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The presence in the modern Ossetian language of a functional-semantic field of aspectuality (hereinafter referred to as the FSF) with a polycentric core (grammatical category of type and grammatical category of polytemporal multiplicity) distinguishes it from closely related Iranian languages for which the grammatical expression of aspectual meanings is not relevant and noticeably brings it closer to the East Slavic, primarily with the Russian language, in which the expression of the specific meaning is mandatory for any verb. Meanwhile, the results of scientific research on this issue from the standpoint of comparative (Russian-Ossetian) and general aspectology achievements have not been practically introduced into the scientific use of modern Ossetian studies for the last decades, have not become the property of methodological and didactic manuals to help practical teachers, which, in our opinion, underlines the relevance of the research undertaken within the framework of this article. The genre of the article is somewhat unusual: it combines aspects of scientific coverage of the topic of the device of the core and periphery in the FSF of the aspectuality of the modern Ossetian language, the features of their interaction in comparison with the situation in the FSF of aspectuality in modern Russian, brief information about the landmark stages of the development of this problem, individual methodological recommendations and specific didactic proposals to help teachers-practitioners working with an Ossetian-speaking audience with both Russian and Ossetian language of instruction. The desire of the author of the article to “immerse” Ossetian scientists, practical teachers, philology students studying in the areas of dual qualification “Teacher of the native language. The teacher of the Russian language”, explains the bibliography of the question, which is greater than is customary in such publications, that in the situation of the lack of educational and methodological literature on this topic should be considered a plus rather than a flaw, as well as a detailed description of the conceptual (terminological) apparatus used in modern aspectology. All the fundamental differences in the organization of the core of aspectuality in the modern Ossetian language in comparison with Russian are highlighted on specific linguistic facts, as well as the most debatable aspects of the topic.

A series of D-π-A, D-π-D'-π-A, D-π-A'-π-A nonlinear optical chromophores with vinylene π-electron bridges or bridges with π-deficient/π-excessive heterocyclic moieties along with the corresponding precursors D-vinylene, D-π-D', D'-π-A, D-π-A' and A'-π-A are synthesized and studied both experimentally and computationally. The effect of the heterocycle in the π-electron bridge on the oxidation/reduction potentials and the energy gap (ΔEel ) is investigated in detail. The properties of the D-π-A'(D')-π-A chromophores are shown to correlate with those of building blocks: the oxidation potential is determined by the D-vinylene, and the reduction potential is determined by A'(D')-π-A truncated compounds. The contribution of the acceptor to the oxidation potential of chromophores in comparison with those of the precursors was estimated and analyzed in terms of electronic communication between the end groups. A good correlation between the ΔEel and the chromophores' first hyperpolarizability is revealed.

The key intermediate palladacycles (mono-, bi-, and tetranuclear) with phosphonate, acetate, and other counterions in C(sp2)–H phosphonation are analyzed in terms of their redox properties, mutual ...

Two chromophores with π-deficient quinoxaline (Q) core in the π-electron bridge together with dibutylaniline (DBA) donor moiety and tricyanofuranyl (TCF) or dicyanovinyl (DCV) acceptor moieties have been synthesized to investigate their macroscopic nonlinear optical (NLO) activity in guest-host materials. A distinctive feature of the 7-DBA-VQPhV-TCF chromophore is predominance of negative solvatochromism over the positive one, which is quite rarely met for the chromophores manifesting inverse solvatochromic behavior as well as the blue shift of the absorption maximum compared to the chromophore FTC with divinylthiophene π-bridge. Introduction of quinoxaline moiety in the conjugated bridge promotes the increase of thermal stability: Td of both compounds is higher than 225 °C. Density functional theory was used to calculate the chromophores first hyperpolarizability (β). Quadratic NLO response characterized by d33 coefficient was measured by SHG technique for thin guest-host polymer films. The influence of chromophore content on the NLO coefficient of 7-DBA-VQPhV-TCF/PMMA film has been investigated and the d33 value of this film reaches 108 pm/V at 25 wt% load. The poled film 7-DBA-VQPh-DCV/PMMA shows twice smaller d33 values (30 pm/V) at the same chromophore load (20 wt%).

