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The authors continue to develop and delve deeper into their ideas on conceptual design. Previously we examined the role and significance of a conceptual design within the framework of the antinomy "singular-universal" or, more specifically, "project - science". In this article, we discuss issues related to the development of conceptual thinking necessary for conceptual design. It is demonstrated that conceptual design takes place on the basis of ideal models of objects or design techniques called constructs. The success of conceptual design depends on the ability to apply constructs (the "ownership" component in the competence approach). To successfully apply constructs, it is important to limit their possible number. This requires the conceptualization of the subject area. Practical techniques for conceptualizing the subject area and subsequent conceptual design are demonstrated.

The article discusses a methodology of conceptual design intended for students Architectural and Landscape Design students. The methodology combines analysis of interactions between design and research, which are opposite in many ways. Conceptual design is a connecting link between them. On the one hand, conceptual design is free from some limitations inherent in regulated design practice. On the other hand, conceptual design becomes a research hypothesis that requires proof. This point of view has been verified in the Master degree course.

The subject of the study is green city infrastructure. The content of the concept ‘green infrastructure’ is expounded, and the reasons why the term ‘green infrastructure’ is now mostly used. Special attention is paid to the structural properties of the green infrastructure, in particular to the main element that ensures its sustainability - the green framework. As a case in point, we considered the condition of the green infrastructure framework in the city of Ekaterinburg. Issues around the green infrastructure framework were identified and described regarding its structural properties. Long-term risks arising from the mismatch between the structural properties of the green infrastructure framework and the needs of city development are assessed. The novelty of the study lies in the fact that we used not only the traditional methods such as mapping, graphical analytic technique, and photo surveying, but also new modern approaches such as geo-referenced data, multispectral space images from which different indices are calculated, in particular combinations of images in different channels. The article shows how different indices can be applied and used to analyze green infrastructure. It is concluded that in a number of cases it is the use of geo-referenced data that allows obtaining unique information about the condition of the green infrastructure and the causes of long-term changes occurring in it. All the identified regularities are used to evaluate the design decisions laid down in the general plan of the city to forecast risks and create recommendations that contribute to the sustainable development of green infrastructure.

Dehydration is one of the main technological processes in the production of food and pharmaceutical products. Dehydration allows products to extend their shelf life, or is an intermediate step in product manufacturing. An important direction in improving the efficiency of production of agricultural products is to control the consumption of heat and electricity. It has been established that waste heat can be used as a free efficient source of low-potential energy for the drying process. This article discusses the benefits of using a heat pump for the drying processes of agricultural products. Heat pump drying can obtain high quality products at low energy costs. A comparative analysis of the convective drying method using a heat pump with other modern dehydration methods of agricultural products was carried out. It was revealed that convective drying with the use of a heat pump is the most advantageous method of dehydration of agricultural complex products.

The article considers issues in the development of the green infrastructure of Ekaterinburg, a large growing city. The green infrastructure is reviewed using the urban environment quality index, remote sensing data, and predictive methods. The conclusion is that Ekaterinburg does not have a well-formed green infrastructure: there are no pronounced cores and connections. An analysis of the Master Plan in relation to the development of the green infrastructure demonstrates that the green spaces lack linear elements, while the implementation of the concept that is being promoted by the city administration will exacerbate the problems associated with the city’s microclimate and available water resources.

The study explores the water and planting infrastructure framework of Yekaterinburg. Currently, this framework of Yekaterinburg is degrading due, first of all, to the utilitarian approach to the place and role of the river in the city historically established in the course of evolution of this Ural plant town. As a result, the Iset River as the main element of the water and planting infrastructure framework lost its most important function of communication due to the multiple barriers preventing access to water, circulation routes in the transverse direction relative to the river, and super-dense development in the river area. All these factors hinder the development of a modern water and planting infrastructure framework. The study reviews landscape and urban planning experiences in the construction of water and planting infrastructures and identifies requirements for developing a water and planting infrastructure framework and its role in urban development. We have also reviewed the modern-day concepts of water-and-planting infrastructure framework development proposed by the architectural community and the authorities. These are shown not to meet modern requirements for water-and-planting infrastructure frameworks. The authors propose their own system of requirements and demonstrate that the key element for the water-and-planting framework is the concept of riverine area, which should be delineated spatially and given a legal definition to ensure its status of protected area.

A series of heteroleptic bipyridine Pd(II) complexes based on 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-Bian) or 1,2-bis[(2,4,6-trimethylphenyl)imino]acenaphthene (tmp-Bian) were prepared. All complexes were fully characterized by spectrochemical methods, and their crystal structures were confirmed by X-ray diffraction analysis. The 72 h stability of heteroleptic bipyridine Pd(II) complexes with Bian ligands under physiological conditions was investigated using 1 H NMR spectroscopy. The anticancer activity of all complexes was assessed in a panel of cancer cell lines in comparison with uncoordinated ligands and clinically used drugs cisplatin and doxorubicin. The ability of the complexes to bind DNA was investigated using several methods, including EtBr replacement assay, density functional theory calculations, circular dichroism spectroscopy, DNA gel electrophoresis, and TUNEL assay. The electrochemical activity of all complexes and the uncoordinated ligands was studied using cyclic voltammetry, and reactive oxygen species production in cancer cells was investigated using confocal microscopy. Heteroleptic bipyridine Pd II -Bian complexes were cytotoxic in a low micromolar concentration range and showed some selectivity toward cancer cells in comparison with noncancerous MRC-5 lung fibroblasts.

