The exchange interaction of lanthanum and some lanthanides salts (neodymium, samarium, europium, gadolinium, terbium and dysprosium) with sodium salt of 2,4-dichlorophenoxyacetic acid (HL) in dimethylformamide medium produced lanthanum and lanthanide carboxylates. The compounds were studied by elemental and thermal analysis, infrared spectroscopy and X-ray structure analysis. It was found that the complexes form two isostructural series: [Ln2L6(DMF)3]center dot Solv (Ln = La, Nd, Sm, Eu) and [LnL3(H2O)2]center dot 2DMF center dot Solv (Ln = Gd, Tb, Dy). Both series have a one-dimensional polymer structure in which the central atoms are connected by bridging carboxylate anions. The crystal structures of the complexes have a branched network of noncovalent D-H...A and Cl...Cl interactions. An analysis of the photophysical properties of all compounds revealed a bright luminescence with a quantum yield up to 39.5 % and an excited state lifetime of 1330 mu s for the europium polymer enhanced by 2,4-dichlorophenoxyacetate ligands.

Compounds of three types, [LnL3(C2H5OH)] (Ln = Nd (I), Sm (II), Eu (III)), [LnL3(H2O)] (Ln = Gd (IV), Tb (V)), and [DyL2(NO3)(C2H5OH)2] (VI), were obtained by reactions of lanthanide nitrate with NaL (L– = 2,4-dichlorophenoxyacetate anion) in ethanol. The composition and structure of complexes I–VI were investigated by elemental and thermogravimetric analysis, IR spectroscopy, and X-ray diffraction (nos. 2311578 (I), 2311579 (II), 2311580 (III), 2311581 (IV), 2311582 (VI)). All compounds have a one-dimensional polymer structure in which metal atoms are connected by bridging carboxylate groups. The π–π interactions and intermolecular contacts between the chains give rise to a three-dimensional supramolecular structure.

Методами элементного и термогравиметрического анализа, ИК- и электронной спектроскопии, а также рентгеноструктурного анализа исследованы комплексы никеля(II) с 2,4-дихлорфеноксиацетилгидразоном пиридин-2-карбальдегида (HL). Установлено, что в зависимости от условий синтеза лиганды входят в комплекс в депротонированной или молекулярной форме, образуя соединения [NiL2]·2H2O (I) и [Ni(НL)L](NO3)·2H2O (II). Координационное окружение атома никеля(II) соответствует октаэдру, в котором лиганды проявляет тридентатную хелатирующую функцию. В соединении II реализутся межмолекулярные стэкинг-взаимодействия ароматических систем.

Синтезированы и исследованы методом РСА координационные соединения кобальта и никеля с азометиновым лигандом – продуктом конденсации 4-бензоил-3-метил-1-фенилпиразол-5-она и 2-аминофенола. Установлено, что ионы Со(II) в условиях реакции окисляются до Co(III) и образуют комплексы состава (Et3NH)[CoL2]×2H2O, в то время как ионы Ni(II) формируют соединение (Et3NH)(H3L)[NiL(HL)]×H2O×Solv. Анионная часть комплекса никеля представляет собой супрамолекулярный димер [Ni(L)(HL)]22-, сборка которого осуществляется посредством водородных связей. Комплексы изучены методом статической магнитной восприимчивости. Установлен диамагнетизм соединения Со, что подтверждает его окисление и свидетельствует о низкоспиновом состоянии иона металла. Обнаружены слабые ферромагнитные взаимодействия ионов Ni(II) через мостиковые водородные связи.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

The efficiency of the process of increasing the volume concentration of hydrogen in LiNbO3 crystals of congruent composition by heating in a humid atmosphere has been studied. It is shown that pretreatment of LiNbO3 crystals in adipic acid makes it possible to significantly increase the volume concentration of hydrogen in the sample during subsequent thermochemical treatment in moist air.

A cobalt(III) complex with pyridine-2-carbaldehyde 2,4-dichlorophenoxyacetylhydrazone (HL) is studied by elemental and thermogravimetric analyses, IR and electron spectroscopy, and single crystal XRD. It is found that regardless of the synthesis conditions cobalt(II) ions transform into cobalt(III), and two HL ligands are deprotonated in the complex and perform the tridentate chelating function. Dichloro substituted benzene rings are linked by intermolecular π–π interactions joining the monomeric complexes into a zigzag supramolecular chain.

Методами элементного и термогравиметрического анализа, ИК- и электронной спектроскопии, а также рентгеноструктурного анализа исследован комплекс кобальта(III) с 2,4-дихлорфеноксиацетилгидразоном пиридин-2-карбальдегида (HL). Установлено, что вне зависимости от условий синтеза ионы кобальта(II) переходят в кобальт(III), а два лиганда HL входят в состав комплекса в депротонированной форме и реализуют тридентатную хелатирующую функцию. Дихлорзамещенные бензольные кольца связаны межмолекулярными π-π взаимодействиями, объединяя мономерные комплексы в зиг-загообразную супрамолекулярную цепь.

