Pub Date : 2022-11-25DOI: 10.33609/2708-129x.88.10.2022.55-69
Daisuke Noguchi
In the present study, the crystal structures of non-chelating EDTA molecules and their non-chelation salts in a zwitterionic state, along with the EDTA-chelates of alkali and alkaline earth metals, were searched and overviewed. 25 non-chelating molecules of EDTA, and zwitterions of ethylenediammonium-diacetate diacetic acid HOOC-CH2-(-OOC-CH2-)NH+-CH2-CH2-NH+(-CH2-COO-)-CH2-COOH and their salts (ethylenediammonium-tetraacetic acid (HOOC-CH2-)2NH+-CH2-CH2-NH+(-CH2-COOH)2, ethylenediammonium-acetate triacetic acid (HOOC-CH2-)2NH+-CH2-CH2-NH+(-CH2-COO-)-CH2-COOH, and ethylenediammonium-tetraacetate (-OOC-CH2-)2NH+-CH2-CH2-NH+(-CH2-COO-)2 with counterions), as well as 17 types of EDTA-chelates of alkali metal ions (Li+, Na+, K+, Rb+) and alkaline earth metal ions (Mg2+, Ca2+, Sr2+, Ba2+) were analyzed using data from the Cambridge Crystallographic Data Center (CCDC). Each intramolecular contact distance between nitrogen and oxygen atoms (NH+···O) has been examined and found to be around 2.7 Å. Investigation on the distribution of the intramolecular NH+··· NH+-distances of EDTA and non-chelated salts thereof also revealed that bulky counterion and certain crystal solvent molecules correspond to change in crystal packing, and that they influenced the conformers of EDTA molecules among gauche form to anti form. In the existing crystalline EDTA-chelates of alkali metals as well as alkaline earth metals, various coordination numbers (CN) and the denticity (к) of EDTA anions are displayed; CN 5 to 9, and tri- and hexadentate fashions. Intramolecular contact N···O and N···N distances correspond to the metal ion radii except for the case of Sr-EDTA chelate, probably due to differences of crystal packings in addition to the number of counterions and crystal solvent molecules. The existing data on crystalline EDTA and its salts have been gathered herein, which contributes to a further understanding and exploring applications hereafter.
{"title":"ANALYSIS OF SPECIALTIES OF CRYSTAL STRUCTURE FOR NON-CHELATE CONFORMATIONS OF ETHYLENE-DIAMINETETRAACETIC ACID AND ITS SALTS WITH ALKALI AND ALKALINE EARTH METALS","authors":"Daisuke Noguchi","doi":"10.33609/2708-129x.88.10.2022.55-69","DOIUrl":"https://doi.org/10.33609/2708-129x.88.10.2022.55-69","url":null,"abstract":"In the present study, the crystal structures of non-chelating EDTA molecules and their non-chelation salts in a zwitterionic state, along with the EDTA-chelates of alkali and alkaline earth metals, were searched and overviewed. 25 non-chelating molecules of EDTA, and zwitterions of ethylenediammonium-diacetate diacetic acid HOOC-CH2-(-OOC-CH2-)NH+-CH2-CH2-NH+(-CH2-COO-)-CH2-COOH and their salts (ethylenediammonium-tetraacetic acid (HOOC-CH2-)2NH+-CH2-CH2-NH+(-CH2-COOH)2, ethylenediammonium-acetate triacetic acid (HOOC-CH2-)2NH+-CH2-CH2-NH+(-CH2-COO-)-CH2-COOH, and ethylenediammonium-tetraacetate (-OOC-CH2-)2NH+-CH2-CH2-NH+(-CH2-COO-)2 with counterions), as well as 17 types of EDTA-chelates of alkali metal ions (Li+, Na+, K+, Rb+) and alkaline earth metal ions (Mg2+, Ca2+, Sr2+, Ba2+) were analyzed using data from the Cambridge Crystallographic Data Center (CCDC). Each intramolecular contact distance between nitrogen and oxygen atoms (NH+···O) has been examined and found to be around 2.7 Å. Investigation on the distribution of the intramolecular NH+··· NH+-distances of EDTA and non-chelated salts thereof also revealed that bulky counterion and certain crystal solvent molecules correspond to change in crystal packing, and that they influenced the conformers of EDTA molecules among gauche form to anti form. In the existing crystalline EDTA-chelates of alkali metals as well as alkaline earth metals, various coordination numbers (CN) and the denticity (к) of EDTA anions are displayed; CN 5 to 9, and tri- and hexadentate fashions. Intramolecular contact N···O and N···N distances correspond to the metal ion radii except for the case of Sr-EDTA chelate, probably due to differences of crystal packings in addition to the number of counterions and crystal solvent molecules. The existing data on crystalline EDTA and its salts have been gathered herein, which contributes to a further understanding and exploring applications hereafter.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81859475","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-25DOI: 10.33609/2708-129x.88.10.2022.91-103
Leon Shteinberg
Arylamides of 3-hydroxy-2-naphthoic acid are widely used in the production of organic azo pigments, as medicines and pesticides. Titanium tetrachloride, tetrabutoxytitanium and polybutoxytitanates, previously used for the synthesis of the most important of them., 3-hydroxy-2-naphthoic acid anilide by boiling of the latter in aniline (184 °C), proved to be ineffective as catalysts in carrying out this reaction in ortho-xylene. The study of the reasons for this inhibition of catalysis showed that it can be associated with the interaction of Ti(4+) with the hydroxy group of 3-hydroxy-2-naphthoic acid, its oxidation, accompanied by a decrease in the effective charge of titanium. Taking into account this inhibition, in the search for new catalysts for the synthesis of 3-hydroxy-2-naphthoic acid anilide, the known literature data on the oxidizing ability (according to the values of the reaction rate constant k) with respect to phenoxyl radicals of a number of Lewis acids, including titanium tetrachloride, were used: SbCl5>TiCl4 >SnCl4>PCl5>AlCl3 k, l·mol-1·sec-1 105 157 156 42 18. This made it possible to choose phosphorus trichloride as an effective catalyst. It is shown that this compound, in an amount of only 2% mole. from 3-hydroxy-2-naphthoic acid, allows in boiling ortho-xylene (145 °C), under relatively mild conditions, compared to boiling aniline (184 °С), to obtain anilide 3-hydroxy-2-naphthoic acid (by reaction of the latter with aniline) of good quality with a practically quantitative yield. Antimony trifluoride also has similar properties as a catalyst, at the level of efficiency of phosphorus trichloride. The ability of catalysts to act as an oxidizing agent should, apparently, always be taken into account during the catalytic amidation of aromatic oxycarboxylic acids at elevated temperatures.