A series of iridium complexes with bis(diisopropylphenyl)iminoacenaphtene (dpp-bian) ligands, [Ir(cod)(dpp-bian)Cl] ( 1 ), [Ir(cod)(NO)(dpp-bian)](BF 4 ) 2 ( 2 ) and [Ir(cod)(dpp-bian)](BF 4 ) ( 3 ), were prepared and characterized by spectroscopic techniques, elemental analysis, X-ray diffraction analysis and cyclic voltammetry (CV). The structures of 1 - 3 feature a square planar backbone consisting of two C = C π-bonds of 1,5-cyclooctadiene (cod) and two nitrogen atoms of dpp-bian supplemented with a chloride ion (for 1 ) or a NO group (for 2 ) to complete a square-pyramidal geometry. In the nitrosyl complex 2 , the Ir-N-O group has a bent geometry (the angle is 125°). The CV data for 1 and 3 show two reversible waves between 0 and -1.6 V (vs. Ag/AgCl). Reversible oxidation was also found at E 1/2 = 0.60 V for 1 . Magnetochemical measurements for 2 in a range from 1.77 to 300 K revealed an increase in the magnetic moment with increasing temperature up to 1.2 μ B (at 300 K). Nitrosyl complex 2 is unstable in solution and loses its NO group to yield [Ir(cod)(dpp-bian)](BF 4 ) ( 3 ). A paramagnetic complex, [Ir(cod)(dpp-bian)](BF 4 ) 2 ( 4 ), was also detected in the solution of 2 as a result of its decomposition. The EPR spectrum of 4 in CH 2 Cl 2 is described by the spin Hamiltonian Ĥ = gβHŜ with S = 1/2 and g xx = g yy = 2.393 and g zz = 1.88, which are characteristic of the low-spin 5d 7 -Ir(II) state. DFT calculations were carried out in order to rationalize the experimental results.

Self-assembly of (Bu 4 N) 4 [β-Mo 8 O 26 ], AgNO 3 , and 2-bis[(2,6-diisopropylphenyl)-imino]acenaphthene (dpp-bian) in DMF solution resulted in the (Bu 4 N) 2 [β-{Ag(dpp-bian)} 2 Mo 8 O 26 ] ( 1 ) complex. The complex was characterized by single crystal X-ray diffraction (SCXRD), X-ray powder diffraction (XRPD), diffuse reflectance (DR), infrared spectroscopy (IR), and elemental analysis. Comprehensive SCXRD studies of the crystal structure show the presence of Ag + in an uncommon coordination environment without a clear preference for Ag-N over Ag-O bonding. Quantum chemical calculations were performed to qualify the nature of the Ag-N/Ag-O interactions and to assign the electronic transitions observed in the UV-Vis absorption spectra. The electrochemical behavior of the complex combines POM and redox ligand signatures. Complex 1 demonstrates catalytic activity in the electrochemical reduction of CO 2 .

Hydrothermal reaction of a macrocyclic inorganic POM cavitand Li 17 (NH 4 ) 21 H 2 [P 8 W 48 O 184 ] with [Pt(H 2 O) 2 (OH) 4 ] results in coordination of up to six {Pt(H 2 O) x (OH) 4- x } fragments to the internal surface of the polyoxoanion. The product was isolated as K 22 (NH 4 ) 9 H 3 [{Pt(OH) 3 (H 2 O)} 6 P 8 W 48 O 184 ]·79H 2 O ( 1 ) and characterized by multiple techniques in the solid state (SCXRD, XRPD, XPS, FTIR, and TGA) and in solution (NMR, ESI-MS, and HPLC-ICP-AES). Electrochemical properties were studied both in solution and as components of the paste electrode. The complex shows electrocatalytic activity in water oxidation.

The reactions of CuX 2 (X = Cl, Br) with dipinodiazafluorenes yielded four new complexes [CuX 2 L 1 ] 2 (X = Cl ( 1 ), Br ( 2 ), L 1 = (1R,3R,8R,10R)-2,2,9,9-Tetramethyl-3,4,7,8,9,10-hexahydro-1H-1,3:8,10-dimethanocyclopenta [1,2-b:5,4-b']diquinolin-12(2H)-one) and [(CuX 2 ) 2 L 2 ]n (X = Cl ( 3 ), Br ( 4 ), L 2 = (1R,3R,8R,10R,1'R,3'R,8'R,10'R)-2,2,2',2',9,9,9',9'-Octamethyl-1,1',2,2',3,3',4,4',7,7',8,8',9,9',10,10'-hexadecahydro-1,3:1',3':8,10:8',10'-tetramethano-12,12'-bi(cyclopenta [1,2-b:5,4-b']diquinolinylidene). The complexes were characterized by IR and EPR spectroscopy, HR-ESI-MS and elemental analysis. The crystal structures of compounds 1 , 2 and 4 were determined by X-ray diffraction (XRD) analysis. Complexes 1 - 2 have a monomeric structure, while complex 4 has a polymeric structure due to additional coordinating N,N sites in L 2 . All complexes contain a binuclear fragment {Cu 2 (μ-X) 2×2 } (X = Cl, Br) in their structures. Each copper atom has a distorted square-pyramidal coordination environment formed by two nitrogen atoms and three halogen atoms. The Cu-N ax distance is elongated compared to Cu-N eq . The EPR spectra of compounds 1 - 4 in CH 3 CN confirm their paramagnetic nature due to the d 9 electronic configuration of the copper(II) ion. The magnetic properties of all compounds were studied by the method of static magnetic susceptibility. For complexes 1 and 2 , the effective magnetic moments are µ eff ≈ 1.87 and 1.83 µ B (per each Cu 2+ ion), respectively, in the temperature range 50-300 K, which are close to the theoretical spin value (1.73 µ B ). Ferromagnetic exchange interactions between Cu(II) ions inside {Cu 2 (μ-X) 2 X 2 } (X = Cl, Br) dimers ( J / k B ≈ 25 and 31 K for 1 and 2 , respectively) or between dimers ( θ ' ≈ 0.30 and 0.47 K for 1 and 2 , respectively) were found at low temperatures. For compounds 3 and 4 , the magnetic susceptibility is well described by the Curie-Weiss law in the temperature range 1.77-300 K with µ eff ≈ 1.72 and 1.70 µ B for 3 and 4 , respectively, and weak antiferromagnetic interactions (θ ≈ -0.4 K for 3 and -0.65 K for 4 ). Complexes 1 - 4 exhibit high catalytic activity in the oxidation of alkanes and alcohols with peroxides. The maximum yield of cyclohexane oxidation products reached 50% (complex 3 ). Based on the data on the study of regio- and bond-selectivity, it was concluded that hydroxyl radicals play a decisive role in the oxidation reaction. The initial products in reactions with alkanes are alkyl hydroperoxides.

