To improve the quality of the target product, the possibility of replacing zinc with ascorbic acid in the synthesis of maleic complexes of Cu+ and copper-containing composites based on them was investigated. The analysis of the results of potentiometric titration of a solution of 1M CuSO4, 1M maleic acid (H2M) with a neutralised solution of 1M ascorbic acid (H(2)Asc) showed that HAsc(-) anions behave exclusively as a one-electron reducing agent, and the existing conjugation of the redox systems [Cu(HM)](+)/[Cu(HM)] and HAsc/*Asc(-) contributes to a decrease in the yield of the target product, the maleate Cu+ complex. It has been found that about 50% of ascorbic acid reacts with [Cu(HM)](+) ions, and this figure is unchanged in the range of low reducing agent concentrations (up to 0,01M) and in the range of high concentrations (up to 1 M). A two-step scheme for the synthesis of the {[Cu(HM)(H2O)]xCu} composite was implemented, in which the reduction of copper ions was carried out exclusively with ascorbic acid. At the first stage, the [Cu(HM)](+) complex was reduced to [Cu(HM)]. At the second stage, the required amount of 1M CuSO4 solution was added to the suspension of [Cu(HM)] in a 1M solution of neutralised ascorbic acid to obtain the composite {[Cu(HM)(H2O)]0,5Cu}. It was found that the [Cu(HM)] complex isolated from the ascorbate solution is a highly stable form with respect to atmospheric oxygen. Microbiological studies of the effect of the obtained substances on Staphylococcus aureus and Escherichia coli strains confirmed the high bactericidal activity of the maleinate complex compared to the composite.

The study explored the process of anodic ionization of copper in an aqueous solution of maleic acid (H 2 M): we substantiated the optimal conditions for the electrochemical synthesis of Cu + maleate complexes, ensuring nearly a 100 % yield of the target product under the following parameters: potentiostatic mode, anode potential of 0.1 V (vs. silver/silver chloride electrode), concentration of (H 2 M) = 0.1 M (pH = 2), and temperature (t degrees) = 60 degrees C. By utilizing spectrophotometry, along with quantum -chemical modeling of absorption spectra for various complex structures, we determined the composition of the obtained product as [Cu + (H 2 O) 3 (HM - )]. We chose the diagnostic criterion for identifying the nature of the complex as the difference in wavelength absorption for light in the pi-bond of Cu + with the sp 2 -hybridized carbon atom of the vinyl fragment of the maleate ion (around 400 nm) and the sigma-bond of Cu + with the ionized carboxyl group (around 300 nm). For the quantitative analysis of the working solution regarding the content of maleate pi-complexes of Cu+, we suggest using the A, C -dependence measured at 360 nm.

Samples of the multicomponent high-entropy alloy CoCrFeMnNiBe were obtained by the methods of casting and melt-quenching, and their phase composition and electrochemical behavior were investigated. With the help of X-ray phase analysis, it was established that the studied alloy in the as-cast state has a multiphase structure, in which there are phases with lattices of the FCC, BCC, and BeNi(Co) intermetallics (structural type B2). Quenching from the melt leads to a significant decrease in the BCC phase content. The values of stationary potentials and areas of electrochemical stability of cast and melt-quenched CoCrFeMnNiBe alloy samples, as well as corrosion current densities, were determined. It is shown that all samples of the CoCrFeMnNiBe alloy behave inertly in corrosion tests, which allows them to be considered corrosion-resistant. The results of the work can be used in the development of modern multifunctional and corrosion-resistant materials.

The results of the study of the effect of water and oxygen on copper-containing composites [Cu(HM)(H2O)]& BULL;хCuO are presented in the paper. Composites were products of reduction of Cu2+-ions by zinc in the presence of maleic acid (H2M). The effect of these composites' suspensions on bacteria strains of Staphylococcus aureus and Staphylococcus epidermidis has been studied as well. It was found that the composites [Cu(HM)(H2O)]xCu0 contain copper maleate complexes of two modifications: mononuclear [Cu(HM)(H2O)] and binuclear [Cu(HM)(H2O)]Cu0. [Cu(HM)(H2O)] complex is the soluble form as a result of its significantly higher hydrophilicity. This complex is also the main bioactive component, which is proved by the fact that the antibacterial effect of the composites on staphylococcus strains changes synchronously with the change of their solubility in the x-interval from 0 to 1. The absence of atomic copper & pi;-complexes [Cu(H2M)(H2O)] in composites with x > 1 leads to a sharp decrease in their bactericidal activity. Last fact confirms the conclusion about the nature of the bioactive substance and indicates that bioactive metal nanodispersion does not formed in composites concentrated by copper atoms. It was shown that the optimal composition of the copper-containing composite corresponds to the formula [Cu(HM)(H2O)] 0.5Cu0. This substance has a sufficiently high level of bactericidal activity but it is highly resistant to the oxidation by atmospheric oxygen in combination with water unlike [Cu(HM(H2O)] complexes.

