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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.

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.

A new methacrylic monomer, 3,5-bis[2-(N-ethylanilino)ethoxy]benzyl methacrylate (MBA), has been synthesized. Methacrylic copolymers with different content of bi-chromophore fragments in the side chain were obtained by radical copolymerization of methyl methacrylate and MBA, followed by azo-functionalization reaction. The composition of the obtained copolymers was established, and their thermal properties were determined. Thin films of synthesized copolymers were prepared by spin-coating and the nonlinear optical characteristics of the obtained materials were investigated.

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.

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.

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.

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.

The fabrication of hybrid materials combining the physicochemical properties of various classes is a complicated but promising trend for the development of the modern science. The formation of new hybrid cluster cations [Mo3Pd(C60)S4Cl3(R2Bipy)3]+ and [{Mo3PdS4Cl3(R2Bipy)3}2(C60)]2+ (Bipy is 2,2-bipyridine) containing fullerene C60 coordinated to the palladium atom by the reaction of [Mo3S4Cl3(R2Bipy)3]PF6 with Pd2(Dba)3 (Dba is dibenzylideneacetone) and C60 is shown by a complex of physicochemical methods. The reaction products are studied by IR and NMR (1H, 31Р, and C–H correlations) spectroscopy and mass spectrometry. The quantum-chemical calculations are performed by the DFT method for the correct interpretation of the spectroscopic data and elucidation of the electronic structures of the fullerene-containing compounds.

The reaction of [Mo3S4(Tu)8(H2O)]Cl4·4H2O (Tu is thiourea) with (PhCH2CH2)2-PCH2CH2SeC5H11) (PSe) followed by purification on a chromatographic column packed with silica gel using a saturated solution of KPF6 in acetone as an eluent results in the formation of [Mo3S4Cl3(PSe)3]PF6 (I) in a yield of 44%. Compound I is characterized by X-ray diffraction analysis, 1H, 31P{1H}, and 77Se NMR spectroscopy, IR spectroscopy, UV-Vis spectroscopy, cyclic voltammetry, and electrospray ionization mass spectrometry. Several species differed in the coordination mode of three PSe ligands, which can bind to molybdenum via one (phosphorus) or two (phosphorus and selenium) donor atoms, are formed in a solution of compound I at room temperature. This behavior is not observed for the compounds similar in structure with PS ligands of an analogous type. Complex I demonstrates a higher catalytic activity than its analogue with the PS ligand in the reduction of nitrobenzene to aniline under the action of diphenylsilane.

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)).

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.

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)).

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.

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.

In this article, the model including cathode spot process and deuterium desorption process on zirconium deuterium cathode is developed. Five kinds of particle fluxes on cathode surface and three mechanisms affecting deuterium diffusion in cathode are considered. The model not only describes the deformation of cathode metal, but also describes the variation of deuterium concentration with time. On pure zirconium cathode, the mean charge state is larger but on zirconium deuterium cathode, the total ion number density is larger since there are additional deuterium ions, and simulation results show the discharge currents are very close on the two cathodes, the energy flux density on ZrD0.66 cathode is larger so cathode spot crater develops faster on ZrD0.66 cathode. Ablation rates caused by different mechanisms are calculated and the results show in cathode spot development process, mass loss caused by evaporation is ignored, most of the liquid metal will resolidify on cathode surface, and droplets are the main reason for cathode ablation. The ablation rates due to the ejection of droplets are close to experimental results. The ratios of deuterium ion from different mechanisms in this process are also calculated and it is 93.5% in simulation. Simulation results are in agreement with the other researchers’ works.

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.