A series of heteroleptic square-planar Pt and Pd complexes with bis(diisopropylphenyl) iminoacenaphtene (dpp-Bian) and Cl, 1,3-dithia-2-thione-4,5-dithiolate (dmit), or 1,3-dithia-2-thione-4,5-diselenolate (dsit) ligands have been prepared and characterized by spectroscopic techniques, elemental analysis, X-ray diffraction analysis, and cyclic voltammetry (CV). The intermolecular noncovalent interactions in the crystal structures were assessed by density functional theory (DFT) calculations. The anticancer activity of Pd complexes in breast cancer cell lines was limited by their solubility. Pd(dpp-Bian) complexes with dmit and dsit ligands as well as an uncoordinated dpp-Bian ligand were devoid of cytotoxicity, while the [Pd(dpp-Bian)Cl 2 ] complex was cytotoxic. On the contrary, all Pt(dpp-Bian) complexes demonstrated anticancer activity in a low micromolar concentration range, which was 8-20 times higher than the activity of cisplatin, and up to 2.5-fold selectivity toward cancer cells over healthy fibroblasts. The presence of a redox-active dpp-Bian ligand in Pt and Pd complexes resulted in the induction of reactive oxygen species (ROS) in cancer cells. In addition, these complexes were able to intercalate into DNA, indicating the dual mechanism of action.

Elimination of the chloride ion from the [(PPh 3 )AuCl] complex using silver triflate (AgOTf) in the presence of 2,2'-bipyridine R 2 bpy (the Au : R 2 bpy molar ratio is 2 : 1) in dichloromethane at room temperature leads to dinuclear gold(I) complexes [(PPh 3 Au) 2 (μ-R 2 bpy)](OTf) 2 (R 2 bpy = bpy (1), dbbpy (2), CH 3 Obpy (3), 3-CO 2 CH 3 bpy (4), 4-CO 2 CH 3 bpy (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) Å) 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) Å 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.

A new monoiminoacenaphthenone 3,5-(CF 3 ) 2 C 6 H 3 -mian (complex 2 ) was synthesized and further exploited, along with the already known monoiminoacenaphthenone dpp-mian, to obtain oxidovanadium(IV) complexes [VOCl 2 (dpp-mian)(CH 3 CN)] ( 3 ) and [VOCl(3,5-(CF 3 ) 2 C 6 H 3 -bian)(H 2 O)][VOCl 3 (3,5-(CF 3 ) 2 C 6 H 3 -bian)]·2.85DME ( 4 ) from [VOCl 2 (CH 3 CN) 2 (H 2 O)] ( 1 ) or [VCl 3 (THF) 3 ]. The structure of all compounds was determined using X-ray structural analysis. The vanadium atom in these structures has an octahedral coordination environment. Complex 4 has an unexpected structure. Firstly, it contains 3,5-(CF 3 ) 2 C 6 H 3 -bian instead of 3,5-(CF 3 ) 2 C 6 H 3 -mian. Secondly, it has a binuclear structure, in contrast to 3 , in which two oxovanadium parts are linked to each other through V=O···V interaction. This interaction is non-covalent in origin, according to DFT calculations. In structures 2 and 3 , non-covalent π-π staking interactions between acenaphthene moieties of the neighboring molecules (distances are 3.36-3.40 Å) with an estimated energy of 3 kcal/mol were also found. The redox properties of the obtained compounds were studied using cyclic voltammetry in solution. In all cases, the reduction processes initiated by the redox-active nature of the mian or bian ligand were identified. The paramagnetic nature of complexes 3 and 4 has been proven by EPR spectroscopy. Complexes 3 and 4 exhibited high catalytic activity in the oxidation of alkanes and alcohols with peroxides. The yields of products of cyclohexane oxidation were 43% (complex 3 ) and 27% (complex 4 ). Based on the data regarding the study of regio- and bond-selectivity, it was concluded that hydroxyl radicals play the most crucial role in the reaction. The initial products in the reactions with alkanes are alkyl hydroperoxides, which are easily reduced to their corresponding alcohols by the action of triphenylphosphine (PPh 3 ). According to the DFT calculations, the difference in the catalytic activity of 3 and 4 is most likely associated with a different mechanism for the generation of ● OH radicals. For complex 4 with electron-withdrawing CF 3 substituents at the diimine ligand, an alternative mechanism, different from Fenton's and involving a redox-active ligand, is assumed.

Bi3+ and Pb2+ uptake by a monolacunary Keggin-type [PW11O39]7- anion leads to the formation of [PW11O39Bi]4- and [PW11O39Pb]5- complexes with a stereochemically active lone pair at the incorporated heterometal. The two complexes were isolated as (TBA)4[PW11O39Bi] (1) and (TBA)5[PW11O39Pb] (2) and characterized by 31P and 183W NMR spectroscopy, high-resolution electrospray mass-spectrometry (HR-ESI-MS) and cyclic voltammetry (CV). EXAFS and XANES data confirm the unchanged oxidation state and ψ-square pyramidal geometry of Bi3+ and Pb2+ in 1 and 2. DFT calculations were used in order to (i) confirm the absence of ligands attached to the heterometal sites in both complexes and localize the lone pair, and (ii) assign all signals in the 183W NMR spectra. Complexes 1 and 2 demonstrate photoluminescence (PL). A reversible change in the PL spectra of both complexes in the presence of water vapor has been detected. On the contrary, PL data for sandwich-type ((CH3)4N)4K3[H4(PW11O39)2Bi]·25H2O (3) do not show sensitivity to water vapor.

Reaction of heterometallic cubane-type cluster complexes-[Mo 3 {Pd(dba)}S 4 Cl 3 (dbbpy) 3 ]PF 6 , [Mo 3 {Pd(tu)}S 4 Cl 3 (dbbpy) 3 ]Cl and [Mo 3 {Pd(dba)}S 4 (acac) 3 (py) 3 ]PF 6 , where dba-dibenzylideneacetone, dbbpy-4,4'-di- tert -butyl-2,2'-bipyridine, tu-thiourea, acac-acetylacetonate, py-pyridine, with white phosphorus (P 4 ) in the presence of water leads to the formation of phosphorous acid H 3 PO 3 as the major product. The crucial role of the Pd atom in the cluster core {Mo 3 PdS 4 } has been established in the hydrolytic activation of P 4 molecule. The main intermediate of the process, the cluster complex [Mo 3 {PdP(OH) 3 }S 4 Cl 3 (dbbpy) 3 ] + with coordinated P(OH) 3 molecule and phosphine PH 3 , have been detected by 31 P NMR spectroscopy in the reaction mixture.