Quantum chemical modeling (Gaussian 09, AIM2000, Chemcraft 1.8) of the interaction of copper atoms with acidic maleate complexes Cu+ [Cu(HM)(H2O)] made it possible to identify two types of thermodynamically stable binuclear pi-complexes of the general composition [Cu-2(HM)(H2O)(2)]. Type A is characterized by a framework structure in which both Cu+ ions and Cu-0 atoms form pi-bonds with sp2-hybridized carbon atoms of the vinyl fragment of the maleate ion within separate six -membered cycles (-Cu-C-C=O-H-O-). Type B is a linear sigma-connection of a hydrated copper atom with the carboxyl oxygen of the maleate ion. The closeness of the formation energies of molecules A and B (-114.39 kJ/mol and -127.84 kJ/mol, respectively) indicates a high probability of their simultaneous formation during the synthesis of the composite {Cu(HM)Cu+}. X-ray diffraction analysis of composite samples confirmed that there is no metallic copper phase in it, but there is a phase of a new substance - products of the interaction of Cu-0 atoms with pi-complexes [Cu(HM)((HO)-O-2)]. The analysis of the obtained results of our theoretical and experimental research indicates that during the synthesis of copper -containing composites {Cu(HM)+Cu} by partial chemical reduction of maleate complexes of Cu+, a mixture of mononuclear pi-complexes [Cu(HM)((HO)-O-2)] with various binuclear pi-complexes [Cu-2(HM)((HO)-O-2)(2)] is formed.

The phase composition and corrosion-electrochemical properties of Fe5CrCuNiMnSi and Fe5CoCuNiMnSi spalt-quenched high-entropy alloy films were studied. The alloy films were fabricated by a known technique of splatquenching. A cooling rate estimated by film thickness was - 10 6 K/s. The electrochemical behavior and corrosion resistance was determined in a neutral solution of sodium chloride. Using X-ray diffraction analysis, the phase composition and crystal lattice parameters of the investigated high-entropy alloy films were determined. It was established that both Fe5CoCuNiMnSi and Fe5CrCuNiMnSi spalt-quenched high-entropy alloys are solid solutions with a face-centered cubic lattice. The values of stationary potentials and areas of electrochemical stability of alloys, as well as the density of corrosion currents, are determined. It has been shown that samples of the Fe5CrCuNiMnSi alloy behave inertly in corrosion tests. The obtained results also were compared with the characteristics of similar alloys obtained by casting

The structure and corrosion of quasicrystalline Al-Ni-Co alloys in acidic (pH = 1.0) and neutral (pH = 7.0) aqueous solutions were investigated. The methods of quantitative metallography, X-ray diffraction, scanning electron microscopy, energy dispersive spectrometry, gravimetry, and cyclic voltammetry were applied. The susceptibility of the alloys to corrosion decreased as pH value increased.

The results of quantum-chemical modeling of complex structures that can form from Cu2+ aqua complexes, chloride ions, and anions of organic acids (malonic, succinic, maleic, fumaric, formic, acetic, propionic, butanoic, and acrylic) are considered. It is shown that the series of organic acids under study forms two linear correlation dependences of pK of Cu2+ monosubstituted acidoaquacomplexes on the effective charge of the central atom. One correlation is related to anions of monobasic acids, and the other is related to anions of dibasic acids. Using the parameters of the corresponding pK, z*(Cu2+) dependence and the results of calculation of z*(Cu2+) made it possible to determine the pK value for Cu2+ acrylate complexes, equal to 1.778, information about which is not available in the literature. The degree of change in the effective charge of Cu2+ ions in the [Cu2+(L)] complexes was used to estimate the electron donation power of the ligands: anions of organic acids (-51.95 %) > Cl- (-47.75 %) > H2O (-21.45 %). However, in polyligand aquacomplexes, due to the formation of the bidentate hydrate L center dot H2O, anions of organic acids are inferior to chloride ions. With the introduction of chlorine anions into the inner coordination sphere of the Cu2+ aqua complexes monosubstituted by organic acid anions, a regular weakening of the Cu2+-L bonds is observed. The degree of decrease in Eb(Cu2+-L) depends on the nature of the organic acid. For saturated structures, Delta E-b is in the range of 2-8 kJ/mol; for unsaturated structures, it reaches 20 kJ/mol. The energy of the reaction of substitution of water molecules in Cu2+ acidoaquacomplexes by chlorine anions also changes synchronously (from -4 to -30 kJ/mol).