{"title":"СATALYTIC METHOD FOR THE SYNTHESIS OF 3-HYDROXY-2-NAPHTOIC ACID ANILIDE","authors":"Leon Shteinberg","doi":"10.33609/2708-129x.88.10.2022.91-103","DOIUrl":"https://doi.org/10.33609/2708-129x.88.10.2022.91-103","url":null,"abstract":"Arylamides of 3-hydroxy-2-naphthoic acid are widely used in the production of organic azo pigments, as medicines and pesticides. \u0000Titanium tetrachloride, tetrabutoxytitanium and polybutoxytitanates, previously used for the synthesis of the most important of them., 3-hydroxy-2-naphthoic acid anilide by boiling of the latter in aniline (184 °C), proved to be ineffective as catalysts in carrying out this reaction in ortho-xylene. \u0000The study of the reasons for this inhibition of catalysis showed that it can be associated with the interaction of Ti(4+) with the hydroxy group of 3-hydroxy-2-naphthoic acid, its oxidation, accompanied by a decrease in the effective charge of titanium. \u0000Taking into account this inhibition, in the search for new catalysts for the synthesis of 3-hydroxy-2-naphthoic acid anilide, the known literature data on the oxidizing ability (according to the values of the reaction rate constant k) with respect to phenoxyl radicals of a number of Lewis acids, including titanium tetrachloride, were used: \u0000SbCl5>TiCl4 >SnCl4>PCl5>AlCl3 \u0000k, l·mol-1·sec-1 105 157 156 42 18. \u0000This made it possible to choose phosphorus trichloride as an effective catalyst. It is shown that this compound, in an amount of only 2% mole. from 3-hydroxy-2-naphthoic acid, allows in boiling ortho-xylene (145 °C), under relatively mild conditions, compared to boiling aniline (184 °С), to obtain anilide 3-hydroxy-2-naphthoic acid (by reaction of the latter with aniline) of good quality with a practically quantitative yield. \u0000Antimony trifluoride also has similar properties as a catalyst, at the level of efficiency of phosphorus trichloride. \u0000The ability of catalysts to act as an oxidizing agent should, apparently, always be taken into account during the catalytic amidation of aromatic oxycarboxylic acids at elevated temperatures.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81540455","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-11-25DOI: 10.33609/2708-129x.88.10.2022.70-90
O. Boychuk
The review analyzes the physical and chemical properties of modified natural and artificial layered aluminosilicates, which form the basis for the emergence of thermoelectric properties in materials based on them. It represented the main methods of modification and analysis of structural and thermoelectric properties of these materials. Chemical modification of layered aluminosilicates is carried out by the reaction of solid aluminosilicate with concentrated aqueous solutions of metal hydroxides of groups I and II, their silicates, or phosphoric acid. The products of such interaction are called geopolymer. This name used to describe the reaction of the transformation of amorphous aluminosilicate into crystalline products during the interaction the solid product with concentrated alkali solutions of metals from the groups I and II, or the formation of composites and gel systems. The change in particle size, acidity of the media and impurity exchangeable cations in layered aluminosilicates significantly affects its acid-base and catalytic properties in aqueous solutions. The use of aqueous solutions increases the effect of hydrolytic processes on the number of hydroxide groups in the composition of the mineral, which are responsible for the adsorption properties and create the possibility of oxidative-destructive catalysis with the participation of the mineral. The ion-exchange capacity of layered aluminosilicates depends on the degree of their dispersion. The increasing degree of the Perdispersion level increases the ion-exchange capacity of the material. It is also possible to modify layered aluminosilicates with phosphoric acid, which can form polymers. Using phosphoric acid allows high temperatures over 900 C to change the electrical properties of minerals. The priority directions for strengthening the properties of heat-to-electricity conversion through the development of composite materials based on layered aluminosilicates using metal nanoparticles, silicon carbide, carbon, graphene, graphene-like materials, and metal oxides embedded in the aluminosilicate matrix have been established.