The specific features of burning in air the cylindrical samples obtained from the bulk density of magnesium powder are studied. We record a significant content of magnesium nitride in the reaction’s products as opposed to burning individual magnesium particles in air, which mainly results in the formation of magnesium oxide. The sample’s increased diameter leads to a significant decrease of the degree of magnesium’s transformation. It is shown that introduction of 1–15% of finely dispersed iron oxide powder leads to an increase in the degree of the chemical transformation of magnesium. The transformation is a two-stage process at the characteristic temperatures of 650 and 1050°С. The mechanism of the action of the iron oxide additive based on the multiple repetition of the reactions of substituting iron by magnesium in the oxide with the formation of free iron and its oxidation with the formation of a new portion of iron oxide is proposed.

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.

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.

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.

Heterometallic carboxylate complexes are of paramount interest in pure and applied coordination chemistry. Despite that plurality of such type compounds have been published to date, synthetic aspects of their chemistry often remain in the shadow of intriguing physical properties manifesting by these species. Present review summarizes reliable data on direct synthesis of low nuclearity molecular compounds as well as coordination polymers on their base with carboxylate-bridged {M2Mg} (M = Co2+, Ni2+, Cd2+), {M2Li2} (M = Co2+, Ni2+, Zn2+, VO2+), {M2Ln2} and {M2Ln} (M = Cu2+, Zn2+, Co2+) metal cores. Structural features and stabilization factors are considered and principal outcomes are confirmed by quantum-chemical calculations. Particular attention is paid to consideration of ligand-exchange reactions that allow controllable modification of heterometallic metal core under mild conditions giving diverse molecular complexes with modified ligand environment or Metal-Organic Frameworks with permanent porosity.

The preparation of 2D stacked layers combining flakes of different nature gives rise to countless numbers of heterostructures where new band alignments, defined at the interfaces, control the electronic properties of the system. Among the large family of 2D/2D heterostructures, the one formed by the combination of the most common semiconducting transition metal dichalcogenides, WS2 /MoS2 , has awakened great interest owing to its photovoltaic and photoelectrochemical properties. Solution as well as dry physical methods have been developed to optimize the synthesis of these heterostructures. Here, a suspension of negatively charged MoS2 flakes is mixed with a methanolic solution of a cationic W3 S4 -core cluster, giving rise to a homogeneous distribution of the clusters over the layers. In a second step, a calcination of this molecular/2D heterostructure under N2 leads to the formation of clean WS2 /MoS2 heterostructures, where the photoluminescence of both counterparts is quenched, proving an efficient interlayer coupling. Thus, this chemical method combines the advantages of a solution approach (simple, scalable, and low-cost) with the good quality interfaces reached by using more complicated traditional physical methods.

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).

Using amplified femtosecond pulses at a wavelength of 1028 nm, the second harmonic is generated at a wavelength of 514 nm by composite polymer films containing D-π-A (push–pull) chromophores with quadratic optical nonlinearity. It is shown that these films are photostable with respect to laser pulses having peak intensities of up to 11.6 GW/cm2. The effective generation of the second harmonic is observed in a wide range of pump beam incidence angles (20°–80°) with a maximum in the vicinity of 60°.

Elimination of the chloride ion from the [(PPh3)AuCl] complex using silver triflate (AgOTf) in the presence of 2,2′-bipyridine R2bpy (the Au : R2bpy molar ratio is 2 : 1) in dichloromethane at room temperature leads to dinuclear gold(I) complexes [(PPh3Au)2(μ-R2bpy)](OTf)2 (R2bpy = bpy (1), dbbpy (2), CH3Obpy (3), 3-CO2CH3bpy (4), 4-CO2CH3bpy (5)) in high yields. The crystal structures for all compounds were determined using X-ray diffraction analysis. In all structures, gold ions are in a typical linear environment, and the bipyridine molecule is twisted, which allows intramolecular aurophilic interactions. Relatively short Au(I)⋯Au(I) contacts (3.1262 (2)–3.400 (1) A) are found in structures 3–5. DFT calculations show the presence of bond critical points (3, −1) for aurophilic interactions in these structures. In structures 1 and 2, the Au(I)⋯Au(I) distances are noticeably larger and equal to 4.479 (1) and 4.589 (1) A respectively; there are no bond critical points (3, −1) for aurophilic interactions. All complexes show photoluminescence in solid state at room temperature when excited at 300 nm in a wide spectral range: from blue or blue-green emission (400–460 nm) for 1–4 to orange emission (580 mn) for 5. The lifetimes of the excited state are in the microsecond range which is characteristic of phosphorescence. TD-DFT calculations reveal that electronic transitions of different nature are responsible for the photoluminescence of these compounds.

