81 results on '"M. A. Shmelev"'
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2. Effect of the metal ion radius on the structure of SrII—ZnII and SrII—CdII complexes with cyclobutane-1,1-dicarboxylate anions
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E. N. Zorina-Tikhonova, N. V. Gogoleva, A. S. Chistyakov, P. Y. Khapaeva, M. A. Shmelev, A. A. Sidorov, M. A. Kiskin, and I. L. Eremenko
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General Chemistry - Published
- 2023
3. Two New Coordination Polymers of Cadmium with Bridging Thiocyanate Ligands: Composition and Structure
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V. V. Kovalev, Yu. V. Kokunov, M. A. Shmelev, Yu. K. Voronina, M. A. Kiskin, A. A. Sidorov, and I. L. Eremenko
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General Chemical Engineering ,General Chemistry - Published
- 2022
4. Zinc Pentafluorobenzoate [Zn2(H2O)(C6F5COO)4(Py)4]: Synthesis, Structure, and Thermodynamic Characteristics
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I. P. Malkerova, D. B. Kayumova, E. V. Belova, M. A. Shmelev, A. A. Sidorov, and A. S. Alikhanyan
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General Chemical Engineering ,General Chemistry - Published
- 2022
5. Heterometallic Ln(III)–Cd(II) Complexes with Anions of Monocarboxylic Acids: Synthetic Approaches and Analysis of Structures and Photoluminescence Properties
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M. A. Shmelev, N. V. Gogoleva, V. K. Ivanov, V. V. Kovalev, G. A. Razgonyaeva, M. A. Kiskin, A. A. Sidorov, and I. L. Eremenko
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General Chemical Engineering ,General Chemistry - Published
- 2022
6. Synthesis and Crystal Structure of {$${\text{Eu}}_{2}^{\text{III}}$$Cd2}, {$${\text{Tb}}_{2}^{{{\text{III}}}}$$Cd2} and {$$\text{Eu}_{2}^{\text{III}}$$Zn2} Complexes with Pentafluorobenzoic Acid Anions and Acetonitrile
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M. A. Shmelev, Yu. K. Voronina, N. V. Gogoleva, M. A. Kiskin, A. A. Sidorov, and I. L. Eremenko
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General Chemical Engineering ,General Chemistry - Published
- 2022
7. Monometallic Ln
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Y. A. Belousov, M. A. Kiskin, A. V. Sidoruk, E. A. Varaksina, M. A. Shmelev, N. V. Gogoleva, I. V. Taydakov, and I. L. Eremenko
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General Chemistry - Abstract
Four new complexes [Ln(pfaa)3(H2O)2]n (Ln = Eu (1), Tb (2)) and [Ln2Cd2(pfaa)10 (phen)2(EtOH)2]·2MeCN (Ln = Eu (3), Tb (4), phen = 1,10-phenanthroline) based on pentaphorphenylacetic acid (Hpfaa) have been prepared and completely investigated. The structures of compounds 1 and 3 were studied by single crystal X-ray diffraction analysis: the isostructural complexes 1 and 2 represent 1D coordination polymer, while the isostructural complexes 3 and 4 are molecular compounds. Complexes 1–4 show strong lanthanide-centred luminescence, since the introduction of phenanthroline leads to a significant increase in the observed lifetime (τobs) and photoluminescent quantum yield.
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- 2022
8. Thermodynamic Characteristics of Silver Perfluorobenzoates C6F5COOAg·0.5C6F5COOH and C6F5COOAg
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I. P. Malkerova, D. B. Kayumova, E. V. Belova, M. A. Shmelev, A. A. Sidorov, I. L. Eremenko, and A. S. Alikhanyan
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General Chemical Engineering ,General Chemistry - Published
- 2022
9. System of Electron Cyclotron Heating at the TRT Tokamak
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M. Yu. Shmelev, V. I. Belousov, and Gregory G. Denisov
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Physics ,Nuclear physics ,Tokamak ,Physics and Astronomy (miscellaneous) ,law ,Cyclotron ,Plasma ,Electron ,Condensed Matter Physics ,law.invention - Published
- 2021
10. Coordination polymers of VIV—MII (MII = Mn, Co, Ni, Cd) with ethylmalonate anions
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E. S. Bazhina, M. A. Shmelev, K. A. Babeshkin, N. N. Efimov, M. A. Kiskin, and I. L. Eremenko
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General Chemistry - Published
- 2021
11. Ultrastructural characteristics of erythrocytes and their relationship with oxygen transport in patients with ischemic heart disease after coronary artery bypass grafting with artificial circulation
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E. A. Sergeev, B. I. Geltser, M. E. Shmelev, and V. N. Kotelnikov
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Pulmonary and Respiratory Medicine ,medicine.medical_specialty ,Bypass grafting ,business.industry ,Oxygen transport ,Disease ,medicine.anatomical_structure ,Internal medicine ,Pediatrics, Perinatology and Child Health ,medicine ,Cardiology ,In patient ,Ischemic heart ,business ,Artery - Abstract
Aim. Evaluation of nanostructural and micromechanical characteristics of erythrocytes and their relationship with the parameters of oxygen transport in patients with ischemic heart disease (IHD) after coronary artery bypass grafting (CABG) under artificial circulation (AC).Materials and methods. The study involved 30 men with IHD aged 53 to 67 years with a median of 63 years, who underwent planned CABG with AC at the clinic of the Far Eastern Federal University. Blood sampling from patients was carried out before the AC and one day after it from a venous catheter located in the right atrium. Erythrocytes were scanned using a Bioscope Catalyst atomic force microscope (AFM) (Bruker, USA) in combination with an Axiovert 200 inverted microscope (Zeiss, Germany). The micromechanical properties of cell membranes were investigated with the PFQNM-LC-A-CAL cantilevers. The following were recorded: the diameter of erythrocytes, the height of their side, area, volume, membrane rigidity, strength of its adhesion, Young's modulus, elastic deformation. To assess oxygen transport, the oxygen delivery index (DO2I), consumption (VO2I), and extraction ratio (O2ER) were calculated.Results. In one day after CABG, a decrease in DO2I, VO2I, and O2ER was recorded by 14%, 33%, and 16%, respectively, which indicated a limitation in the gas transport function of the blood. Analysis of the AFM characteristics of erythrocytes showed an increase in their area by 35%, in diameter by 6%, in volume by 19%, and the height of the side by 5 times. At the same time, multidirectional changes in the micromechanical properties of erythrocyte membranes were noted: Young's modulus and stiffness decreased by 3.2 and 2 times, respectively; the adhesion force increased by 2.7 times, and the elastic deformation – by 2.2 times. Correlation analysis showed the presence of reliable relationships between indicators of oxygen transport and biomechanical parameters of erythrocyte membranes.Conclusion. A comprehensive analysis of the nanostructural parameters of erythrocytes and oxygen transport expands the understanding of the pathophysiological mechanisms of postperfusion disorders in patients with coronary artery disease after CABG under conditions of cardiopulmonary bypass.
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- 2021
12. Heterometallic Coii-Lii carboxylate complexes with N-heterocyclic carbene, triphenylphosphine and pyridine: a comparative study of magnetic properties
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M. A. Shmelev, Alexander S. Goloveshkin, Mikhail A. Kiskin, Maxim N. Sokolov, Stanislav A. Nikolaevskii, Nikolay N. Efimov, Denis V. Korchagin, Igor L. Eremenko, Dmitriy S. Yambulatov, Konstantin A. Babeshkin, and Pavel A. Petrov
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IMes ,chemistry.chemical_compound ,Magnetic anisotropy ,Crystallography ,Pivalic acid ,chemistry ,Phenylphosphine ,Pyridine ,General Chemistry ,Carboxylate ,Triphenylphosphine ,Carbene - Abstract
Heterometallic Coii-Lii compounds with N-heterocyclic carbene 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene (IMes), tri phenylphosphine (Ph3P) and pyridine (py), [Co2Li2(Piv)6(IMes)2] (Piv is the anion of pivalic acid), [Co2Li2(Piv)6(Ph3P)2] and [Co2Li2(Fur)6(py)2] (Fur is the anion of 2-furoic acid), respectively, have been prepared and structurally characterized by X-ray crystallography. Easy-plane magnetic anisotropy in Coii complexes with pseudo-tetrahedral cores CoO3X (X = C, P and N) was revealed by measuring the magnetic properties together with quantum-chemical calculations using the SA-CASSCF/NEVPT2 approach. The field-induced slow magnetic relaxation of the complexes was mainly attributed to the Raman and direct processes.