{"title":"THE NATURE AND CONDITIONS OF FORMATION OF THERMOELECTRIC PROPERTIES IN NATURAL AND ARTIFICIAL LAYERED ALUMOSILICATES","authors":"O. Boychuk","doi":"10.33609/2708-129x.88.10.2022.70-90","DOIUrl":"https://doi.org/10.33609/2708-129x.88.10.2022.70-90","url":null,"abstract":"The review analyzes the physical and chemical properties of modified natural and artificial layered aluminosilicates, which form the basis for the emergence of thermoelectric properties in materials based on them. It represented the main methods of modification and analysis of structural and thermoelectric properties of these materials. Chemical modification of layered aluminosilicates is carried out by the reaction of solid aluminosilicate with concentrated aqueous solutions of metal hydroxides of groups I and II, their silicates, or phosphoric acid. The products of such interaction are called geopolymer. This name used to describe the reaction of the transformation of amorphous aluminosilicate into crystalline products during the interaction the solid product with concentrated alkali solutions of metals from the groups I and II, or the formation of composites and gel systems. The change in particle size, acidity of the media and impurity exchangeable cations in layered aluminosilicates significantly affects its acid-base and catalytic properties in aqueous solutions. The use of aqueous solutions increases the effect of hydrolytic processes on the number of hydroxide groups in the composition of the mineral, which are responsible for the adsorption properties and create the possibility of oxidative-destructive catalysis with the participation of the mineral. The ion-exchange capacity of layered aluminosilicates depends on the degree of their dispersion. The increasing degree of the Perdispersion level increases the ion-exchange capacity of the material. It is also possible to modify layered aluminosilicates with phosphoric acid, which can form polymers. Using phosphoric acid allows high temperatures over 900 C to change the electrical properties of minerals. The priority directions for strengthening the properties of heat-to-electricity conversion through the development of composite materials based on layered aluminosilicates using metal nanoparticles, silicon carbide, carbon, graphene, graphene-like materials, and metal oxides embedded in the aluminosilicate matrix have been established.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-11-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79070669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-28DOI: 10.33609/2708-129x.88.09.2022.3-24
E. Trunova, M. Rusakova, T. Makotryk
New complexes of 3d-metals (Co2+, Ni2+, Zn2+) with bis(phosphonomethyl)aminosuccinic acid (H6BPMAS) have been synthesized. The complexes were studied in aqueous solutions at ratios M2+:H6BPMAS = 1:1 in a wide pH range (1÷10). Regardless of the nature of the metal, the formation of complexes of the general composition [M(HnBPMAS)(OH)m] (n= 4÷0, m=1÷0) is shown. The stability constants of the formed differently protonated complexes are calculated and diagrams of their distribution are plotted. It is shown that the process of complexation takes place most completely in the region of pH>4. For all bis(phosphonomethyl)aminosuccinates of 3d metals, the dominance of the complex with one form of the ligand occurs in approximately the same pH ranges. A close order of change in the values of lgKst. complexes testifies to the same type of structure of their internal coordination sphere. Solid complexes of the composition Na4[MBPMAS]⋅4H2O were synthesized. Their composition, structure, and thermal characteristics were determined by the set of methods such as diffuse reflectance spectroscopy, IR spectroscopy, DTA and non-quantitative mass spectrometry. It is proved that the complexes have the structure of a distorted octahedron, in which the 3-d metal ions are bound to the oxygen atoms of the carboxyl and phosphonic groups and the tertiary nitrogen atom of the ligand. At the same time, two 5-membered (aminomethylenephosphonic and glycine) and one 6-membered (β-alanine) metallocycles are formed in bis(phosphonomethyl)aminosuccinates. The biological activity of H6BPMAS and its complexes with Ni(II) and Co(II) against non-pathogenic bacterial species of microorganisms Pseudomonas fluorescens and Pseudomonas aureofaciens was studied. The study of the activity of substances was carried out in a liquid sterile Hiss medium. The maximum stimulating effect on the growth of bacterial cultures for the studied compounds was recorded at a concentration of 1 µM in 24 hours after the start of cultivation of microorganisms. The highest growth of microorganisms was recorded for metal complexes (50% Na4[CoBPMAS]·4H2O and 35% Na4[NiBPMAS]·4H2O). The maximum stimulating effect on the growth of bacterial cultures is shown by the Co(II) complex, which is able to initiate the synthesis of one of the most important growth hormones - heteroauxin.
{"title":"SYNTHESIS AND BIOLOGICAL ACTIVITY OF 3d-METAL COMPLEXES WITH BIS(PHOSPHONOMETHYL)AMINOSUNRIC ACID","authors":"E. Trunova, M. Rusakova, T. Makotryk","doi":"10.33609/2708-129x.88.09.2022.3-24","DOIUrl":"https://doi.org/10.33609/2708-129x.88.09.2022.3-24","url":null,"abstract":"New complexes of 3d-metals (Co2+, Ni2+, Zn2+) with bis(phosphonomethyl)aminosuccinic acid (H6BPMAS) have been synthesized. The complexes were studied in aqueous solutions at ratios M2+:H6BPMAS = 1:1 in a wide pH range (1÷10). Regardless of the nature of the metal, the formation of complexes of the general composition [M(HnBPMAS)(OH)m] (n= 4÷0, m=1÷0) is shown. The stability constants of the formed differently protonated complexes are calculated and diagrams of their distribution are plotted. It is shown that the process of complexation takes place most completely in the region of pH>4. For all bis(phosphonomethyl)aminosuccinates of 3d metals, the dominance of the complex with one form of the ligand occurs in approximately the same pH ranges. A close order of change