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.

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.

The combustion regimes were studied and the oxygen index for the bulk-density magnesium powder with a particle size of ~80 μm placed in a paper cup was determined in nitrogen–oxygen and argon–oxygen mixtures at pressures from 0.3 to 1 atm. It was shown that at a constant pressure of the mixture, there was a minimum concentration of oxygen at which sustained propagation of the combustion front was possible. The boundaries of the region of stable combustion of such a system in the pressure–oxygen concentration coordinates were determined. It was shown that, depending on the oxygen concentration, two combustion modes were possible: one-step mode far from the combustion limit and spin mode at the combustion limit. As the pressure or oxygen concentration in the mixture increased, the characteristic spin rotation time decreased and the propagation of the combustion front over the sample passed into a layer-by-layer mode. The dependence of the combustion front propagation velocity on the sample near the combustion limit on the mixture pressure and the oxygen concentration in its composition was determined.

Catalytic hydrogenation of aromatic hydrocarbons is one of the most important reactions in industry. The use of copper as a modifier of silica is beneficial both from an economic point of view and from the point of view of ease of modification. The catalytic properties of a mesoporous structured material modified by copper (Cu/MCM) and a mesoporous structured material (MCM) doped with dysprosium and modified copper (Dy-Cu/MCM) synthesized by the template method were studied in xylene hydrogenation reactions. The textural characteristics of the catalysts obtained were studied by low-temperature nitrogen adsorption-desorption, ICP, XRF, XRD, SEM, TEM. To determine the specific surface area, the BET model was used with a relative partial pressure P/P0 0.05-0.3. The total pore volume and size distribution of meso- and macroporous was calculated from the desorption curve using the BJH model. With the help of the ICP-method, the metals were also quantitatively determined using the absolute calibration method. For the analysis of microporous, the DFT density functional method was used. The study of the kinetics of hydrogenation of o, m, p-xylenes was carried out in the temperature range 130-170 °C and a hydrogen pressure of 3 atm. The kinetics of gas-phase hydrogenation reactions was studied in a static mode using the method of gas chromatography, on the original setup, which allows on-line analysis of the reaction mixture. The xylene conversions on Cu/MCM and Dy-Cu/MCM catalysts are calculated at various reaction temperatures.

The signal of the ultrafast optical Kerr effect (OKE) in liquids, including toluene C7H8, nitrobenzene C6H5NO2, and acetonitrile C2H3N is analyzed. It is shown that considering the correlation between the orientational and librational responses allows us to determine the rise time of the orientational response associated with the inertial nature of molecular rotations over a time interval of 300–500 fs after the impact of a laser pulse, and to increase the accuracy of determining the form of the Raman spectral density function.

The catalytic activity of synthesized by the template method mesoporous silica doped with dysprosium and modified with nickel (Dy-Ni/MPS) in the hydrogenation of benzene, ethylbenzene and xylenes has been studied. The catalyst is characterized by various techniques such as TEM, SEM, BET, XRD, ICP, XRF analyses. It is shown that the presence of dysprosium in the MPS structure increases the activity of the catalyst. The catalytic activity of the catalyst (Dy-Ni/MPS) has been explored in hydrogenation reaction of benzene derivatives with excellent conversion (96–100%) at low pressure.

