-Val)₂22.

---

Zusammenfassung Die thermische Zersetzung der Komplexe Bis-(DL-valinato)kupfer(II) und Bis-(DL-methioninato)kupfer(II) wurde thermogravimetrisch im dynamischen Regime untersucht, indem von dem theoretischen Modell von atava Gebrauch gemacht und die von Johnson und Gallagher benutzte Gleichung 1/1-–1=kt einbezogen wurde. Kinetische Parameter wurden berechnet und mit den kürzlich für den Komplex Bis-(L-tryptophanato)kupfer(II) erhaltenen parametern verglichen. Die Stabilität der Komplexe nimmt in folgender Reihenfolge zu: Cu(DL-Val)₂22.

---

-(-)- -(L-) (II) , -: 1/1– –1=kt. -(L-) (II). Cu(DL-Val)₂22.

---

---

Presented at the 1985 World Conference on Thermal Analysis, Bad Hofgastein, Austria.     

Synthesis and crystal structure of a cubane-like molybdenum copper sulphur bromide cluster [MoCu3S3Br(SCH2CH2S)(PPh3)3]·MeCN

Summary [MoCu₃S₃Br(SCH₂CH₂S)(PPh₃)₃]·MeCN, MW=1382.78, space group Pl, has the triclinic cell parametersa=12.272(11),b=13.172(7),c=20.363(3)Å, =106.26(3)^o, =95.64(5)^o, =65.79(6)^o; Z=2, V=2881.4ų. Dc=1.55 g cm^–3. MoK radiation. =0.71073Å, =22.8 cm^–1. F(000)=1348. R=0.69 for 4964 observed unique reflections [I>3(I)]. There are some distortions in the cubane-like MoCu₃S₃Br core, with three form Mo–Cu bonds. The Mo atom is bound by chelating SCH₂CH₂S and three ₃-S atoms.