in the values of lgKst. complexes testifies to the same type of structure of their internal coordination sphere. \u0000Solid complexes of the composition Na4[MBPMAS]⋅4H2O were synthesized. Their composition, structure, and thermal characteristics were determined by the set of methods such as diffuse reflectance spectroscopy, IR spectroscopy, DTA and non-quantitative mass spectrometry. It is proved that the complexes have the structure of a distorted octahedron, in which the 3-d metal ions are bound to the oxygen atoms of the carboxyl and phosphonic groups and the tertiary nitrogen atom of the ligand. At the same time, two 5-membered (aminomethylenephosphonic and glycine) and one 6-membered (β-alanine) metallocycles are formed in bis(phosphonomethyl)aminosuccinates. \u0000The biological activity of H6BPMAS and its complexes with Ni(II) and Co(II) against non-pathogenic bacterial species of microorganisms Pseudomonas fluorescens and Pseudomonas aureofaciens was studied. The study of the activity of substances was carried out in a liquid sterile Hiss medium. The maximum stimulating effect on the growth of bacterial cultures for the studied compounds was recorded at a concentration of 1 µM in 24 hours after the start of cultivation of microorganisms. The highest growth of microorganisms was recorded for metal complexes (50% Na4[CoBPMAS]·4H2O and 35% Na4[NiBPMAS]·4H2O). The maximum stimulating effect on the growth of bacterial cultures is shown by the Co(II) complex, which is able to initiate the synthesis of one of the most important growth hormones - heteroauxin.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87793627","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-28DOI: 10.33609/2708-129x.88.09.2022.34-40
Mariana Povidaichik, Oleksandr Shalimov, M. Onysko, P. Onysko
Amidines with a trichloromethyl group exhibit the properties of inotropic agents, which are used as scaffolds in synthesizing aza-heterocycles and ligands for complex formation. Functionalized amidines show anticancer, and antidiabetic activity, and are antihypertensive and antiparasitic agents. The synthesis of new functional derivatives of such amidines is definitely an urgent task. The introduction of an alkenyl substituent and several nucleophilic centers in the amidine creates prerequisites for electrophilic cyclization. This work aims to study the reactions of N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide with tellurium halides. The starting N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide was synthesized from N-allyl-N-methyl-2,2,2-trichloroethanimidamide by the action of trimethylsilyl chloride in the presence of triethylamine base. The reaction of N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide with tellurium dioxide in hydrohalic acid was carried out while cooling to 0°C. Elemental analysis confirms that the electrophilic reagent is in its acidic form in the complex. The 1H NMR spectra of the obtained complexes indicate the absence of EVC - the spin pattern of the proton signals of the allylic substituent, characteristic of the starting compounds, is preserved, but the signals are shifted by 0.3–0.6 ppm. The absence of proton signals of the trimethyl salt substituent indicates the removal of imide protection under these conditions. The presence of a broadened singlet in a weak field indicates the presence of acidic protons. Apparently, protonation does not take place on the alkenyl multiple bonds, but, presumably, on the imide nitrogen atom. Based on elemental analysis, the composition of the formed complex was determined: N-allyl-N-methyl-2,2,2-trichloroethanimidamidine: hexahalogenotelluric acid as 1:0.5, which contains 4 or 3 water molecules. So the interaction of N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide with tellurium tetrahalides in a strongly acidic environment, tellurium- or proton-induced cyclization does not occur, but hexahalogenotellurate N-allyl-N-methyl-2,2,2-trichloroethaneimidamidinium regardless of the polarity of the solvent.
具有三氯甲基的脒类具有肌力剂的性质，可作为合成杂氮杂环的支架和配合物的配体。功能化脒具有抗癌、抗糖尿病、抗高血压和抗寄生虫的作用。合成这类酰胺类新的功能衍生物无疑是一项紧迫的任务。在酰胺中引入一个烯基取代基和几个亲核中心为亲电环化创造了先决条件。本工作旨在研究n -烯丙基- n -甲基- n '-(三甲基硅基)-2,2,2-三氯乙酰胺与卤化碲的反应。以n -烯丙基- n -甲基-2,2,2-三氯乙胺为原料，在三乙胺碱存在下，通过三甲基硅氯的作用合成了n -烯丙基- n -甲基- n '-(三甲基硅基)-2,2,2-三氯乙胺。将N-烯丙基-N -甲基-N'-(三甲基硅基)-2,2,2-三氯乙酰胺与二氧化碲在氢盐酸中进行反应，冷却至0℃。元素分析证实亲电试剂在络合物中呈酸性。得到的配合物的1H NMR谱表明没有EVC -烯丙基取代基质子信号的自旋模式(起始化合物的特征)被保留，但信号移位了0.3-0.6 ppm。三甲基盐取代基的质子信号的缺失表明在这些条件下亚胺保护的去除。弱场中宽需单重态的存在表明酸性质子的存在。显然，质子化不会发生在烯基多键上，而可能发生在亚胺氮原子上。通过元素分析，确定了所形成的配合物的组成:n -烯丙基- n -甲基-2,2,2-三氯乙胺:六卤碲酸为1:0.5，其中含有4个或3个水分子。因此，在强酸性环境下，n-烯丙基- n-甲基- n '-(三甲基硅基)-2,2,2-三氯乙酰胺与四卤碲不会发生相互作用，而与溶剂的极性无关，六卤基-碲酸盐n-烯丙基- n-甲基-2,2,2-三氯乙基-内咪脒不会发生环化。
{"title":"SYNTHESIS OF SALTS OF N-ALLYLTRICHLOROACETAMIDINIUM HEXAHALOGENOTELLURATE","authors":"Mariana Povidaichik, Oleksandr Shalimov, M. Onysko, P. Onysko","doi":"10.33609/2708-129x.88.09.2022.34-40","DOIUrl":"https://doi.org/10.33609/2708-129x.88.09.2022.34-40","url":null,"abstract":"Amidines with a trichloromethyl group exhibit the properties of inotropic agents, which are used as scaffolds in synthesizing aza-heterocycles and ligands for complex formation. Functionalized amidines show anticancer, and antidiabetic activity, and are antihypertensive and antiparasitic agents. The synthesis of new functional derivatives of such amidines is definitely an urgent task. The introduction of an alkenyl substituent and several nucleophilic centers in the amidine creates prerequisites for electrophilic cyclization. This work aims to study the reactions of N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide with tellurium halides. \u0000The starting N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide was synthesized from N-allyl-N-methyl-2,2,2-trichloroethanimidamide by the action of trimethylsilyl chloride in the presence of triethylamine base. The reaction of N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide with tellurium dioxide in hydrohalic acid was carried out while cooling to 0°C. Elemental analysis confirms