The possibility of providing an appreciable decrease in carbon monoxide concentrations in products due to the combustion of natural gas-air mixtures in infrared burners by installing a radiation gauze screen with a catalytic Pd-Ce/Al2O3 coating over the matrix is demonstrated. When permeable matrices with radiation gauze screens with and without catalytic coatings are used, the concentration of nitrogen oxides in combustion products was less than 20 ppm within a range of specific combustion powers from 20 to 100 W/cm2. The use of a screen with a catalytic coating provides record low CO concentrations in combustion products at a level of 3–5 ppm within a range of specific combustion powers from 30 to 60 W/cm2. The catalytic coating on the gauze screen that is developed retains its serviceability through multiple cycles of heating to temperatures of 1400 K.

Experiments on recording the ultrafast optical Kerr effect (OKE) in solution of europium(III) β‑diketonate complexes in toluene at a concentration of 10–2 mol/L showed that the total OKE signal is not a superposition of two contributions, one of which is related to the vibrational–rotational dynamics of toluene molecules, while the other is due to the vibrational–rotational dynamics of the europium(III) complexes. This immediately indicates that the europium(III) complexes essentially change the structure of liquid toluene, which is reflected in the character of an orientational response in picosecond range.

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.

Interest in the investigation of adsorption and thermodynamic characteristics of mesoporous silica gels is increasing due to a number of advantages of these materials, such as chemical inertness, developed specific surface area, high chemical and mechanical stability, low toxicity and biospecificity. All these prop- erties make them promising for use in medicine, as sorbents and carriers for catalysts of industrially impor- tant processes. The aim of this work was to synthesize mesoporous silicas modified with nickel and copper and to study their adsorption properties. The synthesis of mesoporous silicas and their modification with nickel and copper nanoparticles were developed. Moreover, textural characteristics of these materials were obtained. In addition, it was shown that the modification leads to a significant decrease in the specific surface area and pore volume. Likewise, the differential heat of adsorption (Ǭ1) and changes in standard differential molar entropies of adsorption ∆S1 ,с⁰ of test organic compounds with various types of intermolecular interactions were calculated using inverse gas chromatography. In conclusion, it is shown that modification MCM with nickel and copper nanoparticles increases dispersive interactions of organic compounds on this materials comparing to unmodified MCM. Analysis of compensatory thermodynamic dependencies has established that entropy is the determining thermodynamic parameter for adsorption of organic compounds on MCM, MCM (Ni) and MCM (Cu).

The paper analyzes a principal capability to transmute neptunium, the main component of transuranium radiowastes (TRW), in lead-cooled fast BREST-type reactor. High-energy neutron spectrum of the BREST-type fast reactor makes it possible either to eliminate neptunium in fission reactions or convert neptunium to plutonium with large fraction of 238Pu in radiative neutron capture reactions. According to the IAEA regulatory documents, plutonium containing above 80% 238Pu is regarded as an unsuitable material for manufacturing of nuclear explosive devices. Besides, good neutron-multiplying properties of 238Pu and 239Pu can prolong substantially the reactor core lifetime. Thus, introduction of neptunium into fresh fuel composition can eliminate the largest TRW fraction, strengthen regime of nuclear non-proliferation, produce some additional amount of thermal energy and prolong the reactor core lifetime.

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.

The effect of energy deposition on the composition of the outlet mixture was studied in a plasmachemical reactor with barrier discharge. The composition of the conversion products was analyzed using a gas chromatograph and a quadrupole mass spectrometer. The process mainly occurred by the thermal mechanism of chain initiation and propagation. At an energy input of 3.25 eV/molecule, the selectivity for the main reaction products was 11.56% for acetylene, 14.76% for ethylene, 30.51% for ethane, 16.84% for propylene, 15.01% for propane, and 7.02% for hydrogen.