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- 2021
13. SYNTHESIS AND STRUCTURE OF AN NONTRIVIAL COORDINATION POLYMER {[Na2Co(pfb)2(H2O)8](pfb)2}n WITH PENTAFLUOROBENZOATE ANIONS
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M. A. Shmelev, K. A. Yashkova, Stanislav N. Melnikov, Mikhail A. Kiskin, Stanislav A. Nikolaevskii, Igor L. Eremenko, and Alexey A. Sidorov
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chemistry.chemical_classification ,Pentafluorobenzoic acid ,Solid-state physics ,Coordination polymer ,Cationic polymerization ,chemistry.chemical_element ,Polymer ,Chloride ,Inorganic Chemistry ,chemistry.chemical_compound ,chemistry ,Sodium hydroxide ,Polymer chemistry ,Materials Chemistry ,medicine ,Physical and Theoretical Chemistry ,Cobalt ,medicine.drug - Abstract
By the interaction of cobalt(II) chloride, sodium hydroxide, and pentafluorobenzoic acid (Hpfb) in water the first heterometallic complex of cobalt with pfb– anions is obtained. According to the X-ray crystallographic analysis, the complex is a cationic 1D polymer with the general formula {[Na2Co(pfb)2(H2O)8](pfb)2}n.
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- 2021
14. Coordination of Hexahydro-1,3,5-trimethyl-1,3,5-triazine in Cadmium(II) and Cobalt(II) Carboxylate Complexes
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S. S. Chekurova, O. I. Lyamina, Yu. K. Voronina, N. V. Gogoleva, T. M. Ivanova, M. A. Shmelev, E. V. Fatyushina, Igor L. Eremenko, Mikhail A. Kiskin, and Alexey A. Sidorov
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Pentafluorobenzoic acid ,Pivalic acid ,Ligand ,General Chemical Engineering ,Coordination number ,chemistry.chemical_element ,General Chemistry ,Medicinal chemistry ,chemistry.chemical_compound ,chemistry ,1,3,5-Triazine ,Moiety ,Carboxylate ,Cobalt - Abstract
The effect of bulky tridentate ligands on the geometry of carboxylate complexes was studied in relation to hexahydro-1,3,5-trimethyl-1,3,5-triazine (TACH). The reaction of [Co2Gd(NO3)(Piv)6(MeCN)2] (Piv is the pivalic acid anion) with TACH gave the complex [Co2Gd(NO3)(Piv)6(TACH)2] (I), in which the initial heterometallic moiety was retained and cobalt(II) ions coordinated the N-donor ligand to give a half-sandwich structure. The use of Cd(II) and Eu(III) pentafluorobenzoates in the reaction with TACH resulted in the isolation of only the homometallic complex [Cd(Pfb)2(TACH)2] (II) (Pfb is pentafluorobenzoic acid anion). Owing to high coordination number of cadmium(II) ion in II, a sandwich complex with two TACH molecules coordinated to the same metal ion was obtained. The structure of new complexes was determined by X-ray diffraction (CIF file CCDC nos. 2062230 (I) and 2062229 (II)). It was shown that binding of an N-donor ligand to a metal ion induces a significant distortion of the metal coordination polyhedra and a conformational change of hexahydro-1,3,5-trimethyl-1,3,5-triazine.
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- 2021
15. Heteroleptic cadmium(ii) and terbium(iii) pentafluorobenzoate-benzoate and pentafluorobenzoate-2-furancarboxylate compounds
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Igor L. Eremenko, Yu. V. Nelyubina, M. A. Shmelev, Fedor M. Dolgushin, N. V. Gogoleva, G. N. Kuznetsova, Mikhail A. Kiskin, and Alexey A. Sidorov
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Aqueous solution ,Coordination polymer ,Supramolecular chemistry ,Cationic polymerization ,chemistry.chemical_element ,Terbium ,General Chemistry ,Crystal structure ,law.invention ,chemistry.chemical_compound ,chemistry ,law ,Polymer chemistry ,Molecule ,Crystallization - Abstract
Heteroleptic cadmium(ii) carboxylates with anions of pentafluorobenzoic (pfb), benzoic (bz), and 2-furancarboxylic (fur) acids were prepared by the crystallization from aqueous solutions. The cadmium(ii) pentafluorobenzoate-benzoate complex is structurally similar to the starting compound [Cd(pfb)(H2O)4]n • n(pfb): bz anions are involved in the cationic 1D polymer {[Cd(bz)(H2O)3]n}n+, whereas pfb anions are outer-sphere. The pentafluorobenzoate-2-furan-carboxylate compound [Cd(fur)(pfb)(H2O)2]n•n(H2O) is a 1D coordination polymer. The heteroleptic TbIII complex [Tb2(bz)2(pfb)4(H2O)2(EtOH)2]•2Hbz has a molecular structure. The supramolecular crystal structures of the new compounds are stabilized by non-covalent interactions.
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- 2021
16. Molecular and Polymeric Cadmium Nitrate Complexes with Bridging 3-Aminoquinoline: Synthesis, Structures, and Luminescence Properties
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Leonid D. Popov, Vladimir Kovalev, Igor L. Eremenko, Mikhail A. Kiskin, Yu. K. Voronina, M. A. Shmelev, and Yu. V. Kokunov
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Denticity ,Hydrogen bond ,General Chemical Engineering ,Dimer ,Supramolecular chemistry ,Stacking ,General Chemistry ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallography ,Pentagonal bipyramidal molecular geometry ,chemistry ,Molecule ,Cadmium nitrate - Abstract
The reaction of Cd(NO3)2⋅4H2O with 3-aminoquinoline (3-Аq) affords the molecular and poly-meric complexes [Cd(NO3)2(H2O)(3-Аq)]⋅2MeCN (I) and {[Cd(NO3)2(3-Аq)2]⋅MeCN}n (II), respectively, depending on the ratio of the reagents and composition of the medium. Compounds I and II are studied by elemental analysis, X-ray structure analysis (CIF files CCDC nos. 2015059 (I) and 2015060 (II)), X-ray diffraction analysis, and luminescence investigation. In both cases, the environment of the cadmium atom is a pentagonal bipyramid. The 3-Аq molecules of dimer I are bridging ligands, and the monodentate mode of binding with Cd(II) along with the indicated function is observed in the polymer. Hydrogen bonds between the H atoms of the NH2 group and the N atom of the solvate MeCN molecule and the O atom of the NO3 group result in the formation of a three-dimensional supramolecular network, which is additionally strengthened by intermolecular stacking interactions between the aromatic fragments of 3-Аq of the adjacent molecules. Both compounds luminesce in the red spectral range. As compared to the spectrum of free 3-Аq, the shift of the emission bands of dimer I and polymer II in this range is 93 and 38 nm, respectively.
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- 2021
17. Isomerization of Binuclear Cadmium Carboxylate Complexes [Cd2L2(O2CR)4]
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A. G. Starikov, N. V. Gogoleva, Alexey A. Sidorov, Mikhail A. Kiskin, Igor L. Eremenko, and M. A. Shmelev
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Denticity ,Phenanthridine ,General Chemical Engineering ,General Chemistry ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Metal ,chemistry.chemical_compound ,Bipyridine ,chemistry ,visual_art ,visual_art.visual_art_medium ,Chelation ,Density functional theory ,Carboxylate ,Isomerization - Abstract
The binuclear cadmium complexes in which the metal atoms are linked by two chelate-bridging carboxylate anions, [Cd2L2(µ2-(Рiv)2(κO,κO'-(Рiv)2] (L is 2,4-lutidine, phenanthridine, and 2,2'-bipyridine; and Рiv is pivalate anion), and the complexes with the “Chinese lantern” structure in which the cadmium atoms are linked by four bridging carboxylate anions, [Cd2L2(µ2-(Рiv)4] (L is 2,3-cyclododecenopyridine (Сdpy)) and [Cd2(L)2(µ2-(PfAc))4] (L is 1,10-phenanthroline, and PfAc is pentafluorophenylacetate anion), are considered. The two-bridge and four-bridge isomers of each binuclear [Cd2L2(Рiv)4] complex with the monodentate and chelating N-donor ligands are calculated by the density functional theory using four different approximations. The stabilities of the isomers are compared and conclusions about the factors leading to the formation of complexes of this or another structure are made on the basis of the calculation data.
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- 2021
18. Structure Forming Role of Alkaline Metal Cations in the Formation of Chromium(III) Complexes with Anions of Cyclopropane-1,1-Dicarboxylic Acid
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M. A. Shmelev, Mikhail A. Kiskin, E. S. Bazhina, and Igor L. Eremenko
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chemistry.chemical_classification ,General Chemical Engineering ,Potassium ,chemistry.chemical_element ,General Chemistry ,Crystal structure ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,Alkali metal ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Cyclopropane ,chemistry.chemical_compound ,Chromium ,Dicarboxylic acid ,chemistry ,Chelation ,Lithium - Abstract
The reactions of Cr(NO3)3·9H2O with potassium, sodium, and lithium salts of cyclopropane-1,1-dicarboxylic acid (H2Cpdc) in a ratio of 1 : 3 are studied in order to elucidate the chemical assembling processes of the coordination polymers with Cr3+ and alkaline metal ions. The nature of the reacted alkaline metal cation affects the compositions and structures of the formed compounds. The reaction of Cr(NO3)3·9H2O with K2(Cpdc) affords the 3D polymeric complex [KCr(Cpdc)2(H2O)2]n (I) formed by the bis-chelate anionic fragments [Cr(Cpdc)2(H2O)2]–. Under similar conditions, the use of Na2(Cpdc) and Li2(Cpdc) results in the formation of the 3D polymers [Na4Cr(Cpdc)3(H2O)6(NO3)]n (II) and {[Li8Cr2(Cpdc)8(H2O)5]·H2O}n (III), respectively, containing the tris-chelate anionic fragments [Cr(Cpdc)3]3–. A distinctive feature of compound III is the presence in its structure of the {Li(Cpdc)}– fragments in which the Cpdc2– anion forms a six-membered chelate cycle with the Li+ ion. The crystal structures of compounds I–III are determined by X-ray diffraction (CIF files CCDC nos. 2031258 (I), 2031260 (II), and 2031261 (III)).