that the electrophilic reagent is in its acidic form in the complex. The 1H NMR spectra of the obtained complexes indicate the absence of EVC - the spin pattern of the proton signals of the allylic substituent, characteristic of the starting compounds, is preserved, but the signals are shifted by 0.3–0.6 ppm. The absence of proton signals of the trimethyl salt substituent indicates the removal of imide protection under these conditions. The presence of a broadened singlet in a weak field indicates the presence of acidic protons. Apparently, protonation does not take place on the alkenyl multiple bonds, but, presumably, on the imide nitrogen atom. Based on elemental analysis, the composition of the formed complex was determined: N-allyl-N-methyl-2,2,2-trichloroethanimidamidine: hexahalogenotelluric acid as 1:0.5, which contains 4 or 3 water molecules. So the interaction of N-allyl-N-methyl-N'-(trimethylsilyl)-2,2,2-trichloroethanimidamide with tellurium tetrahalides in a strongly acidic environment, tellurium- or proton-induced cyclization does not occur, but hexahalogenotellurate N-allyl-N-methyl-2,2,2-trichloroethaneimidamidinium regardless of the polarity of the solvent. \u0000 ","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84125757","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-28DOI: 10.33609/2708-129x.88.09.2022.41-51
Оleksandra Berezhnytska, O. Rohovtsov, O. Chyhyrynets, Denys Snihur
Spherical silver nanoparticles were synthesized by the chemical condensation method using aloe vera or chamomile extracts as a reducing agent. Depending on the type of extracts and its concentration, the size of AgNpcs varied from 7 to 50 nm by simply adjusting the ratio of the starting reagents. These extracts show reducing properties due to the presence of carbonyl compounds in their composition, in particular organic acids. It is shown that regulation of concentrations and synthesis conditions allows control of particle size. A change in the synthesis conditions affects the position of the surface plasmon resonance band, and therefore the optical properties of the studied systems. It has been proven that the synthesized silver nanoparticles do not require additional stabilization. Agglomeration processes occur only with a significant increase in concentration and heating time.
{"title":"GREEN SYNTHESIS OF SILVER NANOPARTICLES AND THEIR SPECTRAL PROPERTIES","authors":"Оleksandra Berezhnytska, O. Rohovtsov, O. Chyhyrynets, Denys Snihur","doi":"10.33609/2708-129x.88.09.2022.41-51","DOIUrl":"https://doi.org/10.33609/2708-129x.88.09.2022.41-51","url":null,"abstract":"Spherical silver nanoparticles were synthesized by the chemical condensation method using aloe vera or chamomile extracts as a reducing agent. Depending on the type of extracts and its concentration, the size of AgNpcs varied from 7 to 50 nm by simply adjusting the ratio of the starting reagents. These extracts show reducing properties due to the presence of carbonyl compounds in their composition, in particular organic acids. It is shown that regulation of concentrations and synthesis conditions allows control of particle size. A change in the synthesis conditions affects the position of the surface plasmon resonance band, and therefore the optical properties of the studied systems. It has been proven that the synthesized silver nanoparticles do not require additional stabilization. Agglomeration processes occur only with a significant increase in concentration and heating time.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78810250","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-10-28DOI: 10.33609/2708-129x.88.09.2022.25-33
O.J. Chorba, M. Filep, A. Pogodin, T. Malakhovska, M. Sabov
The technology of thermoelectric converters, based on the Peltier and Seebeck effects, provides a reversible process of convert in thermal and electrical energy. This opens up prospects for the creation of both thermoelectric coolers and thermoelectric generators. The most widely studied class of thermoelectric materials are complex chalcogenides. In recent years, copper-containing chalcogenides have been actively researched as new highly effective and ecologically friendly thermoelectric materials. The Cu–Sb–Se ternary system are characterized by the existence of three phases CuSbSe2, Cu3SbSe3 and Cu3SbSe4. Among these compounds, the Cu3SbSe3 phase is characterized by the lowest thermal conductivity. The synthesis of the Cu3SbSe3 polycrystalline alloy was carried out using high purity elementally components. The synthesis was carried out in vacuumed quartz ampoules by a one-temperature, two-stage process. Taking into account the incongruent melting of Cu3SbSe3, the single crystal growth was carried out by the method of vertical zone crystallization from a solution-melt in vacuumed conical quartz ampoules. As a result, the grown single crystal was dark gray color with metallic luster, without defects with length ~ 40 mm and diameter 12 mm. Obtained single crystalline sample of Cu3SbSe3 was investigated by DTA method. The heating curve contains one endothermic effect at 530°С, which corresponds to the process of peritectic decomposition of Cu3SbSe3. The effect corresponding to the melting of all components in the quartz container is not fixed. However, it is clearly visible on the cooling curve at 712 °С. The exothermic effect of crystallization of Cu3SbSe3 (503 °С) is clear and sharp and is observed with supercooling ΔТ = 27 °С. To confirm the single crystallinity of grown Cu3SbSe3 sample, an XRD analysis of the natural surface was carried out. The diffraction pattern shows two clear and narrow diffraction peaks corresponding to the (200) and (400) planes at angles of 22.27° and 45.42°, respectively. The crystal structure of the obtained Cu3SbSe3 single crystal was investigated by XRD analysis using the Rietveld full-profile refinement method. Established that Cu3SbSe3 crystallize in orthorhombic crystal system, SGPnma with lattice parameters: a = 7.9668 Å, b = 10.65870 Å, c = 6.8207 Å, Z = 4.