In this study, we investigated the effect of terbium ions (Tb3+) on the subphases of the limiting area of the molecule for the complex compound (CC) TbL3∙bipy (where HL is 3-methyl-1-phenyl-4-stearoylpyrazol-5-one and bipy is 2,2′-bipyridine). We examined the Langmuir monolayer and the change in the luminescence properties of TbL3∙bipy-based Langmuir-Blodgett films (LBFs). The analysis of the compression isotherms, infrared, and luminescence spectra of TbL3∙bipy LBFs was performed by varying the concentration of Tb3+ in the subphases. Our results demonstrate the partial dissociation of the CC at concentrations of C(Tb3+) < 5 × 10−4 M.

Обобщены актуальные направления исследований в области металл-органических координационных полимеров (МОКП), проводимых в научных организациях и университетах России в последние 5—10 лет. Обзор охватывает вопросы дизайна, синтеза, топологического описания и прогнозирования свойств МОКП, разработки способов их химического конструирования и модификации, изучения современными физико-химическими методами, создания функциональных материалов на основе пористых каркасов (гетерогенных катализаторов, высокоэффективных и высокоселективных сорбентов нового поколения, проводящих материалов, систем для адресной доставки лекарств).

Current research fields of metal-organic frameworks (MOFs), which are being developed in the last 5-10 years by Russian scientific institutions and universities, are generalized. The review encompasses the design, synthesis, topological description, and prediction of MOF properties, the development of methods for their chemical engineering and modification, their investigation by modern physicochemical techniques, and the creation of functional materials based on porous frameworks (heterogeneous catalysts, highly efficient and highly selective sorbents of the new generation, conducting materials, systems for the target drug delivery).

The synthesis of oxovanadium(IV) complex with 1-hydroxyethane-1,1-diphosphonic acid (H4EDP) anion and bis(2-pyridyl-1,2,4-triazol-3-yl)methane (H2L) is described. The reaction of VOSO4 with H4EDP and H2L followed by neutralization of the reaction mixture with Et3N gives the trinuclear complex [(VO)4(H2L)2(EDP)2(H2O)2]·4H2O (I), which was studied by IR and ESR spectroscopy. The molecular and crystal structures of complex I were determined by X-ray diffraction (CIF file CCDC no. 2022772).

The reaction of ZnSO4·7Н2О with 1,2-bis(2-pyridyl-1,2,4-triazol-3-yl)ethane (Н2L) and 1‑hydroxyethane-1,1-diphosphonic acid (H4EDP) in an aqueous medium affords complex {[Zn2(H2L)(H2EDP)2(H2O)2]·2H2O}n, which is studied by elemental analysis and IR spectroscopy. The structure of the complex is determined by X-ray diffraction analysis (CIF file CCDC no. 2043698). The complex has the 1D polymeric structure and represents a zigzag chain in which two zinc(II) cations are joined by two bis(phosphonate) anions into the centrosymmetric binuclear fragments linked by the bridging bis(triazolyl)ethane molecules. The zinc(II) cation additionally coordinates the water molecule and exists in the distorted octahedral coordination environment. The luminescence spectrum of the complex exhibits a broad emission band with a maximum at 408 nm and a quantum yield of 4%.

Using the results of studying the electrical conductivity in the temperature range ~295–460 K and the IR absorption spectra of a series of LiNbO3:Mg crystals, it is shown that an increase in the Mg content leads to sharp decrease in the H+ ion mobility during their displacement along the polar direction. This effect is observed most clearly in LiNbO3:Mg crystals with high (superthreshold) impurity content.

Using the results of studying the electrical conductivity in the temperature range of ~ 295-460 K and the IR absorption spectra of a series of LiNbO3: Mg crystals, it is shown that as the Mg content in the sample increases, the mobility of H+ ions sharply decreases when moving along the polar direction. This effect is most clearly manifested in the samples of LiNbO3: Mg crystals with a high (above threshold value) impurity content.

A nine new Zn(II) complex were synthesized based on a new Salen-type tetradentate N2O2 ligands derived from 1-phenyl-3-methyl-4-formyl-5-pyrazolone. Complexes have been characterized by single-crystal X-ray diffraction, ESI-mass spectroscopy, elemental analysis, IR spectroscopy and thermal gravimetric analysis. UV–vis, emission and electrochemical studies indicated that changes of the electronic states of the diamine moieties are main parameter that influences the absorption and the emission color of the investigated zinc(II) complexes.

New coordination zinc compounds based on 3-methyl-4-formyl-1-phenylpyrazol-5-one acylhydrazones [Zn(L)(CH3COO)Solv] (Solv is H2O (I), Py (II)) are synthesized in order to search for new luminophores demonstrating efficient photoluminescence in the visible range. Complexes I and II are characterized by elemental and thermogravimetric analyses, mass spectrometry, and UV and IR spectroscopy. The structures of two complexes [Zn(L5)(CH3COO)H2O] and [ZnL4(CH3COO)Py] are determined by X-ray structure analysis (CIF files CCDC nos. 1958400 and 1958401, respectively). Complexes I and II demonstrate luminescence in the visible range with a maximum at 414–536 nm and a quantum yield of 9.5–64% depending on the nature of the acyl fragment.