Two novel chromophores with dibutylaniline donor moiety, 3,7-(di)vinylquinoxalinone π-electron bridge and tricyanofuranyl or dicyanovinyl acceptor moieties are synthesized and their properties were systematically investigated. Atomistic modeling of PMMA-based composites with the developed chromophores as guests is performed and nonlinear optical activity is studied for the first time. Atomistic modeling performed in the amorphous cell has shown that chromophore content 20 wt% may be considered most favorable for achievement of optimal d33 values for 7-DBA-VQonV-TCF/PMMA material. Various non-covalent interactions both between chromophores and polymer matrix and chromophores inter se were revealed in the course of modeling; these interactions could contribute to the relaxation stability of orientational order and thus quadratic NLO response. Composite material 7-DBA-VQonV-TCF/PMMA is characterized by nonlinear-optical coefficient, d33, values of 97, 111 and 47 pm/V at chromophore content of 10, 20 and 30 wt%, respectively. Thus chromophore content 20 wt% provides maximal value of NLO coefficient, what is in agreement with the obtained theoretical data. The d33 value for 7-DBA-VQonV-DCV/PMMA is 2.5 times smaller than that for 7-DBA-VQonV-TCF/PMMA at the same chromophore load (20 wt%).

This paper elucidates the redox properties and reactivity of a number of cyclometalated nickel(II) complexes in oxidation processes. Original and robust procedures for the synthesis of nickelacycles with two cyclometalated moieties and halogenated nickelacycles were developed. The complexes were studied by means of electrochemical, ESR, DFT, and single-crystal XRD methods. Notable features of the nickelacycles are unusually low oxidation potentials. Upon electrochemical oxidation the complexes produce carbon–carbon and carbon–heteroatom coupled products, the ratio of which can be tuned by the conditions applied.

For the first time the nonlinear optical (NLO) activity of indolizine-based push-pull chromophores with different acceptor moieties was studied and compared. All the chromophores demonstrate strong absorption band in the visible (orange-red) part of the spectrum, with e of ca. 105 L∙cm−1∙M−1 notably dependent on medium polarity. Replacement of Ph-TCF acceptor by Hex-TCP one results in twofold increase of the first hyperpolarizability value. Energy gaps estimated by electrochemical methods decrease in the series ΔE1a,b>ΔE3a,b>ΔE2a,b for compounds with Ph-TCF, DCM and Hex-TCP acceptors, respectively, good agreement with DFT estimations is obtained. The nonlinear optical coefficient for poled PMMA-based films, containing 20 wt% of isomeric indolizine chromophores with weaker dicyanomethylene (DCM) acceptor and with π- bridge expanded by isophorone moiety, achieves 36 pm/V, thus exceeding those for materials containing chromophores with stronger Ph-TCF or Hex-TCP acceptors and with short vinylene π-bridge.

Four chromophores belonging to a new class of push-pull chromophores with divinylphenylquinoxaline moieties have been designed and synthesized. The structure-property relationship was systematically investigated; the effect of the conformation on the value of chromophores first hyperpolarizability is found to be inessential. Quinoxaline-based chromophore with TCF acceptor and 7-dimethylanilinovinyl moiety displays the combination of favorable characteristics: the high value of the first hyperpolarizability, the small HOMO-LUMO energy gap, the blue shift of the absorption maximum relative to the chromophores with other divinylhetaryl or polyene π-bridges and ultrahigh thermal stability. This chromophore may be considered as a perfect candidate for the development of effective electro-optic materials.

Two series of isomeric indolizine-based chromophores with isophorone rings as a π-bridge have been synthesized and systematically investigated. The chromophores have a high thermal stability: the decomposition temperature is above 238 °C. For isomers with 1-methyl-2-phenylindolizin-3-yl (MPI-3) donor group higher values of β are predicted in comparison with those having 3-methyl-2-phenylindolizin-1-yl (MPI-1) donor group. This is in good agreement with the experimental and theoretical values of the HOMO-LUMO energy gap. Indolizine-based chromophores with barbituric acceptor and isophorone moieties in the π-bridge demonstrate the combination of good characteristics.