热电变换器技术基于珀尔帖效应和塞贝克效应，提供了一种可逆的热能和电能转换过程。这为热电冷却器和热电发电机的创造开辟了前景。研究最广泛的一类热电材料是复杂硫属化合物。近年来，含铜硫族化合物作为一种高效、环保的新型热电材料得到了积极的研究。Cu-Sb-Se三元体系的特点是存在CuSbSe2、Cu3SbSe3和Cu3SbSe4三个相。在这些化合物中，Cu3SbSe3相的导热系数最低。采用高纯元素组分合成了Cu3SbSe3多晶合金。该合成是在真空石英安瓿中通过一个温度，两个阶段的过程进行的。考虑到Cu3SbSe3的不均匀熔融，在真空锥形石英安瓿中采用溶液熔体垂直区结晶法进行了单晶生长。结果表明，生长的单晶呈深灰色，具有金属光泽，无缺陷，长~ 40 mm，直径12 mm。用DTA法对所得Cu3SbSe3单晶样品进行了研究。升温曲线在530°С处存在一个吸热效应，对应于Cu3SbSe3的包晶分解过程。石英容器内各组分熔化所对应的效果是不固定的。然而，它在712°С的冷却曲线上清晰可见。Cu3SbSe3(503°С)在过冷ΔТ = 27°С时发生了明显的放热结晶。为了证实生长的Cu3SbSe3样品的单晶性，对其自然表面进行了XRD分析。衍射图显示(200)面和(400)面分别以22.27°和45.42°夹角对应两个清晰窄的衍射峰。采用Rietveld全剖面细化法对所得Cu3SbSe3单晶的晶体结构进行了XRD分析。建立Cu3SbSe3在正交晶系中结晶，SGPnma晶格参数为:a = 7.9668 Å， b = 10.65870 Å， c = 6.8207 Å， Z = 4。
{"title":"CRYSTALS GROWTH AND REFINEMENT OF THE Cu3SbSe3 CRYSTAL STRUCTURE","authors":"O.J. Chorba, M. Filep, A. Pogodin, T. Malakhovska, M. Sabov","doi":"10.33609/2708-129x.88.09.2022.25-33","DOIUrl":"https://doi.org/10.33609/2708-129x.88.09.2022.25-33","url":null,"abstract":"The technology of thermoelectric converters, based on the Peltier and Seebeck effects, provides a reversible process of convert in thermal and electrical energy. This opens up prospects for the creation of both thermoelectric coolers and thermoelectric generators. The most widely studied class of thermoelectric materials are complex chalcogenides. In recent years, copper-containing chalcogenides have been actively researched as new highly effective and ecologically friendly thermoelectric materials. The Cu–Sb–Se ternary system are characterized by the existence of three phases CuSbSe2, Cu3SbSe3 and Cu3SbSe4. Among these compounds, the Cu3SbSe3 phase is characterized by the lowest thermal conductivity. \u0000The synthesis of the Cu3SbSe3 polycrystalline alloy was carried out using high purity elementally components. The synthesis was carried out in vacuumed quartz ampoules by a one-temperature, two-stage process. Taking into account the incongruent melting of Cu3SbSe3, the single crystal growth was carried out by the method of vertical zone crystallization from a solution-melt in vacuumed conical quartz ampoules. As a result, the grown single crystal was dark gray color with metallic luster, without defects with length ~ 40 mm and diameter 12 mm. \u0000Obtained single crystalline sample of Cu3SbSe3 was investigated by DTA method. The heating curve contains one endothermic effect at 530°С, which corresponds to the process of peritectic decomposition of Cu3SbSe3. The effect corresponding to the melting of all components in the quartz container is not fixed. However, it is clearly visible on the cooling curve at 712 °С. The exothermic effect of crystallization of Cu3SbSe3 (503 °С) is clear and sharp and is observed with supercooling ΔТ = 27 °С. To confirm the single crystallinity of grown Cu3SbSe3 sample, an XRD analysis of the natural surface was carried out. The diffraction pattern shows two clear and narrow diffraction peaks corresponding to the (200) and (400) planes at angles of 22.27° and 45.42°, respectively. The crystal structure of the obtained Cu3SbSe3 single crystal was investigated by XRD analysis using the Rietveld full-profile refinement method. Established that Cu3SbSe3 crystallize in orthorhombic crystal system, SGPnma with lattice parameters: a = 7.9668 Å, b = 10.65870 Å, c = 6.8207 Å, Z = 4.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-10-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77336620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-26DOI: 10.33609/2708-129x.88.08.2022.66-78
O. Kovalenko
In the process of obtaining barium titanate by the Pechini method, a connection between the conditions of complexes precipitation and the nature of their thermal decomposition was established. X-ray phase analysis of thermally decomposed precursors showed that the formation of a single-phase system based on barium titanate can be achieved in the range of Ba/Ti ratio 0.96-1.01 at high reagent concentration and low solution pH during the precursor deposition process. On the basis of thermogravimetric analysis, a possible mechanism of precursor decomposition and its composition is assumed. It is shown that the number of hydroxide groups in the structure affects the crystallization mechanism, total mass loss, and the amount of water adsorbed on the surface. In particular, samples obtained at low solution pH have a minimal amount of hydroxyl groups and decompose according to a typical four-step mechanism of thermal decomposition of barium titanyl oxalate. Other samples contain hydro and carbo groups, which leads to an increase in the final decomposition temperature above 770 °C and a multistage decomposition process due to the difference in the activation energy of the nucleation of different phases. This, in turn, may determine the dominance of the nucleation process over the growth and nucleation of smaller crystallites, compared to the product of pure oxalate decomposition. On the one hand, the high content of chloride ions at the lowest pH promotes the crystallization of the product and the formation of additional nucleation centers from the phase of amorphous titanium dioxide. On the other hand, the formation of smaller crystallites occurs due to the absence of significant particle collisions in conditions of low concentration of the solution. On the basis of thermogravimetric analysis, it is shown that at high concentration, barium titanyl oxalate decomposes mainly by the mechanism of formation of intermediate oxycarbonates, and not barium carbonate and titanium dioxide. Thus, the optimization of the precursor precipitation parameters and the study of the barium titanate formation mechanism allow for better regulation of the composition and crystallite size of the final product.