Reaction of heterometallic cubane-type cluster complexes&mdash, [Mo3{Pd(dba)}S4Cl3(dbbpy)3]PF6, [Mo3{Pd(tu)}S4Cl3(dbbpy)3]Cl and [Mo3{Pd(dba)}S4(acac)3(py)3]PF6, where dba&mdash, dibenzylideneacetone, dbbpy&mdash, 4,4&prime, di-tert-butyl-2,2&prime, bipyridine, tu&mdash, thiourea, acac&mdash, acetylacetonate, py&mdash, pyridine, with white phosphorus (P4) in the presence of water leads to the formation of phosphorous acid H3PO3 as the major product. The crucial role of the Pd atom in the cluster core {Mo3PdS4} has been established in the hydrolytic activation of P4 molecule. The main intermediate of the process, the cluster complex [Mo3{PdP(OH)3}S4Cl3(dbbpy)3]+ with coordinated P(OH)3 molecule and phosphine PH3, have been detected by 31P NMR spectroscopy in the reaction mixture.

The reaction of (NBu4)2Bzmal (where Bzmal2&minus, is benzylmalonate dianion) with Co(OAc)2∙4H2O gives the [Co(Bzmal)(EtOH)(H2O)]n 2D-polymer (1). The addition of 2,2&prime, bipyridine (bpy) to the starting system results in the [Co(Bzmal)(bpy)2]&middot, H2O&middot, EtOH molecular complex (2). Their molecular and crystal structures were analyzed by single-crystal X-ray crystallography. An analysis of the static magnetic data supported by the SA-CASSCF/NEVPT2 calculations revealed the presence of easy-plane magnetic anisotropy in both complexes. The AC susceptibility data confirm that both complexes show a slow field-induced (HDC = 1000 Oe) magnetic relaxation behavior.

BACKGROUND: The efficacy and safety of benralizumab, an interleukin-5 receptor alpha-directed cytolytic monoclonal antibody, for the prevention of exacerbations in patients with moderate to very severe chronic obstructive pulmonary disease (COPD) are not known.METHODS: In the GALATHEA and TERRANOVA trials, we enrolled patients with COPD (at a ratio of approximately 2:1 on the basis of eosinophil count [≥220 per cubic millimeter vs. RESULTS: In GALATHEA, the estimates of the annualized exacerbation rate were 1.19 per year (95% confidence interval [CI], 1.04 to 1.36) in the 30-mg benralizumab group, 1.03 per year (95% CI, 0.90 to 1.19) in the 100-mg benralizumab group, and 1.24 per year (95% CI, 1.08 to 1.42) in the placebo group; the rate ratio as compared with placebo was 0.96 for 30 mg of benralizumab (P = 0.65) and 0.83 for 100 mg of benralizumab (P = 0.05). In TERRANOVA, the estimates of the annualized exacerbation rate for 10 mg, 30 mg, and 100 mg of benralizumab and for placebo were 0.99 per year (95% CI, 0.87 to 1.13), 1.21 per year (95% CI, 1.08 to 1.37), 1.09 per year (95% CI, 0.96 to 1.23), and 1.17 per year (95% CI, 1.04 to 1.32), respectively; the corresponding rate ratios were 0.85 (P = 0.06), 1.04 (P = 0.66), and 0.93 (P = 0.40). At 56 weeks, none of the annualized COPD exacerbation rate ratios for any dose of benralizumab as compared with placebo reached significance in either trial. Types and frequencies of adverse events were similar with benralizumab and placebo.CONCLUSIONS: Add-on benralizumab was not associated with a lower annualized rate of COPD exacerbations than placebo among patients with moderate to very severe COPD, a history of frequent moderate or severe exacerbations, and blood eosinophil counts of 220 per cubic millimeter or greater (Funded by AstraZeneca [GALATHEA and TERRANOVA] and Kyowa Hakko Kirin [GALATHEA]; GALATHEA and TERRANOVA ClinicalTrials.gov numbers, NCT02138916 and NCT02155660.).

A model is proposed for investigation of the ionization processes in a plasma jet emitted by a cathode spot cell of W-fuzz cathodes. It was shown that the introduction of helium atoms and the associated change in the morphology of the surface of the tungsten cathode leads to a significant change in the parameters of the arc plasma: a sharp decrease in the electron temperature and the mean charge state of tungsten ions.