In this work corrosion behavior of the Al72Co18Ni10, Al65Co20Cu15, and Al72Fe15Ni13 alloys forming decagonal quasicrystalline phases was tested in the neutral NaCl solution (pH = 7) which allows a comparison of their corrosion resistance under conditions comparable to application in marine climate. The microstructure of the alloys was studied by quantitative metallographic, X-ray, scanning electron microscopic, and energy dispersive analyses. The corrosion properties were determined by gravimetric and potentiodynamic methods. The Al65Co20Cu15 and Al72Fe15Ni13 alloys have been established to corrode in the sodium chloride solution more strongly than the Al72Co18Ni10 alloy. The corrosion that proceeds under electrochemical mechanism is accompanied by the formation of passive layer on the surface that retards further dissolution in the saline solution after 3–4 days of testing. Scanning electron microscopy shows the marks of pitting corrosion. The pits appear mostly where flaws and boundaries of iron- or aluminum-rich crystalline phases are located. Their quantity and size are lesser on the surface of the Al72Co18Ni10 alloy since Co and Ni in its composition are rate determining for the corrosion processes. This alloy may be recommended as starting material for plasma-spayed coatings working in marine climate.

The structure and corrosion properties of quasicrystalline Al 65 Co 20 Cu 15 and Al 72 Co 18 Ni 10 reinforcement alloys and associated composite coatings produced by pressureless infiltration were studied. Copper-based L62 and BrOTs 10-2 alloys and aluminum-based AMg30 alloy were used as metallic matrices for the composite coatings. The structural and phase composition of the reinforcement alloys and coatings was determined by metallography, scanning electron microscopy, energy-dispersive X-ray spectrometry, and X-ray diffraction. The corrosion properties were studied in aqueous solutions of HCl, H 2 SO 4 , HNO 3 , and H 3 PO 4 acids (pH = 1.0) for 1 to 4 h at room temperature. A quasicrystalline decagonal D phase was found to coexist with crystalline Al 4 (Co, Cu) 3 and Al 3 (Cu, Co) 2 phases in the Al 65 Co 20 Cu 15 reinforcement alloy and Al 9 (Co, Ni) 2 and Al(Co, Ni) 2 phases in the Al 72 Co 18 Ni 10 alloy. Corrosion tests in acid solutions revealed that the Al 65 Co 20 Cu 15 reinforcement alloy had higher corrosion resistance in sulfuric and nitric acid solutions, while the Al 72 Co 18 Ni 10 reinforcement alloy in hydrochloric and phosphoric acid solutions. In infiltration of the Al 65 Co 20 Cu 15 and Al 72 Co 18 Ni 10 reinforcement alloys, the molten copper-based L62 and BrOTs 10-2 matrices penetrated into the reinforcement along boundaries of the quasicrystalline D phase through the preferential dissolution of crystalline phases of the reinforcement alloys. Unlike the copper-based alloys, the aluminum-based AMg30 matrix did not penetrate inside the reinforcement alloys, dissolving predominantly the crystalline phases located in the surface layers. The highest corrosion resistance in the acidic environments was shown by the composite coatings with the BrOTs 10-2 matrix. The coatings with the AMg30 matrix had the lowest corrosion resistance because of the Al 3 Mg 2 phase that emerged at interfaces between the reinforcement alloy and solidified matrix.