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- 2021
19. Influence of the Fluorinated Aromatic Fragments on the Structures of the Cadmium and Zinc Carboxylate Complexes Using Pentafluorobenzoates and 2,3,4,5-Tetrafluorobenzoates as Examples
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N. V. Gogoleva, Yu. K. Voronina, Fedor M. Dolgushin, Igor L. Eremenko, Alexey A. Sidorov, M. A. Shmelev, Mikhail A. Kiskin, Vladimir Ivanov, and G. N. Kuznetsova
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Cadmium ,Coordination polymer ,General Chemical Engineering ,Quinoline ,Stacking ,chemistry.chemical_element ,General Chemistry ,Zinc ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Intramolecular force ,Molecule ,Carboxylate - Abstract
A series of the cadmium and zinc carboxylate complexes with anions of pentafluorobenzoic (HРfbz) and 2,3,4,5-tetrafluorobenzoic (HТfbz) acids and N-donor ligands (1,10-phenanthroline (Phen) and quinoline (Quin)), [Cd(Pfbz)2(Phen)]n (I), [Cd(Рfbz)2(Рhen)2]·2MeCN (II), [Zn(H2O)-(Рfbz)2(Рhen)] (III), [Zn2Cd(Рfbz)6(Рhen)2]⋅2C6H6 (IV), [Cd2(H2O)2(Tfbz)4(Рhen)2] (V), [Cd2-(H2O)2(Tfbz)4(Quin)2] (VI), and [Cd(Tfbz)2(Phen)2]⋅HTfbz (VII), is synthesized. The structures of new complexes I–VII are determined by X-ray diffraction analysis (CIF files CCDC nos. 1871300, 2005461, 2005462, 2005464, 2005466, 2005465, and 2005459, respectively). The majority of the synthesized compounds is typical of intramolecular stacking interactions between the coordinated molecules of the aromatic N-donor ligands and fluorinated substituents of the carboxylate anions. These interactions lead to the formation of unusual compounds, which are different in the cases of pentafluorobenzoates and tetrafluorobenzoates, in particular, coordination polymer I and binuclear complexes V and VI with coordinated water molecules. The synthesized zinc and cadmium compounds differ in structure and composition.
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- 2021
20. Effect of Synthesis Conditions on the Composition and Structure of Chromium(III) Complexes with Cyclobutane-1,1-Dicarboxylic Acid Anions
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E. S. Bazhina, Alexander A. Korlyukov, M. A. Shmelev, Igor L. Eremenko, and Mikhail A. Kiskin
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chemistry.chemical_classification ,Recrystallization (geology) ,General Chemical Engineering ,chemistry.chemical_element ,General Chemistry ,Crystal structure ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,law.invention ,Cyclobutane ,chemistry.chemical_compound ,Chromium ,Dicarboxylic acid ,chemistry ,law ,Methanol ,Diethyl ether ,Crystallization - Abstract
The reaction of Cr(NO3)3·9H2O with potassium cyclobutane-1,1-dicarboxylate (K2(Cbdc)) in 1 : 3 ratio was studied. It was shown that, depending on the reaction conditions and the solvents used for synthesis and crystallization, compounds of various compositions and structures can be isolated from the reaction system. Conducting the reaction in water followed by recrystallization from ethanol and methanol results in isolation of 2D polymeric complexes [KCr(Cbdc)2(H2O)2]n (I) and {[K4Cr2(OMe)2(Cbdc)4(MeOH)6]· MeOH}n (II), respectively. The addition of excess KOH to the same reaction mixture and recrystallization from alcohols gives rise to the crystals of 3D polymeric compound [K3Cr(Cbdc)3(H2O)2]n (III). Conducting the reaction in methanol followed by slow diffusion of diethyl ether affords complex [K3Cr(Cbdc)3(MeOH)2(H2O)2]n (IV) with a 2D polymeric structure. The crystal structures of compounds I–IV were determined by X-ray diffraction (CIF files CCDC nos. 2006090 (I), 2006109 (II), 2006116 (III), and 2 006 117 (IV)).
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- 2021
21. BONDING FEATURES BETWEEN 2-PHENYLPYRIDINE AND 3d METAL IONS IN POLYNUCLEAR PIVALATES
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M. A. Shmelev, Stanislav A. Nikolaevskii, A. G. Starikov, Alexey A. Sidorov, G. N. Kuznetsova, Igor L. Eremenko, Dmitriy S. Yambulatov, and Mikhail A. Kiskin
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Quantum chemical ,chemistry.chemical_classification ,Materials science ,Solid-state physics ,Metal ions in aqueous solution ,Substituent ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,0104 chemical sciences ,Coordination complex ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,Transition metal ,chemistry ,Materials Chemistry ,Molecule ,2-Phenylpyridine ,Physical and Theoretical Chemistry - Abstract
The effect of a bulky phenyl substituent on the formation and stability of pivalate complexes of 3d transition metals is studied on the example of 2-phenylpyridine (phpy). Quantum chemical calculations in the B3LYP/Def2-TZVP approximation are used to optimize binuclear molecules of [M2(μ-piv)4L2] complexes, where M = Co, Ni, Cu, $$\text{piv} = \text{Me}_3\text{CCO}^-_2$$ , L = 2,3-lutidine (lut) for which the analyzed compounds are known, phpy, and 7,8-benzoquinoline (bquin). The calculated energy characteristics indicate a significant stability of lut complexes and suggest that similar compounds with phpy can be prepared. The accuracy of theoretical calculations is confirmed by the successful synthesis of complex [Cu2(piv)4(phpy)2] (3). The computational simulation of binuclear coordination compounds with bquin suggests that there is a theoretical possibility of their formation; however, the fact that such structures have lower stabilization energies than those of reference complexes ([M2(piv)4(DMF)2]) indicates that their preparative isolation is hindered. Molecular structures of novel molecular complexes [Ni9(OH)6(piv)12(Hpiv)2(phpy)]·C6H6 (2) and [Li2Co2(piv)6(phpy)2] (4) are isolated and determined.
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- 2021
22. Two types of Ln2Cu2 hydroxo-trimethylacetate complexes with 0D and 1D motifs: synthetic features, structural differences, and slow magnetic relaxation
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Nikolay N. Efimov, Igor S. Evstifeev, Anna A. Bovkunova, Mikhail A. Kiskin, E. S. Bazhina, Yulia V. Nelyubina, M. A. Shmelev, Igor L. Eremenko, and Konstantin A. Babeshkin
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chemistry.chemical_classification ,Lanthanide ,Relaxation (NMR) ,chemistry.chemical_element ,Polymer ,Copper ,Inorganic Chemistry ,Metal ,Crystallography ,chemistry.chemical_compound ,Magnetization ,chemistry ,visual_art ,visual_art.visual_art_medium ,Hydroxide ,Carboxylate - Abstract
Two series of heterometallic LnIII–CuII compounds containing a butterfly-like tetranuclear metal core were synthesized and characterized by X-ray diffraction and magnetometry. The structures of the new compounds were shown to depend on the nature of the hydroxide used for the synthesis. The reactions of copper(II) and lanthanide(III) salts with Hpiv (Hpiv is trimethylacetic acid) and LiOH in a MeCN–EtOH mixture afford the molecular complexes [Ln2Cu2(μ3-OH)2(piv)8(H2O)4]·4EtOH (1Ln, Ln = Gd, Tb, Dy, Ho, Yb), whereas the similar reactions using NaOH instead of LiOH give the 1D coordination polymers [Na2Ln2Cu2(μ3-OH)2(piv)10(EtOH)2]·EtOH (2Ln, Ln = Gd, Tb, Dy, Ho, Yb). According to ac susceptibility measurements, the DyIII–CuII compounds (1Dy and 2Dy) exhibit slow relaxation of magnetization indicative of single-molecule magnet (SMM) behavior. In the series of YbIII–CuII compounds, only complex 2Yb shows frequency-dependent out-of-phase ac susceptibility signals. This is the first reported example of carboxylate-based YbIII–CuII compound displaying slow magnetic relaxation.