To further explore the potential application of the indolizine donor group in nonlinear optical (NLO) chromophores, we have designed and synthesized new push-pull chromophores (MPI-1)-V-TCF and (MPI-3)-V-TCF, having isomeric 3(1)-methyl-2-phenylindolizin-1(3)-yl (MPI-1(3)) electron donor and TCF acceptor, and compared them with dimethyl aniline (DMA) analogues. The Uv-Vis (linear optical) properties and solvatochromic behavior were also investigated; theoretical predictions of molecular NLO characteristics were done on the basis of the DFT calculations. The indolizine-based chromophores have high thermal stability: the decomposition temperature is 348 °C for (MPI-1)-V-TCF and 343 °C for the (MPI-3)-V-TCF, which is by 10–15 °C higher than that for the chromophore DMA-V-TCF. An important role is played by the bulky phenyl group, which prevents the aggregation of chromophores in guest-host doped polymer films. In NLO activities, the doped (MPI-1)-V-TCF/PMMA and (MPI-3)-V-TCF/PMMA films display the NLO coefficient, d33, values of 40 and 42 pm/V, correspondingly, at the chromophore load of 20 wt%.

The effect of rotational isomerism on the values of first hyperpolarizability is studied by the example of two chromophores 7-DMA-VQV-TCP and 3-DMA-VQ on V-TCP with quinoxaline and quinoxalinone moieties in the π-electron bridge. At the isomers formation the rotations about three single bonds are considered, thus providing eight possible conformers for each chromophore. The analysis of the results of DFT calculations demonstrates the presence of one lowest-energy conformer characterized by dominating probability for each chromophore. The calculations show that for both chromophores all rotational isomers are characterized by the first hyperpolarizability values rather close (within 8% and 11%) to statistically averaged ones.

Chromophores with charged heterocyclic acceptor moiety in combination with divinylquinoxaline conjugated π-bridge show a significant solvatochromic shift, small energy gap value (determined by various methods), and large values of the first hyperpolarizability estimated by DFT. A quinoxaline-based chromophore with an indolium acceptor exhibits an outstanding solvatochromic shift (0.38 eV), probably a record one for D-π-A chromophores with a dialkyl aniline donor moiety. A good correlation between the above characteristics and the calculated NBO π-charge on the aniline nitrogen atom has been found. A change in the trend by opposite one in the characteristics in the series of quinolinium /benzothiazolium/ indolium chromophores is exhibited when passing from gas to solvent.

Novel D-π-A chromophores with quinoxaline/quinoxalinone core in the π-conjugated bridge and various bulky groups in the acceptor moiety have been synthesized and systematically investigated at molecular level by UV–Vis spectroscopy, DFT calculations, electrochemical and TGA-DSC methods as well as at materials level by the example of PMMA-based composite polymer materials doped with different chromophore contents using molecular modeling and SHG technique. Chromophores exhibit positive dioxane/chloroform solvatochromic shift of ca. 50 nm, high values of first hyperpolarizability and dipole moment, small energy gap and good thermal stability. Tolyl and cyclohexylphenyl substituents unlike phenyl can be treated as most effective isolating groups, preventing chromophore pronounced aggregation even at 30 wt% content. Femtosecond nonlinear optical (NLO) activity was studied for poled thin guest-host polymer films with various chromophore weight content. Film DBA-VQPhV-TCFPhCy(25 wt%)/PMMA with bulky cyclohexylphenyl groups in chromophore acceptor shows maximal NLO coefficient, d33, values among the studied materials (37 pm/V) as well as good long-term stability of NLO response together with excellent chromophore thermal stability (Td = 256 °C). Composite materials doped with quinoxaline chromophores are photostable with respect to laser pulses with peak intensities up to 11 GW/cm2.

The molecular systems, modeling composite materials, are formed by the epoxy-amine oligomers with covalently bound chromophore-containing dendritic fragments (EAD) as a host and additional azo-chromophores as guests. The relationship between the structure and quadratic nonlinear optical characteristics of the model systems is established by atomistic modeling and quantum chemistry. The effect of the chain length of the model systems and the choice of the dendron structure, in particular, the length of the groups tethering chromophores to the branching center, on the values of first hyperpolarizability is studied. Molecular dynamics, performed for the model systems at various temperatures, reveals chromophores local mobility at temperature close to 130 °C; the calculations being fulfilled with the force field MMFF94s modified in terms of the ESP partial charges estimate at B3LYP/6-31G(d) level.