The corrosion properties of Al-Cu-Fe and Al-Cu-Co alloys that form quasicrystalline phases differing in crystallographic order, respectively three-dimensional icosahedral v-phase and two-dimensional decagonal D-phase, were investigated in this work. The structure of the alloys was studied by methods of quantitative metallographic, atomic absorption spectroscopic, X-ray diffraction, and scanning electron microscopic analyses. Corrosion was explored for 1-4 hours by gravimetric method in HNO3, HCl, H3PO4, and H2SO4 aqueous acidic solutions (pH = 1.0) at room temperature. After 4 testing hours, the maximal specific mass loss of the Al-Cu-Fe alloys was established to occur in the sulphuric acid and minimal mass loss - in the ortophosphoric acid. For the Al-Cu-Co alloys, maximal specific mass loss was observed in the ortophosphoric acidic solution and minimal - in the nitric acidic solution. In all investigated acidic media, the Al-Cu-Co alloys forming decagonal quasicrystals showed higher resistance to corrosion than the Al-Cu-Fe alloys forming icosahedral quasicrystals. The results of corrosion tests were explained considering the surface morphology of the samples exposed to acidic attacks studied by scanning electron microscopy. The phases containing less iron in the structure of the Al-Cu-Fe alloys or phases containing more cobalt in the structure of the Al-Cu-Co alloys are less susceptible to corrosion.

The structure of as-cast quasicrystalline Al 65 Co 20 Cu 15 , Al 72 Co 18 Ni 10 , and Al 72 Ni 23 Fe 5 alloys and their corrosion properties in acid media are investigated. We study the structure by the methods of quantitative metallography, X-ray diffraction analysis, scanning electron microscopy, and electron-probe microanalysis and investigate the corrosion resistance in aqueous solutions of HCl, H 2 SO 4 , HNO 3 and H 3 PO 4 acids (рН 1) by the gravimetric method. We reveal the formation of a quasicrystalline decagonal D -phase, which coexists with Al 4 (Co, Cu) 3 and Al 3 (Cu, Co) 2 phases in the Al 65 Co 20 Cu 15 alloy, with the Al 9 (Co 1– x Ni x ) 2 phase in the Al 72 Co 18 Ni 10 alloy, and with Al 13 (Fe,Ni) 4 , Al 3 (Ni, Fe) 2 , and Al 3 (Ni, Fe) phases in the Al 72 Ni 23 Fe 5 alloy. The Al 72 Ni 23 Fe 5 and Al 65 Co 20 Cu 15 alloys exhibit the highest corrosion resistance in solutions of nitric acid, the Al 72 Ni 23 Fe 5 and Al 72 Co 18 Ni 10 alloys are most corrosion-resistant in solutions of hydrochloric and orthophosphoric acids, and the Al 65 Co 20 Cu 15 alloy exhibits the highest corrosion resistance in sulfuric acid. In most of the analyzed acids, the surface of samples dissolves relatively uniformly, except the areas with more defective structures, which dissolve at higher rates.

The laws of the combined action of sigma-and pi-ligands on the electronic structure and thermodynamic parameters of Cu+ acidoaquachlorocomplexes were investigated using the method of quantum chemical modeling. It was found that anhydrous chloride complexes with molecules of unsaturated organic acids (acrylic, maleic, fumaric) have the best energy characteristics. They achieve the maximum binding energies of the central atom with the chloride ion (151 +/- 2 kJ/mol) and the organic ligand (130 +/- 1 kJ/mol), which are practically independent of the nature of the acid. The addition of water molecules to [Cu+(L)(Cl-)] is energetically beneficial in all cases. The value of Delta Er depends on the nature of the organic acid, its form of existence (molecules, anions), and the number of water molecules. Therefore, it varies in a wide range of values (10-60 kJ/mol). Hydration promotes the transition from sigma-bonding by the central atom of anionic forms of organic ligands to pi-bonding. Stable pi-complexes [Cu+(L)(Cl-)(H2O)] exist with all forms of the studied acids. At the same time, the transition from the molecular form of organic acids to the anionic one totally worsens both the energetics of sigma-bonds of Cu+ with chlorine anions and water molecules, as well as the energetics of pi-bonds. The antagonism of the combined action of sigma-ligands in [Cu+(L)(Cl-)(H2O)] was quantified by the change in the effective charge of the central atom. It was shown that in complexes with the molecular form of the studied unsaturated acids, chlorine anions reduce the electron donation of water molecules by 86 %, and water molecules reduce the electron donation of Cl- by 35 %.