Interaction of the tetradentate redox-active 6,6'-[1,2-phenylenebis(azanediyl)]bis(2,4-di-tert-butylphenol) (H 4 L) with TeCl 4 leads to neutral diamagnetic compound TeL (1) in high yield. The molecule of 1 has a nearly planar TeN 2 O 2 fragment, which suggests the formulation of 1 as Te II L 2- , in agreement with the results of DFT calculations and QTAIM and NBO analyses. Reduction of 1 with one equivalent of [CoCp 2 ] leads to quantitative formation of the paramagnetic salt [CoCp 2 ] + [1] .- , which was characterised by single-crystal XRD. The solution EPR spectrum of [CoCp 2 ] + [1] .- at room temperature features a quintet due to splitting on two equivalent 14 N nuclei. Below 150 K it turns into a broad singlet line with two weak satellites due to the splitting on the 125 Te nucleus. Two-component relativistic DFT calculations perfectly reproduce the a( 14 N) HFI constants and A ∥ ( 125 Te) value responsible for the low-temperature satellite splitting. Calculations predict that the additional electron in 1 .- is localised mainly on L, while the spin density is delocalised over the whole molecule with significant localisation on the Te atom (≥30 %). All these data suggest that 1 .- can be regarded as the first example of a structurally characterised monomeric tellurium-nitrogen radical anion., (© 2020 Wiley-VCH GmbH.)

Ovarian cancer is a highly aggressive disease which is treated by surgery and platinum chemotherapy. However, a significant proportion of treated patients develop resistance to platinum treatment resulting in tumor relapse. Acquired platinum resistance has been recently correlated with activation of pro-survival endoplasmic reticulum (ER) stress responses. We hypothesized that Au complexes that induce severe ER stress might counteract pro-survival cellular attempts leading to the ER stress-mediated apoptosis and reduced platinum resistance. In this work, we prepared a series of highly cytotoxic AuI-dialkyldithiocarbamate complexes and investigated their anticancer potential in ovarian cancer cells. Complexes demonstrated surprisingly low stability in chloroform, resulting in the formation of an Au chain polymer, which also displayed excellent cytotoxicity. Lead complex 2 induced oxidative stress and ER stress-mediated p53-independent apoptosis associated with PARP cleavage and cell cycle arrest at G2/M phase. Importantly, 2 caused the surface exposure of calreticulin (CRT), which is the first step in the activation of cellular immunogenic response.

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, WS 2 /MoS 2 , 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 MoS 2 flakes is mixed with a methanolic solution of a cationic W 3 S 4 -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 N 2 leads to the formation of clean WS 2 /MoS 2 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., (© 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.)

A series of novel mono- and binuclear arene-ruthenium(II) complexes [( p -cym)Ru(L)Cl] containing 11 H -indeno[1,2- b ]quinoxalin-11-one derivatives or tryptanthrin-6-oxime were synthesized and characterized by X-ray crystallography, IR, NMR spectroscopy, cyclic voltammetry, and elemental analysis. Theoretical calculations invoking singlet state geometry optimization, solvation effects, and noncovalent interactions were done using density functional theory (DFT). DFT calculations were also applied to evaluate the electronic properties, and time-dependent DFT was applied to clarify experimental UV-vis results. Cytotoxicity for cancerous and noncancerous human cell lines was evaluated with cell viability MTT assay. Complexes demonstrated a moderate cytotoxic effect toward cancerous human cell line PANC-1. The catalytic activity of the complexes was evaluated in transfer hydrogenation of aryl ketones. All complexes exhibited good catalytic activity and functional group tolerance., Competing Interests: The authors declare no competing financial interest., (Copyright © 2020 American Chemical Society.)

Irradiation of the Keggin-type [PW 11 O 39 {Ru(NO)}] 4- ( Ru-NO ) polyoxometalate in CH 3 CN results in rapid NO ligand elimination with the formation of [PW 11 O 39 {Ru III (CH 3 CN)}] 4- ( Ru-CH 3 CN ). This complex offers an easy entry into the Ru-based chemistry of the {PW 11 Ru} complex. Attempts to substitute N 3 - for CH 3 CN in the presence of an NaN 3 excess lead a variety of products: (i) [PW 11 O 39 {Ru III (N 3 )}] 4- ( Ru-N 3 ); (ii) [PW 11 O 39 {Ru III (N 4 HC-CH 3 )}] 4- ( Ru-Tz ) as a click-reaction product; and (iii) [PW 11 O 39 {Ru II (N 2 )}] 5- ( Ru-N 2 ). UV-VIS, CV, and HR-ESI-MS techniques were used for the reaction monitoring and characterization of the products.

The in-gel detection of proteins for various proteomic experiments is commonly done with the fluorescent Ru II tris(bathophenanthroline disulfonate) complex (Ru(BPS) 3 ), which is more cost-effective compared to commercial Ru-based formulations but requires tedious procedures for its preparation and strongly acidic staining conditions. Herein, we report the synthesis and characterization of heteroleptic Ru II complexes Ru(BPS) 2 (BP) and Ru(BPS)(BP) 2 containing bathophenanthroline (BP) and bathophenanthroline disulfonate disodium salt (BPS) in comparison with Ru(BPS) 3 . It was shown by fluorescent and UV-vis measurements that novel Ru II complexes were excitable in both UV and visible light, close to emission bands of classical lasers, which is important for successful in-gel protein detection. Novel fluorescent dyes demonstrated improved protein detection in comparison with commercially available SYPRO Ruby staining solution. In addition, unlike commonly used staining protocols, staining with Ru(BPS)(BP) 2 can be performed at nearly neutral pH, thereby reducing artificial post-translational modifications (PTMs).

Reaction of [SbW 9 O 33 ] 9- with [Pt(H 2 O) 2 (OH) 4 ] results in the first example of the mixed addenda Anderson-Evans type Pt IV {Sb V (OH) 2 }W VI 5 O 22 ] 7- anion, isolated and characterized as K 6 Na 2 [Pt{Sb(OH) 2 }W 5 O 22 ](NO 3 ) 0.1 (OH) 0.9̇ 11H 2 O ( 1 ).