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- 2021
23. Barium(II)–Chromium(III) Coordination Polymers Based on Dimethylmalonate Anions: Synthesis, Crystal Structure, Magnetic Properties, and EPR Spectra
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Alexander A. Korlyukov, Andrey V. Khoroshilov, Mikhail A. Kiskin, Nikolay N. Efimov, Denis V. Korchagin, Vadim V. Minin, M. A. Shmelev, Alyona A. Starikova, E. S. Bazhina, Sergey Yu. Kottsov, Konstantin A. Babeshkin, Igor L. Eremenko, and Elena A. Ugolkova
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Inorganic Chemistry ,chemistry.chemical_classification ,Chromium ,Chemistry ,law ,chemistry.chemical_element ,Physical chemistry ,Barium ,Polymer ,Crystal structure ,Electron paramagnetic resonance ,Spectral line ,law.invention - Published
- 2020
24. Copper(II) Trimethylacetate Complex with Caffeine: Synthesis, Structure, and Biological Activity
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I. A. Lutsenko, Olga B. Bekker, M. A. Kiskin, Vadim V. Minin, M. A. Shmelev, Alexey A. Sidorov, Dmitriy S. Yambulatov, N. N. Efimov, Elena A. Ugolkova, Stanislav A. Nikolaevskii, and Igor L. Eremenko
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General Chemical Engineering ,chemistry.chemical_element ,Biological activity ,General Chemistry ,Electronic structure ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Copper ,0104 chemical sciences ,Crystal ,chemistry.chemical_compound ,chemistry ,Anhydrous ,Chelation ,Caffeine ,Acetonitrile ,Nuclear chemistry - Abstract
The reaction of copper(II) trimethylacetate, [Cu(Piv)2]n (Piv = C(Me)3COO–), with caffeine (L) (Cu : L = 1 : 1) in anhydrous acetonitrile yielded the binuclear complex [Cu2(Piv)4(L)2] ⋅ 2CH3CN (I). The structure of the complex in the crystal was established by X-ray diffraction (CIF file CCDC no. 2 006 753), and the electronic structure was studied by ESR. The effect of caffeine coordination to the biogenic complexing agent was established: the in vitro biological activity of the obtained complex towards the non-pathogenic strain Mycolicibacterium smegmatis was eight times higher than that of free caffeine.
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- 2020
25. Microwave Setup of a Megawatt Power Level for the ECR Plasma Heating and Current Drive System of the T-15MD Tokamak
- Author
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Mikhail I. Bakulin, I. S. Baber, I. I. Leonov, K. A. Zhurin, P. P. Khvostenko, A. G. Eremeev, Gregory G. Denisov, A. V. Chirkov, E. A. Kopelovich, M. Yu. Glyavin, M. V. Kuznetsov, V. I. Malygin, B. Z. Movshevich, N. A. Kirneva, V. I. Belousov, Alexander I. Tsvetkov, E. M. Tai, E. A. Soluyanova, M. M. Troitskiy, N. I. Karpov, I. A. Varygin, I.O. Anashkin, M. Yu. Shmelev, and I. N. Roy
- Subjects
Physics ,Nuclear and High Energy Physics ,Tokamak ,Nuclear engineering ,Response time ,Astronomy and Astrophysics ,Statistical and Nonlinear Physics ,01 natural sciences ,Aspect ratio (image) ,010305 fluids & plasmas ,Electronic, Optical and Magnetic Materials ,Power (physics) ,law.invention ,Magnetic field ,law ,Transmission line ,Gyrotron ,0103 physical sciences ,Electrical and Electronic Engineering ,010306 general physics ,Microwave - Abstract
As part of the creation of a unique T-15MD tokamak with a magnetic field of 2 T and an aspect ratio of 2.2, the first one of a series (8 pieces) of microwave setups of a megawatt power level for electron–cyclotron plasma heating and current drive was developed and successfully tested. The setup includes a gyrotron, power supplies, a microwave radiation transmission line, and a fast (response time is no more than 10 μs) gyrotron emergency protection system. The generation regime was experimentally demonstrated with the parameters 1 MW/30 s/82.6 GHz for an efficiency of 57%.
- Published
- 2020
26. Development of Electrodynamic Components for Microwave Electronic Devices Using the Technology of 3D Photopolymer Printing with Chemical Surface Metallization
- Author
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A. E. Fedotov, N. Yu. Peskov, A. A. Vikharev, P. B. Makhalov, M. D. Proyavin, M. Yu. Shmelev, Dmitry I. Sobolev, and S. V. Kuzikov
- Subjects
Quantum optics ,Physics ,Nuclear and High Energy Physics ,Waveguide (electromagnetism) ,business.industry ,Astronomy and Astrophysics ,Statistical and Nonlinear Physics ,Undulator ,Laser ,01 natural sciences ,010305 fluids & plasmas ,Electronic, Optical and Magnetic Materials ,law.invention ,law ,0103 physical sciences ,Ribbon ,Cathode ray ,Optoelectronics ,Electronics ,Electrical and Electronic Engineering ,010306 general physics ,business ,Microwave - Abstract
We study the possibility of using the technology of 3D photopolymer printing with subsequent metallization of working surfaces for developing electrodynamic components of microwave devices. The technology applicability is considered by examples of mockups of a profiled helical waveguide for a microwave undulator of a Compton free-electron laser and a periodic slow-wave system of a backward-wave oscillator with a ribbon electron beam. The results of “cold” measurements of the parameters of these electrodynamic systems are presented and good agreement with the simulation results is obtained, which confirms the prospects of using additive technologies for developing components of the vacuum microwave electronic devices.
- Published
- 2020
27. Influence of the steric properties of pyridine ligands on the structure of complexes containing the {LnCd2(bzo)7} fragment
- Author
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Ilya V. Taydakov, Yu. V. Nelyubina, Yu. K. Voronina, G. G. Aleksandrov, F. M. Dolgushin, Mikhail A. Kiskin, N. V. Gogoleva, Igor L. Eremenko, E. A. Varaksina, M. A. Shmelev, and Alexey A. Sidorov
- Subjects
Lanthanide ,Steric effects ,Phenanthridine ,010405 organic chemistry ,General Chemistry ,010402 general chemistry ,01 natural sciences ,Pyridine ligand ,0104 chemical sciences ,Metal ,chemistry.chemical_compound ,Crystallography ,chemistry ,visual_art ,Acridine ,X-ray crystallography ,visual_art.visual_art_medium ,Luminescence - Abstract
The reaction of Cd(NO3)2 · 4H2O and Eu(NO3)3 · 6H2O or Tb(NO3)3 · 6H2O with potassium 3,5-di-tert-butylbenzoate (Kbzo) and N-donor ligands (1,10-phenanthroline (phen), 2,4-lutidine (2,4-lut), 3,4-lutidine (3,4-lut), phenanthridine (phtd), 2,3-cyclododecenopyridine (cdpy), acridine (acr)) afforded heterometallic LnCd2 complexes: [EuCd2(bzo)7(EtOH)2(phen)] (2), [LnCd2(bzo)7(2,4-lut)4] (Ln = Eu (3), Tb (4)), [EuCd2(bzo)7(H2O)2(2,4-lut)2] · MeCN (5), [EuCd2(NO3)(bzo)6(EtOH)2(2,4-lut)2] (6), [EuCd2(bzo)7(H2O)(EtOH)(3,4-lut)2] · 5EtOH (7), 3[EuCd2(bzo)7(H2O)2(phtd)2] · 4phtd (8), [EuCd2(bzo)7(EtOH)3(cdpy)] (9), 2[EuCd2-(bzo)2(EtOH)4] · acr (10). The structures of complexes 2, 3, and 5–10 were determined by single-crystal X-ray diffraction. The isostructurality of complexes 3 and 4 was confirmed by powder X-ray diffraction. The structure of the trinuclear {Ln2Cd} metal core is stable and independent of the type of peripheral ligands coordinated to cadmium atoms. Photoluminescent properties of compounds 3 and 4 were studied.