{"title":"THE INFLUENCE OF THE PRECURSOR COMPOSITION ON THE PECULIARITIES OF THE BARIUM TITANATE FORMATION","authors":"O. Kovalenko","doi":"10.33609/2708-129x.88.08.2022.66-78","DOIUrl":"https://doi.org/10.33609/2708-129x.88.08.2022.66-78","url":null,"abstract":"In the process of obtaining barium titanate by the Pechini method, a connection between the conditions of complexes precipitation and the nature of their thermal decomposition was established. X-ray phase analysis of thermally decomposed precursors showed that the formation of a single-phase system based on barium titanate can be achieved in the range of Ba/Ti ratio 0.96-1.01 at high reagent concentration and low solution pH during the precursor deposition process. On the basis of thermogravimetric analysis, a possible mechanism of precursor decomposition and its composition is assumed. It is shown that the number of hydroxide groups in the structure affects the crystallization mechanism, total mass loss, and the amount of water adsorbed on the surface. In particular, samples obtained at low solution pH have a minimal amount of hydroxyl groups and decompose according to a typical four-step mechanism of thermal decomposition of barium titanyl oxalate. Other samples contain hydro and carbo groups, which leads to an increase in the final decomposition temperature above 770 °C and a multistage decomposition process due to the difference in the activation energy of the nucleation of different phases. This, in turn, may determine the dominance of the nucleation process over the growth and nucleation of smaller crystallites, compared to the product of pure oxalate decomposition. On the one hand, the high content of chloride ions at the lowest pH promotes the crystallization of the product and the formation of additional nucleation centers from the phase of amorphous titanium dioxide. On the other hand, the formation of smaller crystallites occurs due to the absence of significant particle collisions in conditions of low concentration of the solution. On the basis of thermogravimetric analysis, it is shown that at high concentration, barium titanyl oxalate decomposes mainly by the mechanism of formation of intermediate oxycarbonates, and not barium carbonate and titanium dioxide. Thus, the optimization of the precursor precipitation parameters and the study of the barium titanate formation mechanism allow for better regulation of the composition and crystallite size of the final product.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83866774","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-26DOI: 10.33609/2708-129x.88.08.2022.97-105
O. Linyucheva, K. Pershina
The surface structure and nature of the capacitance formation of RuO2/Ti and TiO2 /Ti films are discussed. The factors affecting the reversibility of the adsorption-desorption processes of oxygen on the surface of RuO2/Ti and TiO2 /Ti films are described. The influence of the geometry of the pore, ruthenium content, thickness of the films, and the capacitance value of oxide films was studied using electron microscopy and electrochemical impedance spectroscopy. The changes in pore content and their geometry depending on Ru concentration are fixed by electron microscopy. The changing capacitance and capacitance dispersion in a wide frequency range was used to obtain 3D images of the film's surface. A scheme of the adsorption-absorption ratio changing in relation to the pore’s structure of the films was proposed. The study of the composition, morphological structure and electrochemical behaviour of RuO2/Ti and TiO2 /Ti films determined the impact of the pore shape of surface films on the adsorption-absorption ratio of oxygen, which regulated technical data of sensors. By changing the capacitance and capacitance dispersion in a wide frequency range, it was proposed to obtain 3D images of the surface. It was found that decrease of DEL capacitance has following relationships: large V-shaped pores on the boundary of titanium base and oxide film and on the surface of film > small V-shaped pores on the boundary of titanium base and oxide film, and large pores on the surface of film > rectangular-shaped pores on the boundary of titanium base and oxide film and small V-shaped pores on the surface of film. The formation of the pore geometry and surface structure is dependent on the ration of ruthenium and the thickness of films. So, it is possible to change the morphological and electrochemical properties of sensors by the regulation of ruthenium content.