Reactions of [Ru(NO)Cl 5 ] 2- with pseudotrivacant B-α-[XW 9 O 33 ] 9- (X = As III , Sb III ) at 160 °C result in the rearrangement of polyoxometalate backbones into {XM 18 } structures. In the case of arsenic, oxidation of As III to As V takes place with the formation of a mixture of plenary and monosubstituted Dawson [As 2 W 18 O 62 ] 6- and [As 2 W 17 Ru(NO)O 61 ] 7- anions, of which the latter was isolated as Me 2 NH 2 + (DMA-1a and DMA-1b) and Bu 4 N + (Bu 4 N-1) salts and fully characterized. Both α 1 and α 2 isomers of [As 2 W 17 Ru(NO)O 61 ] 7- were present in the reaction mixture; pure [α 2 -As 2 W 17 Ru(NO)O 61 ] 7- was isolated as the Bu 4 N + salt. In the case of antimony, [SbW 9 O 33 ] 9- is converted into a mixture of [SbW 18 O 60 ] 9- and [SbW 17 {Ru(NO)}O 59 ] 10- . The formation of trisubstituted [SbW 15 {Ru(NO)} 3 O 57 ] 12- as a minor byproduct was detected by HPLC-ICP-AES. The monosubstituted [SbW 17 {Ru(NO)}O 59 ] 10- anion was isolated as DMAH + (DMA-2) and mixed inorganic cation (CsKNa-2) salts and characterized by XRD, HPLC-ICP-AES, EA and TGA techniques. X-ray analysis shows the presence of the {Ru(NO)}-group in the 6-membered ("equatorial") belt of the Sb-free hemisphere. The experimental findings were confirmed and interpreted by means of quantum chemical calculations.

Nanoconstructions composed of lipid vesicles and inorganic units (nanoparticles, metal complexes) arouse much interest across materials science and nanotechnology as hybrid materials combining useful functionalities from both parts. Ideally, these units are to be embedded into the bilayer to keep the biophysical performance of lipid vesicles having inorganic moieties screened from the environment. This can be achieved by doping a lipid bilayer with cluster complexes of transition metals. In this work, we report the preparation of nanoparticles from trinuclear W 3 S 4 cluster complexes and egg phosphatidylcholine. A systematic study of their properties was performed by the differential scanning calorimetry, NMR spectroscopy, dynamic light scattering, and transmission electron microscopy. Phospholipids and clusters have been found to spontaneously self-assemble into novel cluster-lipid hybrid materials. The behavior of clusters in the hydrophobic lipid environment is determined by the structure of the ligands and cluster-to-lipid ratio. Intact cluster complexes bearing compact hydrophobic ligands are embedded into the hydrophobic midplane of a lipid bilayer, whereas cluster complexes bearing larger ligands drive the aggregation of lipids and cluster complexes. Considering these differences, it could be possible to obtain different self-assembled associates such as cluster-doped liposomes or lipid-covered crystals. These cluster-lipid hybrids can be a platform for the design of new materials for nanotechnology.

Charge state studies of compounds [Mo 3 S 4 (tu) 8 (H 2 O)]Cl 4 ·4H 2 O (1), [Mo 3 S 4 Cl 3 (dbbpy) 3 ]Cl·5H 2 O (2), [Mo 3 S 4 (CuCl)Cl 3 (dbbpy) 3 ][CuCl 2 ] (3), containing {Mo 3 S 4 } 4+ and {Mo 3 CuS 4 } 5+ cluster cores bearing terminal thiourea (tu) or 4,4'-di-tert-butyl-2,2'-bipyridine (dbbpy) ligands, have been performed by X-ray photoelectron and X-ray emission spectroscopies combined with quantum chemical calculations. The best agreement between theory and experiments has been obtained using the B3LYP method. According to the experimental and calculated data, the Mo atoms are in the oxidation state 4+ for all compounds. The energies and shapes of the Cu2p lines indicate formal oxidation states of Cu as 1+. The coordination of Сu(I) to the cluster {Mo 3 S 4 } in 3 does not lead to significant changes in the charge state of the molybdenum atoms and the {Mo 3 S 4 } unit can be considered as a tridentate metallothia crown ether., (Copyright © 2017 Elsevier B.V. All rights reserved.)

An unprecedented silver-centered P-tetracapped [Ag@Ag 4 (μ 3 -P) 4 ] tetrahedron inscribed within a N 12 icosahedral cage has been discovered in the novel family of luminescent clusters. The latter are easily self-assembled by reacting Ag I salts with tris(2-pyridyl)phosphine (Py 3 P).

Treatment of the triangular [Mo 3 S 4 Cl 3 (dbbpy) 3 ]Cl cluster ([1]Cl) with CuCl produces a novel tetrametallic cuboidal cluster [Mo 3 (CuCl)S 4 Cl 3 (dbbpy) 3 ][CuCl 2 ] ([2][CuCl 2 ]), whose crystal structure was determined by X-ray diffraction (dbbpy = 4,4'-di-tert-butyl-2,2'-bipyridine). This species, which contains two distinct types of Cu(I), is the first example of a diimine-functionalized heterometallic M 3 M'S 4 cluster. Kinetics studies on both the formation of the cubane from the parent trinuclear cluster and its dissociation after treatment with halides, supported by NMR, electrospray ionization mass spectrometry, cyclic voltammetry, and density functional theory calculations, are provided. On the one hand, the results indicate that addition of Cu(I) to [1] + is so fast that its kinetics can be monitored only by cryo-stopped flow at -85 °C. On the other hand, the release of the CuCl unit in [2] + is also a fast process, which is unexpectedly assisted by the CuCl 2 - counteranion in a process triggered by halide (X - ) anions. The whole set of results provide a detailed picture of the assembly-disassembly processes in this kind of cluster. Interconversion between trinuclear M 3 S 4 clusters and their heterometallic M 3 M'S 4 derivatives can be a fast process occurring readily under the conditions employed during reactivity and catalytic studies, so their occurrence is a possibility that must be taken into account in future studies.