- Published
- 2020
28. Cd(II) and Cd(II)–Eu(III) Complexes with Pentafluorobenzoic Acid Anions and N-Donor Ligands: Synthesis and Structures
- Author
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G. N. Kuznetsova, N. V. Gogoleva, Yu. K. Voronina, Igor L. Eremenko, Ilya A. Yakushev, T. M. Ivanova, M. A. Shmelev, Yu. V. Nelyubina, Alexey A. Sidorov, and M. A. Kiskin
- Subjects
Pentafluorobenzoic acid ,General Chemical Engineering ,chemistry.chemical_element ,General Chemistry ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,0104 chemical sciences ,chemistry.chemical_compound ,Crystallography ,chemistry ,Pyridine ,Isoquinoline ,Europium - Abstract
The reactions of cadmium(II) and europium(III) pentafluorobenzoates ([Cd(Pfbz) $$\left( {{{{\text{H}}}_{{\text{2}}}}{\text{O}}} \right)_{{\text{4}}}^{ + }$$ }n ∙ n(Pfbz)–] (I) and [Eu2(Pfbz)6(H2O)8] ∙ 2H2O (II), respectively; Pfbz is pentafluorobenzoic acid anion) with the N-donor ligands (pyridine (Py), 2-phenylpyridine (Phpy), and 3-ethynylpyridine (Etypy)) afford a series of new Cd–Ln complexes with Pfbz– anions and Py or its substituted analogues: [Cd2Eu2(Pfbz)10(Py)4] (III), [Cd2Eu2(Pfbz)10(Phpy)2(MeCN)2] · 5MeCN (IV), and [CdEu2(Pfbz)8(Etypy)(H2O)2]n ∙ 3nMeCN ∙ n(Etypy) (VI). Similar reactions of compounds I and II with 2,4-lutidine (Lut), isoquinoline (Iquin), 2,2'-biquinoline (Biquin), and 7,8-benzoquinoline (Bquin) give the following cadmium complexes as the major products of crystallization from the reaction solutions: [Cd(Pfbz)2(Lut)]n (V), [Cd(H2O)(Pfbz)2(Iquin)2]n (VII), [Cd(Рfbz)2(Biquin)] (VIII), and $$[{\text{Cd}}{{({\text{Pfbz}})}_{{\text{3}}}}]_{n}^{-}$$ ∙ n(HBquin)+ (IX), respectively. The X-ray diffraction data (CIF files CCDC nos. 1987805 (I), 1987808 (III), 1987829 (IV), 1987817 (V), 1987822 (VI), 1987823 (VII), 1987824 (VIII), and 1987826 (IX)) are examples of the formation of new unusual coordination polymers.
- Published
- 2020
29. Chemical Assembling of Heterometallic {Cd–M} (M=Li, Mg, Eu, Tb) Molecules with 3,5‐Di‐ tert ‐butylbenzoate Bridges and N‐Donor Ligands
- Author
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Ilya V. Taydakov, Mikhail A. Kiskin, Alexey A. Sidorov, Grigory G. Aleksandrov, F. M. Dolgushin, Igor L. Eremenko, Yulia A. Nelyubina, Yulia K. Voronina, Natalia V. Gogoleva, Evgenia A. Varaksina, and M. A. Shmelev
- Subjects
Crystallography ,Chemistry ,X-ray crystallography ,Molecule ,General Chemistry ,Luminescence - Published
- 2020
30. Influence of Substituents in the Aromatic Fragment of the Benzoate Anion on the Structures and Compositions of the Formed {Cd–Ln} Complexes
- Author
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I. V. Taidakov, M. A. Shmelev, E. A. Varaksina, Konstantin A. Lyssenko, N. V. Gogoleva, Alexey A. Sidorov, M. A. Kiskin, Igor L. Eremenko, and Fedor M. Dolgushin
- Subjects
Pentafluorobenzoic acid ,Trifluoromethyl ,Ethanol ,General Chemical Engineering ,Potassium ,chemistry.chemical_element ,General Chemistry ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Ion ,chemistry.chemical_compound ,chemistry ,Aromatic fragment ,Isostructural ,Benzoic acid - Abstract
The reactions of Cd(NO3)2 ∙ 4H2O and Eu(NO3)3 ∙ 6H2O with potassium salts of the benzoic acid derivatives and 2,2'-bipyridine (Bipy) in ethanol, under the same synthesis conditions, afford the homo- and heterometallic complexes: [Eu2Cd2(BA)8(NO3)2(Bipy)2] (I, BA is benzoic acid anion), [Ln2Cd2(4-TBA)10(Bipy)2] (Ln = Eu (II), Tb (III); 4-TBA is 4-(trifluoromethyl)benzoic acid anion), [Cd(4-CBA)2(H2O)(Bipy)] (IV, 4-CBA is 4-cyanobenzoic acid anion), [Cd(PFBA)2(H2O)(Bipy)]n (V, PFBA is pentafluorobenzoic acid anion), and [Cd2(4-APFBA)4(Bipy)2] ∙ 4H2O (VI, 4-ATFBA is 4-amino-2,3,5,6-tetrafluorobenzoic acid anion). The structures of new complexes I, II, IV, and VI are determined by X-ray structure analysis (CIF files CCDC nos. 1970348, 1970350, 1970347, and 1970351, respectively). The isostructural character of complexes II and III is confirmed by X-ray diffraction analysis. The structures and compositions of the series of isolated compounds I–VI are determined by the nature of substituents in the benzoate anion. The photoluminescence properties of compounds II and III are studied.
- Published
- 2020
31. Synthesis of Coordination Polymers from the Heterometallic Carboxylate Complexes with Chelating N-Donor Ligands
- Author
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G. G. Aleksandrov, I. V. Taidakov, N. V. Gogoleva, Mikhail A. Kiskin, E. V. Aleksandrov, Igor L. Eremenko, Ilya A. Yakushev, E. A. Varaksina, M. A. Shmelev, Alexey A. Sidorov, Fedor M. Dolgushin, and D. A. Makarov
- Subjects
Terephthalic acid ,chemistry.chemical_classification ,Photoluminescence ,Structure analysis ,General Chemical Engineering ,General Chemistry ,Polymer ,010402 general chemistry ,010403 inorganic & nuclear chemistry ,01 natural sciences ,0104 chemical sciences ,Bipyridine ,chemistry.chemical_compound ,chemistry ,Polymer chemistry ,Molecule ,Chelation ,Carboxylate - Abstract
New trinuclear Cd–Ln molecular complexes [EuCd2(O2CC6F5)6(NO3)(Bipy)2] (I, Bipy is 2,2'-bipyridine) and [LnCd2(Bzo)6(NO3)(Phen)2] · 4MeCN (Ln = Tb (II), Eu (III), Bzo is anion of 3,5-di-tert-butylbenzoic acid, Phen is 1,10-phenanthroline) are studied. Their structures are determined by X-ray structure analysis (СIF files CCDC nos. 1938125 (I), 1938124 (II)) or by X-ray diffraction analysis (III), and the photoluminescence properties are studied. The reactions of complexes I and II with terephthalic acid (H2Bdc) are accompanied by the destruction of the heterometallic molecules to form 2D coordination polymers [Cd3(Bbdc)3(Bipy)2]3n · 4nMeCN · nH2O (IV) and [Cd2(Bdc)2(Phen)2]n · 2nDMF (V) (СIF files CCDC nos. 1938126 and 1937492, respectively).
- Published
- 2020
32. Facile synthesis and structure elucidation of metal-organic frameworks with {ZnCa} and {Zn2Ca} metal cores
- Author
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Irina K. Rubtsova, Julia K. Voronina, Igor L. Eremenko, Ilya A. Yakushev, Stanislav N. Melnikov, Mikhail A. Kiskin, M. A. Shmelev, Stanislav A. Nikolaevskii, Ekaterina D. Barabanova, and Alexey A. Sidorov
- Subjects
010405 organic chemistry ,Chemistry ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Metal ,chemistry.chemical_compound ,Crystallography ,visual_art ,Pyridine ,visual_art.visual_art_medium ,Metal-organic framework ,Topology (chemistry) - Abstract
The [ZnCa(DMF)2(tda)2]n·nDMF and [Zn2Ca(fda)4]n·2n(Me2NH2) metal-organic frameworks have been obtained by the reactions of pre-synthesized [Zn2Ca(piv)6(py)2] (piv is pivalate, and py is pyridine) with 2,5-thiophenedicarboxylic (H2tda) and 2,5-furandicarboxylic (H2fda) acids, respectively. Complex [Zn2Ca(piv)6(py)2] was used as a source of secondary building units with binuclear and trinuclear cores to form porous frameworks. The structure and topology of the compounds have been analyzed in detail.
- Published
- 2020
33. Cadmium-Inspired Self-Polymerization of {LnIIICd2} Units: Structure, Magnetic and Photoluminescent Properties of Novel Trimethylacetate 1D-Polymers (Ln = Sm, Eu, Tb, Dy, Ho, Er, Yb)
- Author
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Nikolay N. Efimov, Igor S. Evstifeev, Aleksey A. Sidorov, Nina P. Gritsan, Pavel N. Vasilyev, Natalia V. Gogoleva, M. A. Shmelev, Evgenia A. Varaksina, Igor L. Eremenko, Alexey A. Dmitriev, R. A. Polunin, Sergey V. Kolotilov, Mikhail A. Kiskin, and Ilya V. Taydakov
- Subjects
Materials science ,Pharmaceutical Science ,Organic chemistry ,010402 general chemistry ,01 natural sciences ,cadmium(II) ,Analytical Chemistry ,Magnetization ,symbols.namesake ,chemistry.chemical_compound ,X-ray diffraction study ,QD241-441 ,Ab initio quantum chemistry methods ,Magnetochemistry ,Drug Discovery ,Carboxylate ,Physical and Theoretical Chemistry ,Isostructural ,lanthanide(III) ,010405 organic chemistry ,Relaxation (NMR) ,pivalic acid ,0104 chemical sciences ,Crystallography ,coordination polymers ,chemistry ,ab initio calculations ,Chemistry (miscellaneous) ,symbols ,Molecular Medicine ,magnetochemistry ,photoluminescence ,Raman spectroscopy ,Luminescence ,heterometallic complexes - Abstract
A series of heterometallic carboxylate 1D polymers of the general formula [LnIIICd2(piv)7(H2O)2]n·nMeCN (LnIII = Sm (1), Eu (2), Tb (3), Dy (4), Ho (5), Er (6), Yb (7), piv = anion of trimethylacetic acid) was synthesized and structurally characterized. The use of CdII instead of ZnII under similar synthetic conditions resulted in the formation of 1D polymers, in contrast to molecular trinuclear complexes with LnIIIZn2 cores. All complexes 1–7 are isostructural. The luminescent emission and excitation spectra for 2–4 have been studied, the luminescence decay kinetics for 2 and 3 was measured. Magnetic properties of the complexes 3–5 and 7 have been studied, 4 and 7 exhibited the properties of field-induced single-molecule magnets in an applied external magnetic field. Magnetic properties of 4 and 7 were modelled using results of SA-CASSCF/SO-RASSI calculations and SINGLE_ANISO procedure. Based on the analysis of the magnetization relaxation and the results of ab initio calculations, it was found that relaxation in 4 predominantly occurred by the sum of the Raman and QTM mechanisms, and by the sum of the direct and Raman mechanisms in the case of 7.
