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Reaction of SeO2, tetramethylammonium (TMA) chloride, aqueous HCl and Cl2 yields oxochloroselenate with incorporated Cl2 units, TMA3{[Se2O2Cl7](Cl2)}. The main feature of this compound is the strong (up to 3.5 kcal mol−1, according to DFT calculations) Cl⋅⋅⋅Cl bonding, which is also detected by Raman spectroscopy. [ABSTRACT FROM AUTHOR]

Reactions of inorganic macrocyclic polytungstate cavitands K28Li5H7[P8W48O184]·92H2O or Li17(NH4)21H2[P8W48O184]·85H2O with (NH4)[NbO(C2O4)2(H2O)2]·3H2O (Nb–Ox) in aqueous solution lead to incorporation of up to five {NbO(H2O)}3+ units into the {P8W48} cavity. The most stable species contain four {NbO(H2O)}3+ units. The uptake of {NbO(H2O)}3+ was determined by corroborative methods including single crystal XRD, inductively coupled plasma atomic emission spectroscopy (ICP-AES), 31P and 13C nuclear magnetic resonance (NMR), C–H–N elemental analysis (EA) and thermal gravimetric analysis (TGA). Solution speciation of the Nb-encapsulating macrocycles was studied by HPLC-ICP-AES and small angle X-ray scattering (SAXS). [ABSTRACT FROM AUTHOR]

Oxalate ligands in NbV oxalate complexes are labile, making the latter convenient niobium source for preparation of new mixed W/Nb polyoxometalates under mild conditions. Reactions of [NbO(C2O4)2(H2O)2]– with [α‐B‐XW9O33]9– (X = As, Sb) result in formation of sandwich‐type anions. For X = As, [(α‐B‐AsW9O33)2(NbO)3(H2O)]9– and [(α‐B‐AsW9O33)2(NbO)2(H2O)]12– were the products. In the case of antimony, [(α‐B‐SbW9O33)2{Nb(C2O4)}2]12– anion with two trapped {Nb(C2O4)}3+ fragments was isolated and structurally characterized. Solution behavior of the new heteropolyniobotungstates was studied by combined HPLC‐ICP‐AES technique. [ABSTRACT FROM AUTHOR]

A screening of the reactions between BiI3 and iodide salts of different N-alkylated heterocycles (pyridine, quinoline, isoquinoline) resulted in the preparation and structural characterization of six novel iodobismuthate complexes, including two compounds exhibiting an unprecedented {[Bi3I10]} polymeric moiety. It has been shown that the chemical composition and structure of the iodobismuthates significantly affect their optical and electronic properties. In particular, the narrowest band gaps (Eg) were revealed by {[Bi3I10]} iodobismuthates, while the compounds incorporating {[BiI4]} polymeric frameworks showed 0.2–0.3 eV wider Eg. GIXRD analysis evidenced that all three iodobismuthates investigated in thin films show mainly the horizontal (parallel to the substrate) orientation of the 1D polymeric Bi–I frameworks. Such arrangement blocks the charge transport in vertical direction (orthogonal to the substrate) since the conductive Bi–I chains are separated with insulating bulky organic cations. As a consequence, standard planar junction solar cells based on new iodobismuthates revealed low power conversion efficiencies approaching 0.12% only. However, strong in-plane photoconductivity observed for iodobismuthates enabled the fabrication of efficient planar photodetectors, which paves a way to the practical use of this exotic family of materials. Most importantly, the presented systematic study revealed the most general guidelines for future rational design of perovskite-like materials for emerging generation of environment-friendly perovskite photovoltaics emphasizing the importance of the isotropic charge transport in the films of 3D materials and achieving proper orientation of 1D and 2D frameworks with respect to the charge collecting electrodes in anisotropic low dimensional systems. [ABSTRACT FROM AUTHOR]