Whereas the cluster [Mo3 S4 (acac)3 (py)3 ](+) ([1](+) , acac=acetylacetonate, py=pyridine) reacts with a variety of alkynes, the cluster [W3 S4 (acac)3 (py)3 ](+) ([2](+) ) remains unaffected under the same conditions. The reactions of cluster [1](+) show polyphasic kinetics, and in all cases clusters bearing a bridging dithiolene moiety are formed in the first step through the concerted [3+2] cycloaddition between the C≡C atoms of the alkyne and a Mo(μ-S)2 moiety of the cluster. A computational study has been conducted to analyze the effect of the metal on these concerted [3+2] cycloaddition reactions. The calculations suggest that the reactions of cluster [2](+) with alkynes feature ΔG(≠) values only slightly larger than its molybdenum analogue, however, the differences in the reaction free energies between both metal clusters and the same alkyne reach up to approximately 10 kcal mol(-1) , therefore indicating that the differences in the reactivity are essentially thermodynamic. The activation strain model (ASM) has been used to get more insights into the critical effect of the metal center in these cycloadditions, and the results reveal that the change in reactivity is entirely explained on the basis of the differences in the interaction energies Eint between the cluster and the alkyne. Further decomposition of the Eint values through the localized molecular orbital-energy decomposition analysis (LMO-EDA) indicates that substitution of the Mo atoms in cluster [1](+) by W induces changes in the electronic structure of the cluster that result in weaker intra- and inter-fragment orbital interactions., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Reaction of [Nb6O19](8-) with [Pt(OH)4(H2O)2] upon heating yielded first characterized platinum polyniobates. A dimeric complex [Nb6O19{Pt(OH)2}]2(12-) (1) is produced in a 1 : 1 molar ratio. Increasing the Pt/Nb6 molar ratio to 1 : 2 yields a mixture of 1 and a sandwich-type complex [Pt(Nb6O19)2](12-) (2).

A study, involving kinetic measurements on the stopped-flow and conventional UV/Vis timescales, ESI-MS, NMR spectroscopy and DFT calculations, has been carried out to understand the mechanism of the reaction of [Mo3 S4 (acac)3 (py)3 ][PF6 ] ([1]PF6 ; acac=acetylacetonate, py=pyridine) with two RCCR alkynes (R=CH2 OH (btd), COOH (adc)) in CH3 CN. Both reactions show polyphasic kinetics, but experimental and computational data indicate that alkyne activation occurs in a single kinetic step through a concerted mechanism similar to that of organic [3+2] cycloaddition reactions, in this case through the interaction with one Mo(μ-S)2 moiety of [1](+) . The rate of this step is three orders of magnitude faster for adc than that for btd, and the products initially formed evolve in subsequent steps into compounds that result from substitution of py ligands or from reorganization to give species with different structures. Activation strain analysis of the [3+2] cycloaddition step reveals that the deformation of the two reactants has a small contribution to the difference in the computed activation barriers, which is mainly associated with the change in the extent of their interaction at the transition-state structures. Subsequent frontier molecular orbital analysis shows that the carboxylic acid substituents on adc stabilize its HOMO and LUMO orbitals with respect to those on btd due to better electron-withdrawing properties. As a result, the frontier molecular orbitals of the cluster and alkyne become closer in energy; this allows a stronger interaction., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

Two new hybrid molybdenum(IV) Mo3 S7 cluster complexes derivatized with diimino ligands have been prepared by replacement of the two bromine atoms of [Mo3 S7 Br6 ](2-) by a substituted bipyridine ligand to afford heteroleptic molybdenum(IV) Mo3 S7 Br4 (diimino) complexes. Adsorption of the Mo3 S7 cores from sample solutions on TiO2 was only achieved from the diimino functionalized clusters. The adsorbed Mo3 S7 units were reduced on the TiO2 surface to generate an electrocatalyst that reduces the overpotential for the H2 evolution reaction by approximately 0.3 V (for 1 mA cm(-2) ) with a turnover frequency as high as 1.4 s(-1) . The nature of the actual active molybdenum sulfide species has been investigated by X-ray photoelectron spectroscopy. In agreement with the electrochemical results, the modified TiO2 nanoparticles show a high photocatalytic activity for H2 production in the presence of Na2 S/Na2 SO3 as a sacrificial electron donor system., (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

The first Keggin-type Be-containing heteropolyanion [BeW12O40](6-) (1(6-)) has been obtained by hydrothermal synthesis from sodium tungstate and Be(NO3)2. It was crystallized as (Bu4N)4.8Na1.2[BeW12O40] (1a) and (Me2NH2)6[BeW12O40]·4H2O (1b) salts, which were characterized by (9)Be and (183)W NMR, ESI-MS, CV, and single crystal X-ray diffraction analysis.

Bifunctional dithiolene ligands have been coordinated to the Mo(V)(O)(μ-S2)Mo(V)(O) unit to afford [Mo2O2(μ-S)2(BPyDTS2)2](2-) (1(2-)) (BPyDTS2 (2-bis-(2-pyridyl)methylene-1,3-dithiolene) dianions. Reaction of the 1(2-) molybdenum dimer with pentacarbonylchlorothenium(i) affords a tetrametallic complex of formula [Mo2O2(μ-S)2(BPyDTS2)2{Re(CO)3Cl}2](2-) (2(2-)). The monomeric (CH3)2Sn(BPyDTS2) (3) tin complex has also been prepared for comparative purposes. In the structure of (Et4N)2[1], the two metal atoms are in a square pyramidal coordination environment defined by two bridging sulfur atoms, one terminal oxygen atom and the two sulfur atoms of the bifunctional dithiolene ligand. This arrangement leaves two nitrogen atoms on each side which coordinate to two Re atoms in the 2(2-) tetrametallic complex. Compound 3 has a distorted tetrahedral structure defined by two carbon atoms of the methyl groups and two sulfur atoms of the dithiolene ligand. The luminescence properties of all three complexes in acetonitrile have been investigated. Detailed studies supported on quantum mechanical calculations revealed that complex 1(2-) shows photoluminescence in the 600-800 nm region with a maximum wavelength of 628 nm and an emission quantum yield of 0.092, associated with an intraligand charge transfer (ILCT) transition. Coordination of two Re(CO)3Cl fragments to 1(2-) to afford 2(2-) does not affect the emission spectrum and shape although it decreases the quantum yield, approximately by a factor of 4.6. Compound 3 exhibits a similar emission spectrum to those of the complexes 1(2-) and 2(2-) in good agreement with the ILCT assignment. The quantum yield of 3 lies between that of the 1(2-) and 2(2-) complexes.