- Published
- 2021
34. Vaporization Thermodynamics of Polymeric Cadmium Pivalate
- Author
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M. A. Shmelev, I. P. Malkerova, D. B. Kayumova, Igor L. Eremenko, Andrey S. Alikhanyan, and Alexey A. Sidorov
- Subjects
inorganic chemicals ,Cadmium ,Coordination sphere ,Chemistry ,Materials Science (miscellaneous) ,Enthalpy ,Inorganic chemistry ,technology, industry, and agriculture ,chemistry.chemical_element ,Mass spectrometry ,Inorganic Chemistry ,Metal ,visual_art ,Atom ,Vaporization ,visual_art.visual_art_medium ,Sublimation (phase transition) ,Physical and Theoretical Chemistry - Abstract
The vaporization of cadmium pivalate CdPiv2 with a polymeric structure was studied by the Knudsen effusion mass spectrometry of the gas phase. The sublimation of this complex was found to be congruent and to be accompanied by thermal dissociation with the formation of metal atoms and organic compounds due to its polymeric character. The standard enthalpies of vaporization were found, and the standard formation enthalpy of condensed cadmium pivalate was calculated. Highly volatile cadmium compounds could be synthesized via the introduction of additional ligands able to saturate the coordination sphere of the central atom.
- Published
- 2019
35. Thermodynamic Characteristics of the Cadmium Pivalate Phenanthroline Complex Cd2Piv4Phen2
- Author
-
M. A. Shmelev, I. P. Malkerova, Igor L. Eremenko, Alexey A. Sidorov, D. B. Kayumova, and Andrey S. Alikhanyan
- Subjects
Cadmium ,General Chemical Engineering ,Phenanthroline ,chemistry.chemical_element ,02 engineering and technology ,General Chemistry ,010402 general chemistry ,021001 nanoscience & nanotechnology ,01 natural sciences ,Dissociation (chemistry) ,Standard enthalpy of formation ,0104 chemical sciences ,chemistry.chemical_compound ,chemistry ,Ionization ,Physical chemistry ,Molecule ,Sublimation (phase transition) ,Knudsen number ,0210 nano-technology - Abstract
Evaporation of the cadmium pivalate phenanthroline complex Cd2Piv4Phen2 was studied by the Knudsen effusion method with mass spectral analysis of gas phase composition. The evaporation is congruent, and the gas phase consists of CdPiv2Phen molecules. The standard enthalpy of sublimation of these molecules was found. The energy of dissociation of CdPiv2Phen molecules to cadmium pivalate and phenanthroline was determined on the basis of experimental data on ionization.
- Published
- 2018
36. 3D printed photopolymer structures with chemically deposited copper for microwave electronics
- Author
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M.D. Proyavin, D.I. Sobolev, A.A. Vikharev, A.E. Fedotov, N. Yu. Peskov, M. Yu. Shmelev, S.V. Kuzikov, and P.B. Makhalov
- Published
- 2021
37. Formation of Polynuclear Cadmium Pivalates in Exchange Reactions
- Author
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N. V. Gogoleva, G. G. Aleksandrov, Mikhail A. Kiskin, Yu. V. Nelyubina, G. N. Kuznetsova, Alexey A. Sidorov, M. A. Shmelev, and Igor L. Eremenko
- Subjects
Cadmium ,010405 organic chemistry ,Chemistry ,General Chemical Engineering ,chemistry.chemical_element ,Physical chemistry ,Recrystallization (metallurgy) ,Infrared spectroscopy ,General Chemistry ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences - Abstract
The exchange reaction of CdCl2 ⋅ 2H2O with KPiv affords cadmium(II) trimethyl acetate complexes (K[Cd6(Piv)12Cl] ⋅ 2MeCN (I), [K2Cd3(Piv)8(H2O)6] (II), and [Cd(Piv)2(Н2О)2] (III) as a mixture with complex II and [K3Cd2(Piv)7(MeCN)2]n (IV) (HPiv is trimethylacetic acid). The exchange reaction of CdSO4 ⋅ 8/3H2O with Ba(Piv)2 makes it possible to obtain complex III in a quantitative yield. Complex III can also be isolated by the recrystallization of {Cd(Piv)2} from water. The recrystallization of complex III or {Cd(Piv)2} from MeCN affords hexanuclear complex [Cd6(Piv)12(MeCN)2] (V), which transforms into complex III upon recrystallization from water. All new compounds are characterized by the data of single-crystal X-ray diffraction analysis (CIF files CCDC no. 1572202–1572206), IR spectroscopy, and C,H,N analysis.
- Published
- 2018
38. Nickel(II) complexes with 2-Hfur and N-donors: The magnetic effects of the structural variations, thermal properties and antimycobacterial activity against Mycolicibacterium smegmatis
- Author
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Olga B. Bekker, Alexander S. Goloveshkin, Maria M. Petrova, I. A. Lutsenko, Petr V. Primakov, Nikolay N. Efimov, Ekaterina M. Zueva, Igor L. Eremenko, Mikhail A. Kiskin, Andrey V. Khoroshilov, M. A. Shmelev, M. A. Uvarova, Yulia V. Nelyubina, and Konstantin A. Babeshkin
- Subjects
010405 organic chemistry ,Chemistry ,Coordination polymer ,Thermal decomposition ,chemistry.chemical_element ,010402 general chemistry ,01 natural sciences ,Magnetic susceptibility ,0104 chemical sciences ,Inorganic Chemistry ,Metal ,Crystallography ,chemistry.chemical_compound ,Nickel ,visual_art ,Materials Chemistry ,visual_art.visual_art_medium ,Antiferromagnetism ,Physical and Theoretical Chemistry ,Thermal analysis ,Single crystal - Abstract
New complexes of nickel(II) with 2-furoic acid (2-Hfur) and different N-donor ligands of the composition [Ni(fur)2(phen)(H2O)2]·H2O (1) (phen = 1,10-phenantroline), [Ni(fur)2(2,2′-bpy)] (2, 2,2′-bpy = 2,2′-bipyridine), [Ni(fur)2(4,4′-bpy)(CH3OH)2]n (3, 4,4′-bpy = 4,4′-bipyridine), [Ni(fur)2(pz)4]·2MeCN (4) (pz = pyrazole) have been synthesized. The structure of the compounds was established by single crystal X-ray diffraction analysis. Complexes 1, 2, and 4 are mononuclear, complex 3 is a 1D coordination polymer. The DC magnetic susceptibility data measured for 2 and 3 are indicative of antiferromagnetic exchange interactions between the metal centers, which proved to be negligibly weak in 2 and more pronounced in 3. A quantum-chemical analysis of intermolecular (for 2) and intra- and interchain (for 3) magnetic exchange pathways confirms these findings, revealing the presence of magnetic chains formed by a network of very weak intermolecular antiferromagnetic exchange interactions in the crystal of 2 and a strengthening of antiferromagnetic exchange coupling in the polymeric chains of 3. Thermal behavior of 1 and 2 was studied by simultaneous thermal analysis (STA). According to PXRD data, the final thermolysis product of complex 2 is metal Ni nanocrystals (d = 14.7(3) nm). Analysis of the results of biological activity of 1–4 in vitro against Mycolicibacterium smegmatis showed a low sensitivity of the mycobacterial wall to Ni2+ cations.