The aqueous solution chemistry of niobium is underexplored, and well characterized aqua complexes are scarce. In this contribution, a new niobium aqua complex was obtained by treatment of Zn‐reduced ethanolic solution of NbCl5 with HCl in the presence of a selenide source (ZnSe). This is the first example of selenium containing aqua complex of niobium. The yellow‐green aqua complex was isolated by cation‐exchange chromatography and transformed into corresponding isothiocyanate complex by ligand exchange, which was crystallized as (PyH)4.5[H1.5Nb4SeO5(NCS)10]·0.5H2O. X‐ray structural analysis revealed a metal‐metal bonded tetranuclear {Nb4(μ4‐Se)(μ2‐O)5}4+ core with a capping μ4‐Se ligand. [ABSTRACT FROM AUTHOR]

Ligand-exchange reactions of [Mo3S4(tu)8(H2O)]Cl4·4H2O (tu = thiourea) with (PhCH2CH2)2PCH2CH2SR ligands, where R = Ph (PS1), pentyl (PS2) or Pr (PS3), afford new complexes isolated as [Mo3S4Cl3(PS1)3]PF6 ([1]PF6), [Mo3S4Cl3(PS2)3]PF6 ([2]PF6) and [Mo3S4Cl3(PS3)3]PF6 ([3]PF6) salts in 30–50% yields as the major reaction products. The crystal structures of [1]PF6 and [2]PF6 were determined by X-ray diffraction (XRD) analysis. Each of the three phosphine-thioether ligands is coordinated in a bidentate chelating mode to a different molybdenum atom of the Mo3S4 trinuclear cluster; herein, all the phosphorus atoms of the phosphino-thioether ligand are located trans to the capping sulfur (μ3-S). A second product that forms in the reaction of [Mo3S4(tu)8(H2O)]Cl4·4H2O with PS1 corresponds to the neutral [Mo3S4Cl4(PS1)2(PS1*)] complex. Its XRD analysis reveals both bidentate (PS1) and monodentate (PS1*) coordinating modes of the same ligand. In the latter mode the phosphine-thioether is coordinated to a Mo atom only via the P atom. All compounds were characterized using 1H and 31P{1H} NMR spectroscopy, electrospray-ionization (ESI) mass spectrometry and cyclic voltammetry (CV). Reactions of [1]PF6, [2]PF6 and [3]PF6 with an excess of Bu4NCl in CD2Cl2 were followed by 31P{1H} NMR spectroscopy. The spectra indicate equilibrium between cationic [Mo3S4Cl3(PSn)3]+ and neutral [Mo3S4Cl4(PSn)2(PSn*)] (n = 1, 2) species. The equilibrium constants were determined as 2.5 ± 0.2 × 103 M−1, 43 ± 2 M−1 and 30 ± 2 M−1 (at 25 °C) for [1]PF6, [2]PF6 and [3]PF6, respectively, indicating quantitative differences in the hemilabile behaviors of the phosphino-thioether ligands, depending on the substituent at the sulfur. Clusters [1]PF6, [2]PF6 and [3]PF6 were tested as catalysts in the reduction of nitrobenzene to aniline with Ph2SiH2 under mild conditions. Significant differences in the catalytic activities were observed, which can be attributed to different hemilabile behaviors of the PS1 and PS2/PS3 ligands. [ABSTRACT FROM AUTHOR]

The reaction of H3[PW12O40] with (NH4)[NbO(C2O4)2(H2O)2]·3H2O leads to the straightforward incorporation of Nb into a Keggin anion backbone resulting in [PW11NbO40]4− in nearly quantitative yield. Solution behavior of this monosubstituted anion as a function of pH was studied through 31P NMR and HPLC-ICP-AES techniques (a combination of chromatography and ICP-AES). Increasing of the pH leads to the elimination of Nb from the structure with the formation of mixed Nb/W Lindqvist-type anions and monolacunary [PW11O39]7−. In aged solutions of [PW11NbO40]4− the formation of a mixture of [PNb2W10O39]5− isomers was detected. The HPLC-ICP-AES technique was applied for the study of [BW11O39]9− behavior in aqueous solutions at different pH values and for monitoring the [GeW11O39]4− reaction with the niobium oxalate complex. Despite the presence of the nucleophilic Nb=O group [PW11NbO40]4− does not coordinate Co2+ in DMF or Ni2+ in CH3CN, producing double [Co(DMF)6][PW11NbO40]·2.6DMF (2) and [Ni(CH3CN)5.5(H2O)0.5]2[PW11NbO40]·1.7CH3CN (3) salts instead. [ABSTRACT FROM AUTHOR]