New Ru-containing polyoxometalate [PW11O39Ru(II)(NO)](4-) (1(4-)) was obtained in high yield by reaction of [Ru(NO)Cl5](2-) with [PW11O39](7-) and characterized by multinuclear NMR, cyclic voltammetry, IR spectroscopy, and electrospray ionization mass spectrometry (ESI-MS). The intrinsic reactivity of the {RuNO} site in 1(4-) toward various reagents has been studied using a versatile and simple ESI tandem mass spectrometric methodology for identification of the L attached at the Ru site; this approach relies on the preferential liberation of the L ligands attached at the Ru sites upon mass-selecting desired intermediates and subsequent promotion of their fragmentation. Reactions with both hydrazine and hydroxylamine lead to elimination of the nitroso group and quantitative formation of [PW11O39Ru(III)(H2O)](4-) (2(4-)) in aqueous solution. In the reaction with hydroxylamine, an intermediate with coordinated dinitrogen has been detected. An easy access to the NH3-coordinated [PW11O39RuNH3](4-) (3(4-)) complex was achieved upon reduction of 1(4-) with Sn(2+) in water.

The synthesis and characterization of an organometallic trinuclear oxo-bridged niobium cluster complex with perpendicularly coordinated mu(3)-eta(2):eta(2)( perpendicular)-acetonitrile ligand in aqueous solution is reported. Reaction of NbCl(5) in acetonitrile with aluminum under argon followed by reaction with aqueous hydrochloric acid affords, after suitable workup, the isolation of the organometallic [Nb(3)(mu-eta(2):eta(2)-NCCH(3))O(3)(H(2)O)(9)](6+) aqua ion by cation-exchange chromatography. The purple niobium aqua ion in 2 M HCl shows a small peak at 365 nm (epsilon approximately 511 M(-1) cm(-1) per Nb) and a broad peak at 565 nm (epsilon approximately 335 M(-1) cm(-1)) in the UV-visible region. It is electron paramagnetic resonance (EPR)-active (g = 1.98), but no hyperfine interaction with the (93)Nb nuclear spin (I = 9/2) was observed. The cyclic voltammogram of [Nb(3)(mu-eta(2):eta(2)-NCCH(3))O(3)(H(2)O)(9)](6+) in 4 M HCl on edge-plane pyrolytic graphite electrode at 50 mV s(-1) in the potential range -1.2 V to +1.1 V (vs SCE) exhibits three anodic peaks at -0.12, +0.53, and +0.85 V and a large cathodic peak at -0.91 V with a slight shoulder at about -0.8 V. The purple aqua ion reacted with potassium thiocyanate to give the green thiocyanate derivative, which was crystallized as ((CH(3))(3)NH)(3)[Nb(3)(mu-eta(2):eta(2)-NCCH(3))O(3)(NCS)(9)].2.5H(2)O (1) and subjected to X-ray structure analysis. Density-functional theory (DFT) calculations fully supported the structure of the cluster.

In our pursuit of mixed chalcogen-bridged cluster complexes, solids of the compositions Mo(3)SSe(6)Br(4) and W(3)SSe(6)Br(4) were prepared using high-temperature synthesis from the elements. Treatment of Mo(3)SSe(6)Br(4) with Bu(4)NBr in a vibration mill yielded (Bu(4)N)(3){[Mo(3)(mu(3)-S)(mu(2)-Se(2))(3)Br(6)]Br} (I). Its all-selenide analogue (Bu(4)N)(3){[Mo(3)(mu(3)-Se)(mu(2)-Se(2))(3)Br(6)]Br} (II) was prepared from Mo(3)Se(7)Br(4) in a similar way. Both compounds were characterized by IR, Raman, and (77)Se NMR spectroscopy. The structure of II was determined by X-ray single-crystal analysis. Compound I is isostructural with II and contains the new Mo(3)(mu(3)-S)Se(6)(4+) cluster core. By treatment of a 4 M Hpts solution of I with PPh(3) followed by cation-exchange chromatography, the new mixed chalcogenido-molybdenum aqua ion, [Mo(3)(mu(3)-S)(mu(2)-Se)(3)(H(2)O)(9)](4+), was isolated and characterized using UV-vis spectroscopy and, after derivatization into [Mo(3)(mu(3)-S)(mu(2)-Se)(3)(acac)(3)(py)(3)](+), electrospray ionization mass spectrometry. From HCl solutions of the aqua ion, a supramolecular adduct with cucurbit[6]uril (CB[6]), {[Mo(3)(mu(3)-S)(mu(2)-Se)(3)(H(2)O)(6)Cl(3)](2)CB[6]}Cl(2) x 11 H(2)O (III), was isolated and its structure determined using X-ray crystallography. W(3)SSe(6)Br(4) upon reaction with H(3)PO(2) gave a mixture of all of the [W(3)S(x)Se(4-x)(H(2)O)(9)](4+) species. After repeated chromatography, crystals of {[W(3)(mu(3)-S)(mu(2)-Se)(3)(H(2)O)(7)Cl(2)](2)CB[6]}Cl(4) x 12 H(2)O (IV) were crystallized from the fraction rich in [W(3)(mu(3)-S)Se(3)(H(2)O)(9)](4+) and structurally characterized.

New ternary and quaternary molybdenum cluster chalcohalides were obtained by high-temperature reactions between Mo, chalcogens, and halogens in evacuated ampules. The crystal structures of [Mo3Se7(TeBr3)Br2]2[Te2Br10] (1), [Mo3Se7(TeI3)I2]I (2), and [Mo3Te7(TeI3)3]2(I)(TeI3) (3) were determined by single-crystal X-ray diffraction. The structures of 1 and 2 consist of positively charged zigzag chains infinity1 [Mo3Se7(TeX3)X4/2] (X=Br, I), with Te2Br102- and I-, respectively, as counterions. The TeI3- and TeBr3- ions function as bidentate ligands in 1 and 2. In 3, TeI3- is not coordinated to the metal but acts as a counterion to the [Mo3Te7(TeI3)3]+ cluster cation.