The paper presents the results of a study of the possibility of the formation of maleate pi-complexes of atomic copper in an aqueous solution. Taking into account the existing equilibria, the conditions for the synthesis of an organometallic dispersion by cementation with metallic zinc of a CuSO4 solution containing maleic acid have been optimized. The composition of the powders was determined using energy dispersive spectroscopy, thermogravimetry, and complexometry. It was found that at a molar ratio of reagents Zn: Cu2+ < 0.5, only the monovalent copper complex [Cu(C4O4H3)(H2O)] was formed, while at molar ratios Zn : Cu2+ between 0.5 and 1, obtained composite mixtures consisted of [Cu(C4O4H3)(H2O)], H2O (adsorbed), and Cu (metal). The formation of the pi-complex of atomic copper [Cu(C4O4H4)] was not recorded. Due to the heterogeneity of the cementation process, the produced composites at Zn : Cu2+ >= 0.5 are inhomogeneous. The copper content within samples produced at Zn : Cu2+ = 1 varies widely: from 47 wt. % up to 74 wt. %.

In the present study, the structure and corrosion properties of quasicrystalline conventionally solidified Al65Co20Cu15 alloy cooled at 5 К/s were investigated. Structure was characterized by metallography, X-Ray diffraction, scanning electron microscopy, and energy dispersive spectroscopy. Corrosion properties were determined by gravimetric and potentiodynamic methods at room temperature. The investigations performed confirm the peritectic formation of stable quasicrystalline decagonal D-phase that coexists with crystalline Al4(Co,Cu)3 and Al3(Cu,Co)2 phases in the structure of Al65Co20Cu15 alloy. According to energy dispersive spectroscopy, the stoichiometric composition of D-phase is Al63Co24Cu13. The susceptibility of the Al65Co20Cu15 alloy to corrosion significantly decreases with increasing pH from 1.0 (acidic media) to 7.0 (neutral medium). A corrosion rate of the Al65Co20Cu15 alloy in the aqueous acidic solutions (pH=1.0) increases in the order HNO3®HCl®H2SO4®H3PO4. The mass of the specimens decreases in the solutions of H2SO4 or H3PO4 and increases in the solutions of HNO3 or HCl which relates to different rate ratios of accumulation and dissolution of corrosion products. The Al65Co20Cu15 alloy exhibits the highest corrosion resistance in the NaCl solution (pH=7.0) in which it corrodes under electrochemical mechanism with oxygen depolarization. The better corrosion resistance in sodium chloride solution is achieved due to the formation of passive chemical compounds blocking the surface. Free corrosion potential of the Al65Co20Cu15 alloy has value –0.43 V, the electrochemical passivity region extends from –1.0 V to –0.4 V, and a corrosion current density amounts to 0.18 mА/сm2. Depending on media, two typical surface morphologies are revealed after corrosion of quasicrystalline specimens of the Al65Co20Cu15 alloy. In the H2SO4 and H3PO4 acidic solutions, clean specimens’ surface due to its homogeneous dissolution is observed except for the more defective areas, such as boundaries of crystalline Al3(Cu,Co)2 phase containing less Co, which dissolve at a higher rate. In the HNO3, HCl or NaCl solutions, a porous layer on the surface is formed which is visually revealed as surface darkening. After staying in the NaCl solution, on the surface of the Al65Co20Cu15 alloy, the pits are also found due to preferential dissolution of components where the boundaries of Al3(Cu,Co)2 phase and flaws are located.

The structure, phase composition, electrochemical behavior, and corrosion resistance of high-entropy alloys Fe5CrCuNiMnSi and Fe5CоCuNiMnSi in as-cast and splat-quenched states were studied. A cooling rate estimated by splat-quenched film thickness was ~ 106 K/s. Selecting the components of the studied alloys was carried out basing on the criteria adopted in the literature for the composition of a high-entropy alloy such as calculations of the entropy and enthalpy of mixing, valence electron concentrations as well as the difference between the atomic radii of the components. Using X-ray diffraction analysis, the phase composition and crystal lattice parameters of the investigated high-entropy alloys were determined. It was established that the as-cast Fe5CоCuNiMnSi alloy is a solid solution with a face-centered cubic lattice, while the as-cast Fe5CrCuNiMnSi alloy contains two solid solutions with a face-centered and solid solution with body-centered cubic lattices. However, both spalt-quenched high-entropy alloys were solid solutions with a face-centered cubic lattice. The values of stationary potentials and areas of electrochemical stability of alloys as well as the density of corrosion currents were determined. It was shown that samples of the Fe5CrCuNiMnSi alloy behaved inertly in corrosion tests both in as-cast and in splat-quenched states.