New class of nonlinear optical chromophores with donors containing indolizine moiety is proposed. Dipole moment and first hyperpolarizability values of the chromophores, which are analogs of FTC, CLD and OLD chromophores, containing 1-methyl-2-phenylindolizin-3-yl (MPI-3) or 3-methyl-2-phenylindolizin-1-yl (MPI-1) donors (instead of diethylaminophenyl), 3-cyano-2-dicyanomethylene-5,5-dimethyl-1,5-dihydrofuran-4-yl (TCF) acceptor, and 2,5-divinylthiophene, octatetraene and 2,2′-divinylbithiophene π-electron bridge, are calculated by DFT technique. Chromophores with named donors and acceptors and 3,7-divinylquinoxalin-2-one π-electron bridge are also studied. In most cases higher values of first hyperpolarizability were obtained for chromophores with MPI-3 donor, this being in accordance with the electron density distribution in these fragments. The change of dimethylaniline donor fragment for indolizine one results in the growth of the first hyperpolarizability values. This observation holds also for chromophores with divinylquinoxalinone π-electron bridge, in which higher values of first hyperpolarizability are obtained when the donor moiety is connected through vinylene group at position 3 rather than at position 7 of the quinoxalinone system.

New class of nonlinear-optical (NLO) chromophores is proposed, containing quinoxalin-2-one moiety in π-electron bridge. The chromophores electric characteristics (dipole moments and molecular polarizabilities) are calculated in the framework of the DFT technique, and structure – property relationship is established. The chromophores with donor bound in position 3 to quinoxalin-2-one one through vinyl group demonstrate the greatest NLO characteristics among the molecular systems under study. The calculated values of the first hyperpolarizability for the chromophores with 3,7-divinylquinoxalin-2-one π-electron bridge and TCF and TCP acceptor fragments exceed the corresponding values of the majority of the known world analogues.

A series of substituents of various types in chromophore donor moiety in ortho- and meta-positions relative to divinylquinoxaline π-electron bridge was examined for isolating ability, preventing the dipole chromophores antiparallel detrimental aggregation in polymer matrix. The study was performed by molecular modeling of PMMA-based composite polymer materials with different content of pristine chromophore with dibutylaniline donor, divinylquinoxaline π-electron bridge and tricyanofuran acceptor (I) in the range from 10 wt% to 30 wt%, and of composite polymer materials with 30 wt% load of chromophores with various isolating groups of aryl, alkyl and mixed nature in donor moiety. The effect of the substituents in donor groups on the molecular nonlinear-optical (NLO) characteristics of chromophores – first hyperpolarizability – was estimated by quantum-chemical calculations at DFT level with M06-2X density functional. Introduction of isolating group in meta-position of donor is shown to lead to a strong decrease of the first hyperpolarizability of a chromophore compared to that of pristine chromophore. Joint consideration of results of molecular modeling and quantum-chemical calculations allows one to nominate o-ethyl, o-benzyloxyhexyloxy and m-methoxy-o-phenyl groups to be the best isolating ones.

A series of diverse binuclear and mononuclear cyclometalated palladium(II) complexes of different structure was investigated by electrochemical techniques combined with density functional theory (DFT) calculations. The studies including cyclic and differential pulse voltammetry, X-ray structure analysis and quantum chemical calculations revealed a regularity of the complexes oxidation potential on the metal–metal distance in the complexes: the larger Pd–Pd distance, the higher oxidation potentials. The reduction potentials feature unusually high negative values while no correlation depending on the structure could be observed. These results are in a good agreement with the electron density distribution in the complexes. Additionally, ESR data obtained for the complexes upon oxidation is reported.

The task of shaping a civil nation, requires the support of the University pedagogic community, to develop innovative technologies that would allow for an educational effect on young people’s personalities, taking into account the specificity of the three sides of their identity – Russian (civil and civilizational), ethnic (ethnic-confessional), and regional. In the traditional North Caucasian societies where the family network and the religion make up for the personality basics that will be maintained through life, the ethnic (ethnic-confessional) identity presents a crucial factor for socialization.The level of the regional identity – a second part of the civil identity – reveals different degrees of development in different parts of Russia. In the North Caucasus many Russians, including ethnic Russians, as well members of Diasporas identify themselves as North Caucasians regardless of their specific ethnic and confessional group. From here we could state that, the regional factor of the civil identity, along with the ethnic-confessional “profile” is an important condition for shaping a common Russian identity.A contemporary variant of the Russian identity does not act as a fully valid integrating origin for developing a common Russian identity. The multicultural Russian society needs a deeper level of integration involving not just supra-ethnic and supra-confessional nature of the respective identity, but also socio-cultural unity based on common values. Such unity may only be due to civilizational identity that implies a deep penetration into the area of national cultures, into the system of vitally important values that lie within the “responsibility zone” of the ethnic and the confessional identities.