The reaction of aqueous [W3S7(C2O4)3](2-) with Ln(3+) and Th(4+) in a 1:1 molar ratio leads to oxalate-bridged heteropolynuclear molecular complexes and coordination polymers. La(3+) and Ce(3+) give a layered structure with big (about 1.8 nm) honeycomb pores which are filled with water molecules and lanthanide ions, in {[Ln(H2O)6]3[W3S7(C2O4)3]4}Br x xH2O (Ia and Ib). The smaller Pr(3+), Nd(3+), Sm(3+), Eu(3+), and Gd(3+) ions give discrete nanomolecules [(W3S7(C2O4)3Ln(H2O)5)2(mu-C2O4)] (with a separation of about 3.2 nm between the most distant parts of the molecule), which are further united into zigzag chains by specific S2...Br- contacts to achieve the overall stoichiometry K[(W3S7(C2O4)3Ln(H2O)5)2(mu-C2O4)]Br.xH2O (IIa-IId). Th(4+) gives K2[(W3S7(C2O4)3)4Th2(OH)2(H2O)10] x 14.33H2O (III) with a nanosized discrete anion (with a separation of about 2.7 nm between the most distant parts of the molecule), in which two thorium atoms are bound via two hydroxide groups into the Th2(OH)2(6+) unit, and each Th is further coordinated by five water molecules and two monodentate [W3S7(C2O4)](2-) cluster ligands. All compounds were characterized by X-ray structure analysis and IR spectroscopy. Magnetic susceptibility measurements in the temperature range of 2-300 K show weak antiferromagnetic interactions between two lanthanides atoms for compounds IIa, IIb, and IId. The thermal decomposition of Ia, Ib, and IIb was studied by thermogravimetry.

Single crystals of Ta4S9Br8 are obtained by heating Ta, S, and Br2 at 400 degrees C in a 4.0:9.0:4.0 molar ratio in a 44% yield. The structure was determined by X-ray analysis and consists of molecular clusters [Ta4(mu4-S)(mu-S2)4Br8]. The tantalum atoms form a square with long Ta...Ta distances (3.30 angstroms), with four S2 ligands bridging the Ta-Ta edges and one capping the square. Each Ta atom has two terminal bromine atoms. The compound is diamagnetic and has only two electrons for metal-metal bonding. IR and Raman spectral studies with the use of 34S allow to identify characteristic vibrations S-S (537 cm(-1)) and Ta4-mu4-S (407 cm(-1)). The compound is soluble in CH3CN, giving a dark-red solution with a characteristic electronic spectrum, which was assigned on the base of DFT calculations. ESI-MS spectra of the solutions show formation of [[Ta4S9Br8]Br]- associates.

Heating WTe(2), Te, and Br(2) at 390 degrees C followed by extraction with KCN gives [W(3)Te(7)(CN)(6)](2-). Crystal structures of double salts Cs(3.5)K{[W(3)Te(7)(CN)(6)]Br}Br(1.5).4.5H(2)O (1), Cs(2)K(4){[W(3)Te(7)(CN)(6)](2)Cl}Cl.5H(2)O (2), and (Ph(4)P)(3){[W(3)Te(7)(CN)(6)]Br}.H(2)O (3) reveal short Te(2)...X (X = Cl, Br) contacts. Reaction of polymeric Mo(3)Se(7)Br(4) with KNCSe melt gives [Mo(3)Se(7)(CN)(6)](2-). Reactions of polymeric Mo(3)S(7)Br(4) and Mo(3)Te(7)I(4) with KNCSe melt (200-220 degrees C) all give as final product [Mo(3)Se(7)(CN)(6)](2)(-) via intermediate formation of [Mo(3)S(4)Se(3)(CN)(6)](2-)/[Mo(3)SSe(6)(CN)(6)](2-) and of [Mo(3)Te(4)Se(3)(CN)(6)](2-), respectively, as was shown by ESI-MS. (NH(4))(1.5)K(3){[Mo(3)Se(7)(CN)(6)]I}I(1.5).4.5H(2)O (4) was isolated and structurally characterized. Reactions of W(3)Q(7)Br(4) (Q = S, Se) with KNCSe lead to [W(3)Q(4)(CN)(9)](5-). Heating W(3)Te(7)Br(4) in KCNSe melt gives a complicated mixture of W(3)Q(7) and W(3)Q(4) derivatives, as was shown by ESI-MS, from which E(3)[W(3)(mu(3)-Te)(mu-TeSe)(3)(CN)(6)]Br.6H(2)O (5) and K(5)[W(3)(mu(3)-Te)(mu-Se)(3)(CN)(9)] (6) were isolated. X-ray analysis of 5 reveals the presence of a new TeSe(2-) ligand. The complexes were characterized by IR, Raman, electronic, and (77)Se and (125)Te NMR spectra and by ESI mass spectrometry.

Mechanochemical reaction of cluster coordination polymers 1infinity[M3Q7Br4] (M = Mo, W; Q = S, Se) with solid K2C2O4 leads to cluster core excision with the formation of anionic complexes [M3Q7(C2O4)3]2-. Extraction of the reaction mixture with water followed by crystallization gives crystalline K2[M3Q7(C2O4)3].0.5KBr.nH2O (M = Mo, Q = S, n = 3 (1); M = Mo, Q = Se, n = 4 (2); M = W, Q = S, n = 5 (3)). Cs2[Mo3S7(C2O4)3].0.5CsCl.3.5H2O (4) and (Et4N)1.5H0.5K{[Mo3S7(C2O4)3]Br}.2H2O (5) were also prepared. Close Q...Br contacts result in the formation of ionic triples {[M3Q7(C2O4)3](2)Br}5- in 1-4 and the 1:1 adduct {[Mo3S7(C2O4)3]Br}3- in 5. Treatment of 1 or 2 with PPh(3) leads to chalcogen abstraction with the formation of [Mo3(mu3-Q)(mu2-Q)3(C2O4)3(H2O)3]2-, isolated as (Ph4P)2[Mo3(mu3-S)(mu2-S)3(C2O4)3(H2O)3].11H2O (6) and (Ph4P2[Mo3(mu3-Se)(mu2-Se)3(C2O4)3(H2O)3].8.5H2O.0.5C2H5OH (7). All compounds were characterized by X-ray structure analysis. IR, Raman, electronic, and 77Se NMR spectra are also reported. Thermal decomposition of 1-3 was studied by thermogravimetry.

Black single crystals of Ta(4)Se(9)I(8) are obtained in a high yield by heating Ta, Se, and I(2) at 300 degrees C in 1:2.2:1.0 molar ratio. In the structure, the tantalum atoms form a square, with four Se(2) ligands bridging the Ta-Ta edges and one capping the square. Each Ta atom has two terminal iodine atoms. The compound is diamagnetic and has only two electrons for metal-metal bonding.