Using chemical (zinc cementation) and electrochemical (cathodic deposition on titanium nitride) methods, copper microdispersions were obtained in the presence of maleic acid in an acidic solution CuSO4. It was complexonometrically established that electrochemically obtained copper powders are characterized by a high metal content (97.9 wt. %) and a small amount of non-metallic inclusions has been determined. But their dispersion under the action of maleic acid increases by an order of magnitude. The metal content is reduced to 39.7 wt. % in chemically obtained powders. The elemental composition of particles (wt. %) has been determined by energy-dispersive x-ray spectroscopy: C – 9.35, O – 25.76, Cu – 64.90. The presence of complexed water in the organometallic dispersion has been thermogravimetrically proved. These data, combined with the data of IR spectroscopy, led to the conclusion that the main component of the organometallic dispersion is the complex [Cu(C4H3O4)(H2O)2].

In this work the structure and corrosion behavior of quasicrystalline cast Al63Cu25Fe12 and Al63Co24Cu13 alloys in 5-% sodium chloride solution (рН 6.9–7.1) were investigated. The alloys were cooled at 5 К/s. The structure of the samples was studied by methods of quantitative metallography, X-ray analysis, and scanning electron microscopy. Corrosion properties were determined by potentiodynamic method. The made investigations confirm the formation of stable quasicrystalline icosahedral (i) and decagonal (D) phases in the structure of Al63Cu25Fe12 and Al63Co24Cu13 alloys correspondingly. In 5-% sodium chloride solution, the investigated alloys corrode under electrochemical mechanisms with oxygen depolarization. Compared with Al63Cu25Fe12 alloy, the value of free corrosion potential for Al63Co24Cu13 alloy changes in the positive direction (–0.66 V and –0.43 V, respectively), and its electrochemical passivity region extends due to the inhibition of anodic processes. A corrosion current density, calculated from (E,lg(i))-curve, for Al63Co24Cu13 alloy amounts to 0.18 mА/сm 2 and for Al63Cu25Fe12 alloy – to 0.20 mА/сm 2 . The lower corrosion resistance of Al63Cu25Fe12 alloy may be explained by the presence of iron-containing phases in its structure. Based on obtained results, the Al63Co24Cu13 alloy was recommended as coating material for rocket-and-space equipment working in marine climate.

Using the methods of quantum chemical modeling, the interaction of copper atoms with acrylic (HA), maleic (H2M), and fumaric (H2F) acids in the presence of water has been studied. It was established that water molecules, being electron-donor ligands, strengthen the (d pi-p pi)-interaction in n-complexes of Cu-0 with unsaturated organic acids. Eight stable structures with molecular forms of ligands (two with HA, three with H2M and H2F) were revealed, among which the most stable complexes are [Cuo(H2O)(HA)], [Cu-0(H2O)(2)(H2M) and [Cuo(H2O)(2)(H2F)]. Topological analysis of the electron density distribution at the node Cu(-C=C-) showed that only in one case ([Cu-0(H2O)(2)(H2F)]) copper atoms form molecular orbitals with both carbon atoms. In all other complexes, one carbon atom is involved in the formation of a pi-bond. In addition, a synergistic effect of pi-ligands on the binding energy of water molecules by copper atoms was found.

Using chemical (zinc cementation) and electrochemical (cathodic deposition on titanium nitride) methods, copper microdispersions were obtained in the presence of maleic acid in an acidic solution CuSO4. It was complexonometrically established that electrochemically obtained copper powders are characterized by a high metal content ( 97.9 wt. %) and a small amount of non-metallic inclusions has been determined. But their dispersion under the action of maleic acid increases by an order of magnitude. The metal content is reduced to 39.7 wt. % in chemically obtained powders. The elemental composition of particles (wt. %) has been determined by energy-dispersive x-ray spectroscopy: C - 9.35, O - 25.76, Cu - 64.90. The presence of complexed water in the organometallic dispersion has been thermogravimetrically proved. These data, combined with the data of IR spectroscopy, led to the conclusion that the main component of the organometallic dispersion is the complex [Cu(C4H3O4)(H2O)(2)].