- Published
- 2021
39. Polynuclear architectures with cadmium and lithium ions based on the {Li2Cd2(O2CCMe3)6} fragment
- Author
-
Mikhail A. Kiskin, Igor L. Eremenko, Alexey A. Sidorov, D. B. Kayumova, I. P. Malkerova, Konstantin A. Lyssenko, M. A. Shmelev, E.D. Barabanova, G. N. Kuznetsova, Alyona A. Starikova, N. V. Gogoleva, and Andrey S. Alikhanyan
- Subjects
Chemistry ,Coordination polymer ,02 engineering and technology ,010402 general chemistry ,021001 nanoscience & nanotechnology ,Condensed Matter Physics ,Mass spectrometry ,01 natural sciences ,Dissociation (chemistry) ,0104 chemical sciences ,Electronic, Optical and Magnetic Materials ,Ion ,Inorganic Chemistry ,chemistry.chemical_compound ,Crystallography ,Atom ,Materials Chemistry ,Ceramics and Composites ,Moiety ,Molecule ,Carboxylate ,Physical and Theoretical Chemistry ,0210 nano-technology - Abstract
Molecular [Li2Cd2(L)2(Piv)6]·Solv (Piv = trimethylacetate anion, L = 2,4-lutidine (1), 2,2′-bipyrdine (2), 2,2’:6′,2″-terpyridine (3),·Solv = 4MeCN (2)), chain [Li3Cd(MeCN)(THF)(Piv)5]n (4) and three-dimensional polymer [Li4Cd5(H2O)4(Piv)14]n.4H2O (5) complexes were synthesized and structurally characterized. All the new molecules contain the basic moiety {Li2Cd2(Piv)6} with the two central Li atoms connected with periphery CdII by bridging carboxylate anions. Molecular compounds 1–3 are stabilized by terminal N-donor ligands. In the chain of polymer 4 each CdII atom simultaneously belongs to the neighboring {Li2Cd2(Piv)4} moiety. The core in 5 is formed by connection the {Li2Cd2} units by the {Cd(Piv)2(H2O)4} tetradentate bridging moiety. The vaporization processes, thermodynamic characteristics of complex 2 and related dissociation products in condensed and gas phases were determined by mass spectrometry. Stability of 2 in the processes of hypothetical dissociation was additionally estimated by DFT-calculations.
- Published
- 2021
40. Coordination polymers based on 3,5-di-tert-butylbenzoate {Cd2Eu} moieties
- Author
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Mikhail A. Kiskin, Igor L. Eremenko, Evgenia A. Varaksina, M. A. Shmelev, Vladislav M. Korshunov, Julia K. Voronina, Natalia V. Gogoleva, Alexey A. Sidorov, Yulia V. Nelyubina, and Ilya V. Taydakov
- Subjects
chemistry.chemical_classification ,Ethylene ,Pyrazine ,010405 organic chemistry ,Ligand ,Polymer ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Inorganic Chemistry ,Metal ,chemistry.chemical_compound ,chemistry ,visual_art ,Excited state ,Materials Chemistry ,visual_art.visual_art_medium ,Molecule ,Physical and Theoretical Chemistry ,Single crystal - Abstract
Heterometallic complex [Cd2Eu(bzo)6(NO3)(MeCN)2(THF)2].2EtOH was synthesized by the reaction of Cd(NO3)2·4H2O and Eu(NO3)3·6H2O with potassium 3,5-di-tert-butylbenzoate (Hbzo). N-Donors (L) could replace solvents in the Cd coordination environment without modifying the stable metal core {Cd2Eu(bzo)6(X)} (X = NO3 or bzo). The presence of pyrazine (pz) in the reaction mixture could result in the formation of either molecular [Cd2Eu(bzo)6(NO3)(pz)2(EtOH)2] or 1D-polymeric [Cd2Eu(bzo)6(NO3)(pz)(H2O)2]n complex, depending on the Cd : L molar ratio (1 : 15 and 1 : 8, respectively). Addition of bridging N-donors 4,4′-bipyridine (4,4′-bipy) and 1,2-bis(2-pyridyl)ethylene (bpe) (Cd : L = 1 : 2) gave the [Cd2Eu(bzo)7(4,4′-bipy)(H2O)2]n and [Cd2Eu(bzo)7(bpe)(H2O)2]n polymers, respectively. 4-Methyl-2-aminopyridine (ampy) gave only molecular compound [Cd2Eu(bzo)7(ampy)2(EtOH)(H2O)] (Cd : L = 1 : 3). The structures of all the resulting compounds were studied by single crystal X-ray diffraction analysis. Photoluminescent properties were studied for solid samples of the synthesized compounds. The effect of the N-donor ligand geometry and the Eu…Eu distance on the lifetime of the Eu3+ atom’s 5D0 excited state is discussed.
- Published
- 2021
41. Molecular and Polymer Ln2M2 (Ln = Eu, Gd, Tb, Dy; M = Zn, Cd) Complexes with Pentafluorobenzoate Anions: The Role of Temperature and Stacking Effects in the Structure; Magnetic and Luminescent Properties
- Author
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Ilya V. Taydakov, Mikhail A. Kiskin, Natalia V. Gogoleva, M. A. Shmelev, Evgenia A. Varaksina, Vladislav M. Korshunov, Konstantin A. Babeshkin, Igor L. Eremenko, Alexey A. Sidorov, Julia K. Voronina, and Nikolay N. Efimov
- Subjects
Pentafluorobenzoic acid ,cadmium-lanthanide(III) complexes ,Coordination polymer ,pentafluorobenzoic acid ,chemistry.chemical_element ,Terbium ,Zinc ,010402 general chemistry ,lcsh:Technology ,01 natural sciences ,law.invention ,chemistry.chemical_compound ,single crystal X-ray ,law ,Magnetochemistry ,General Materials Science ,Crystallization ,lcsh:Microscopy ,lcsh:QC120-168.85 ,zinc-lanthanide(III) complexes ,lcsh:QH201-278.5 ,lcsh:T ,010405 organic chemistry ,0104 chemical sciences ,coordination polymer ,Crystallography ,chemistry ,lcsh:TA1-2040 ,magnetochemistry ,lcsh:Descriptive and experimental mechanics ,lcsh:Electrical engineering. Electronics. Nuclear engineering ,lcsh:Engineering (General). Civil engineering (General) ,Luminescence ,Europium ,lcsh:TK1-9971 - Abstract
Varying the temperature of the reaction of [{Cd(pfb)(H2O)4}+n·n(pfb)−], [Ln2(pfb)6(H2O)8]·H2O (Hpfb = pentafluorobenzoic acid), and 1,10-phenanthroline (phen) in MeCN followed by crystallization resulted in the isolation of two type of products: 1D-polymers [LnCd(pfb)5(phen)]n·1.5nMeCN (Ln = Eu (I), Gd (II), Tb (III), Dy (IV)) which were isolated at 25 °C, and molecular compounds [Tb2Cd2(pfb)10(phen)2] (V) formed at 75 °C. The transition from a molecular to a polymer structure becomes possible because of intra- and intermolecular interactions between the aromatic cycles of phen and pfb from neighboring tetranuclear Ln2Cd2 fragments. Replacement of cadmium with zinc in the reaction resulted in molecular compounds Ln2Zn2 [Ln2Zn2(pfb)10(phen)2]·4MeCN (Ln = Eu (VI), Tb (VIII), Dy (IX)) and [Gd2Zn2(pfb)10(H2O)2(phen)2]·4MeCN (VII). A new molecular EuCd complex [Eu2Cd2(pfb)10(phen)4]·4MeCN (X)] was isolated from a mixture of cadmium, zinc, and europium pentafluorobenzoates (Cd: Zn:Ln = 1:1: 2). Complexes II-IV, VII and IX exhibit magnetic relaxation at liquid helium temperatures in nonzero magnetic fields. Luminescent studies revealed a bright luminescence of complexes with europium(III) and terbium(III) ions.
- Published
- 2020
42. Influence of geometric and electronic features of pyridine derivatives and triethylamine on the formation of a metal carboxylate core in reactions producing cadmium(ii) pivalate complexes
- Author
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G. G. Aleksandrov, M. A. Shmelev, Alexey A. Sidorov, Mikhail A. Kiskin, N. V. Gogoleva, and Igor L. Eremenko
- Subjects
chemistry.chemical_classification ,Phenanthridine ,010405 organic chemistry ,Stereochemistry ,Substituent ,General Chemistry ,Crystal structure ,010402 general chemistry ,01 natural sciences ,Medicinal chemistry ,0104 chemical sciences ,Coordination complex ,chemistry.chemical_compound ,chemistry ,Pyridine ,Carboxylate ,Isoquinoline ,Triethylamine - Abstract
The reaction products of [Cd(piv)2] (piv is–O2CBut) with isoquinoline (iqn), 2,4-lutidine (lut), phenanthridine (phend), 2,3-cyclododecenopyridine (cpy), and triethylamine (Et3N) were synthesized and their structures were determined. The steric factors were found to play a more important role in cadmium(ii) pivalate complexes compared to 3d metal carboxylates in the +2 oxidation state. The reaction of [Cd(piv)2] with isoquinoline produces only the mononuclear complex [Cd(piv)2(iqn)3] (1). The reaction of [Cd(piv)2] with pyridine derivatives bearing a bulky substituent at the α position is accompanied by the formation of symmetrical dinuclear complexes of the composition [Cd2(piv)4(L)2]. In the complexes with L = lut (2) or phend (3), the cadmium(ii) atoms are linked by two chelating-bridging carboxylate groups; in the complex with L = cpy (4), by four bidentate-bridging groups. The reaction of [Cd(piv)2] with Et3N in a solution of MeCN gives the centrosymmetric linear trinuclear complex [Cd3(piv)6(Et3N)2] (6); in a mixture of benzene and hexane, the ionic compound (HEt3N)[Cd2(piv)5(H2O)] (7). The crystal structures of all synthesized compounds were determined by X-ray diffraction.