{"title":"CORRELATION OF THE SURFACE STRUCTURE OF THE RuO2/TiAND TiO2 /TiFILMS WITH ELECTROCHEMICAL IMPEDANCE DATA","authors":"O. Linyucheva, K. Pershina","doi":"10.33609/2708-129x.88.08.2022.97-105","DOIUrl":"https://doi.org/10.33609/2708-129x.88.08.2022.97-105","url":null,"abstract":"The surface structure and nature of the capacitance formation of RuO2/Ti and TiO2 /Ti films are discussed. The factors affecting the reversibility of the adsorption-desorption processes of oxygen on the surface of RuO2/Ti and TiO2 /Ti films are described. The influence of the geometry of the pore, ruthenium content, thickness of the films, and the capacitance value of oxide films was studied using electron microscopy and electrochemical impedance spectroscopy. The changes in pore content and their geometry depending on Ru concentration are fixed by electron microscopy. The changing capacitance and capacitance dispersion in a wide frequency range was used to obtain 3D images of the film's surface. A scheme of the adsorption-absorption ratio changing in relation to the pore’s structure of the films was proposed. The study of the composition, morphological structure and electrochemical behaviour of RuO2/Ti and TiO2 /Ti films determined the impact of the pore shape of surface films on the adsorption-absorption ratio of oxygen, which regulated technical data of sensors. By changing the capacitance and capacitance dispersion in a wide frequency range, it was proposed to obtain 3D images of the surface. It was found that decrease of DEL capacitance has following relationships: large V-shaped pores on the boundary of titanium base and oxide film and on the surface of film > small V-shaped pores on the boundary of titanium base and oxide film, and large pores on the surface of film > rectangular-shaped pores on the boundary of titanium base and oxide film and small V-shaped pores on the surface of film. The formation of the pore geometry and surface structure is dependent on the ration of ruthenium and the thickness of films. So, it is possible to change the morphological and electrochemical properties of sensors by the regulation of ruthenium content.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85328462","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2022-09-26DOI: 10.33609/2708-129x.88.08.2022.59-65
K. Terebilenko, Valeriia Zozuliia, I. Tokmenko, M. Slobodyanik
The peculiarities of K2Gd(PO4)(MoO4) single crystal growth from combined phosphate-molybdate melts have been investigated. The formation regions of GdPO4, KGd(MoO4)2 and their cocrystallization fields with the mixed anionic compound potassium – gadolinium have been established. IR spectroscopy showed that in all compounds molybdenum and phosphorus are in a tetrahedral environment, and the phase composition was confirmed by X-ray powder. Crystallization of the target compound K2Gd(PO4)(MoO4) is observed in the pseudobinary section K2Mo2O7-KPO3 orthiorombic system, space group Ibca, Z = 8, а = 19,694(4) Å, b = 12,260(3) Å, c = 6,961(3) Å. Double phosphate K3Gd(PO4)2 crystallizes in the form of colorless prismatic crystals from the melts with the initial ratio K/P = 1.7–3.3, which practically corresponds to the section K2MoO4 – K4P2O7. Phosphate GdPO4 crystallizes in the form of colorless prismatic crystals up to 0.1 mm in size at the maximum KPO3 content in the melt, which corresponds to K/P ratio = 0.20–0.50 and K/(Mo+P) = 0.25–0.33. Crystal-chemical criteria for the formation of mixed-anion-type layered frameworks, island structures, and three-dimensional frameworks based on mixed phosphate-molybdate systems and rare earth elements are proposed. The key factor in the formation of complex oxide compounds of rare earth elements from combined molybdate-phosphate melts is the ratio of K/Mo in the initial solution - melt: 1) at K/Mo = 0.5–1.1, LnPO4 orthophosphates are formed, which are characterized by a 3D framework on the basis of LnO7/LnO8polyhedra condensed into a three-dimensional framework; at K/Mo = 1.2–1.5, mixed anionic compounds of the composition K2Ln(PO4)(MoO4) (Ln – Gd- Tb) with a layered structure are formed, where LnО8 forms zigzag chains; 3) at K/Mo = 1.6–3.0, double orthophosphates of the composition K3Ln(PO4)2 with an island structure are formed.
{"title":"GADOLINIUM(III) COMPLEX OXIDE COMPOUNDS OF OBTAINED FROM MOLYBDATE-PHOSPHATE MOLTEN SALT","authors":"K. Terebilenko, Valeriia Zozuliia, I. Tokmenko, M. Slobodyanik","doi":"10.33609/2708-129x.88.08.2022.59-65","DOIUrl":"https://doi.org/10.33609/2708-129x.88.08.2022.59-65","url":null,"abstract":"The peculiarities of K2Gd(PO4)(MoO4) single crystal growth from combined phosphate-molybdate melts have been investigated. The formation regions of GdPO4, KGd(MoO4)2 and their cocrystallization fields with the mixed anionic compound potassium – gadolinium have been established. IR spectroscopy showed that in all compounds molybdenum and phosphorus are in a tetrahedral environment, and the phase composition was confirmed by X-ray powder. Crystallization of the target compound K2Gd(PO4)(MoO4) is observed in the pseudobinary section K2Mo2O7-KPO3 orthiorombic system, space group Ibca, Z = 8, а = 19,694(4) Å, b = 12,260(3) Å, c = 6,961(3) Å. Double phosphate K3Gd(PO4)2 crystallizes in the form of colorless prismatic crystals from the melts with the initial ratio K/P = 1.7–3.3, which practically corresponds to the section K2MoO4 – K4P2O7. Phosphate GdPO4 crystallizes in the form of colorless prismatic crystals up to 0.1 mm in size at the maximum KPO3 content in the melt, which corresponds to K/P ratio = 0.20–0.50 and K/(Mo+P) = 0.25–0.33. Crystal-chemical criteria for the formation of mixed-anion-type layered frameworks, island structures, and three-dimensional frameworks based on mixed phosphate-molybdate systems and rare earth elements are proposed. The key factor in the formation of complex oxide compounds of rare earth elements from combined molybdate-phosphate melts is the ratio of K/Mo in the initial solution - melt: 1) at K/Mo = 0.5–1.1, LnPO4 orthophosphates are formed, which are characterized by a 3D framework on the basis of LnO7/LnO8polyhedra condensed into a three-dimensional framework; at K/Mo = 1.2–1.5, mixed anionic compounds of the composition K2Ln(PO4)(MoO4) (Ln – Gd- Tb) with a layered structure are formed, where LnО8 forms zigzag chains; 3) at K/Mo = 1.6–3.0, double orthophosphates of the composition K3Ln(PO4)2 with an island structure are formed.","PeriodicalId":23394,"journal":{"name":"Ukrainian Chemistry Journal","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2022-09-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83860379","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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