- Published
- 2016
43. Heterometallic trinuclear {CdII—MII—CdII} pivalates (M = Mg, Ca, or Sr): ways of assembly and structural features
- Author
-
Stanislav A. Nikolaevskii, Mikhail A. Kiskin, Igor L. Eremenko, Igor S. Evstifeev, Alexey A. Sidorov, G. G. Aleksandrov, Zh. V. Dobrokhotova, N. V. Gogoleva, and M. A. Shmelev
- Subjects
010405 organic chemistry ,Hydrogen bond ,Chemistry ,Ligand ,Dimer ,General Chemistry ,Crystal structure ,010402 general chemistry ,01 natural sciences ,0104 chemical sciences ,Crystallography ,chemistry.chemical_compound ,Intramolecular force ,X-ray crystallography ,Molecule ,Chelation - Abstract
Conditions for chemical assembly of new heterometallic trinuclear pivalates [Cd2M(piv)6L2] (M = Mg, Ca, or Sr; piv is pivalate) were found. Reactions with the nonchelating ligand 2,4-lutidine (lut) gave the crystals of heterometallic complexes [Cd2M(piv)6(lut)2] (M = Mg (1), Ca (2), and Sr (3)). With the chelating ligand 1,10-phenanthroline (phen), only the homometallic dimer [Cd2(piv)4(phen)2] (4) was obtained under these conditions. Yet heterometallic trinuclear complexes with 1,10-phenanthroline ([Cd2Mg(piv)6(H2O)(phen)2] (5), [CaCd2(piv)6(phen)2] (6), and [Cd2Sr(piv)6(phen)2]∙2MeCN (7)) were synthesized by reactions of phen with complexes 1—3. For all the complexes obtained, the molecular and crystal structures as well as the details of their molecular architecture were determined. The thermal behavior of aqua complex 5 was studied by TG and DSC. The complex eliminated the water molecule between 130 and 180 °C with a high endothermic effect (Q = 101 kJ mol–1) due to (1) intramolecular hydrogen bonds that stabilize its molecular architecture and (2) subsequent structural rearrangements.
- Published
- 2016
44. Power Combiner Based on the Talbot Effect in an Oversized Rectangular Waveguide
- Author
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M. Y. Shmelev and G. G. Denisov
- Subjects
Physics ,Radiation ,Optics ,business.industry ,Microwave signals ,Talbot effect ,Physics::Optics ,Classical electromagnetism ,Power combiner ,Electrical and Electronic Engineering ,Condensed Matter Physics ,business ,Instrumentation - Abstract
The paper presents the calculation of the power combiner of coherent microwave signals. The combiner is based on the Talbot effect in an oversized rectangular waveguide. Parameters of the combiner fed by one source were simulated and experimentally confirmed.
- Published
- 2015
45. Efficient approaches in synthesis and design of multi-mode units for mm and THz devices
- Author
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M. Yu. Glyavin, G. G. Denisov, Alexander I. Tsvetkov, A. G. Eremeev, Dmitry I. Sobolev, E.M. Tai, A. V. Chirkov, E. A. Solyayanova, A. N. Kuftin, and M. Yu. Shmelev
- Subjects
010302 applied physics ,Computer science ,business.industry ,Terahertz radiation ,0103 physical sciences ,Electronic engineering ,Mode (statistics) ,Optoelectronics ,business ,Microwave oscillators ,01 natural sciences ,Microwave ,010305 fluids & plasmas - Abstract
The paper discusses several approaches which allow development of microwave components with unique parameters. Results of two recent experiments illustrate practical value of the methods applied.
- Published
- 2017
46. 45GHz/20kW gyrotron setup with automated output power control for ECR ion source
- Author
-
M. V. Kuznetsov, E. M. Tai, Andrey P. Fokin, V. V. Kholoptsev, E. A. Soluyanova, M. Yu. Shmelev, A. G. Eremeev, I. V. Plotnikov, M. M. Troitskiy, Mikhail I. Bakulin, Mikhail V. Morozkin, K. A. Zhurin, Yu. V. Bykov, E. A. Kopelovich, M. Yu. Glyavin, A.Yu. Novikov, G. G. Denisov, and Alexander I. Tsvetkov
- Subjects
010302 applied physics ,Physics ,business.industry ,QC1-999 ,Electrical engineering ,01 natural sciences ,Ion source ,law.invention ,010309 optics ,law ,Gyrotron ,0103 physical sciences ,business ,Power control - Published
- 2017
47. Fast quasi-optical phase shifter based on the effect of induced photo conductivity in silicon
- Author
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M. Yu. Shmelev, Dmitry I. Sobolev, A. N. Stepanov, S. V. Kuzikov, A. A. Vikharev, Vladimir V. Parshin, G. G. Denisov, Vl. V. Kocharovsky, and N. Yu. Peskov
- Subjects
Physics ,Nuclear and High Energy Physics ,Silicon ,Physics::Instrumentation and Detectors ,business.industry ,chemistry.chemical_element ,Astronomy and Astrophysics ,Statistical and Nonlinear Physics ,Plane mirror ,Laser ,Electronic, Optical and Magnetic Materials ,law.invention ,Optics ,Semiconductor ,chemistry ,law ,Physics::Accelerator Physics ,Energy level ,Electrical and Electronic Engineering ,business ,Phase shift module ,Beam (structure) ,Microwave - Abstract
We study, both numerically and experimentally, a microwave commutator (phase shifter), whose active element comprises a metal plane mirror with a semiconductor plate on it. Phase shifting of the reflected microwave beam is attained by creating a conducting layer in the semiconductor by a laser with quantum energy approximately equal to the forbidden band width. Using a disk of high-purity silicon and a titatnium-sapphire pulsed laser, we study experimentally a 180° phase shifter operated with a Gaussian wave beam at a frequency of 30 GHz. Efficient phase shifting of the wave beam over a time of several nanoseconds is shown at a low power level.
- Published
- 2007
48. Efficiency Enhancement of Components Based on Talbot Effect
- Author
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G. G. Denisov, K. A. Fedorova, Yu. Yu. Danilov, S. V. Kuzikov, M. Yu. Shmelev, and M. E. Plotkin
- Subjects
Physics ,Radiation ,business.industry ,Scattering ,Physics::Optics ,Condensed Matter Physics ,Waveguide (optics) ,Light scattering ,Optics ,Talbot effect ,Classical electromagnetism ,Electrical and Electronic Engineering ,business ,Instrumentation ,Electrical impedance - Abstract
Two ways to increase efficiency of components based on Talbot effect are considered: optimization of waveguide wall impedance and corrections of waveguide cross-section. It is shown that for many cases undesired scattering losses can be made several times less than that for usual cases of infinite of zero impedance and rectangular waveguide cross-section.
- Published
- 2007
49. A high-speed quasi-optical wave phase switch based on the induced photoconductivity effect in silicon
- Author
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N. Yu. Peskov, G. G. Denisov, Vl. V. Kocharovskiĭ, M. Yu. Shmelev, Dmitry I. Sobolev, Sergey Kuzikov, A. N. Stepanov, Vladimir V. Parshin, and A. A. Vikharev
- Subjects
Materials science ,Physics and Astronomy (miscellaneous) ,Silicon ,Physics::Instrumentation and Detectors ,business.industry ,Photoconductivity ,Phase (waves) ,Physics::Optics ,chemistry.chemical_element ,Laser ,law.invention ,Optics ,Semiconductor ,chemistry ,law ,Optoelectronics ,Energy level ,business ,Microwave ,Beam (structure) - Abstract
A new microwave switch is proposed, in which the active element represents a metal reflector with a semiconductor plate on a mirror surface. The wave beam phase switching is ensured by a conducting layer formed in the semiconductor by laser radiation with quantum energy approximately equal to the bandgap width. Using a disk of high-purity silicon irradiated by a pulsed Ti:sapphire laser, a 180° phase switching in a 30-GHz wave beam has been studied. At a low microwave power level, the wave phase was effectively switched during a time on the order of several nanoseconds.
- Published
- 2007
50. [Untitled]
- Author
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A. V. Katalymov, M. G. Shmelev, and L. A. Tarasova
- Subjects
Trap (computing) ,Fuel Technology ,Waste management ,Geochemistry and Petrology ,Chemistry ,General Chemical Engineering ,Environmental engineering ,Energy Engineering and Power Technology ,Mineral resource classification - Published
- 2002
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