Reaction of Mo(CO)6 with Bu4NI and I2 in diglyme yielded a new butterfly MoIII cluster [Mo4OI12]2-. The structure of tetraphenylphosphonium salt was determined by X-ray single crystal diffraction. Ph4P+ and Bu4N+ salts were further characterized by elemental analy-sis, mass spectrometry, energy-dispersive X-ray (EDX), IR, Raman and UV/Vis spectroscopy and CVA studies. The cluster anion has a butterfly array of molybdenum atoms and can be represented as [Mo4(μ4-O)(μ3-I)2(μ2-4)I6]2-. [ABSTRACT FROM AUTHOR]

Reaction of Mo(CO)6 with Bu4NI and I2 in diglyme yielded a new butterfly MoIII cluster [Mo4OI12]2-. The structure of tetraphenylphosphonium salt was determined by X-ray single crystal diffraction. Ph4P+ and Bu4N+ salts were further characterized by elemental analy-sis, mass spectrometry, energy-dispersive X-ray (EDX), IR, Raman and UV/Vis spectroscopy and CVA studies. The cluster anion has a butterfly array of molybdenum atoms and can be represented as [Mo4(μ4-O)(μ3-I)2(μ2-4)I6]2-. [ABSTRACT FROM AUTHOR]

Slow evaporation of water solution of [{ReS}(HO)] generated in situ from [{ReS}(OH)] in presence of γ-cyclodextrin (CD) leads to crystallization of {[{ReS}(HO)] ⊂ [γ-CD]}(NO)·12HO ( 1·12HO) supramolecular complex, which was characterized by single-crystal X-ray diffraction crystallography, IR-spectroscopy, thermogravimetric and elemental analyses. X-ray analysis confirms the formation of 1:1 {[{ReS}(HO)] ⊂ [γ-CD]} inclusion compound in the solid state. However, no adduct formation was detected between [{ReS}(HO)] and γ-cyclodextrin in solution, according to H NMR spectroscopy. In the case of in situ generated [{ReSe}(HO)] the reaction solution with γ-cyclodextrin is unstable and during the crystallization only amorphous precipitate has been obtained. [ABSTRACT FROM AUTHOR]

Reactions of new heterocyclic ligands 2-(pyridin-2-yl)-[1,2,4]triazolo[1,5- a ]quinolin-9-ol ( L-OH ), 2-(pyridin-2-yl)-[1,2,4]triazolo[1,5- a ][1,10]phenanthroline ( L-Py ) and 2-methyl-[1,2,4]triazolo[1,5- a ][1,10]phenanthroline ( L-Me ) with [Re(CO) 5 Br] in toluene afforded the complexes of the general formula [(L)Re(CO) 3 Br]. Substitution of the Br − ligand in [(L)Re(CO) 3 Br] by C 3 F 7 COO − leads to [(L)Re(CO) 3 (OOCC 3 F 7 )] and results in increased emission lifetime. [ABSTRACT FROM AUTHOR]

Reactions between BiCl3, Br2, and chlorides of pyridinium ( 1), 4,4′-propylenedipyridinium ( 2), or trimethylphenylammonium ( 3) in aqueous HCl lead to the formation of chlorobismuthate complexes trapping {Br2} in the solid state into two-dimensional polyhalide supramolecular networks. The nature of non-covalent Br ···Cl interactions was studied by theoretical methods; estimated energies of these interactions are 1.9-6.0 kcal/mol. [ABSTRACT FROM AUTHOR]

A yellow bromobismuthate {(2-BrPy)2H}[BiBr4] ( 1, 2-BrPy=2-bromopyridinium) transforms into the unusually deeply colored cherry-red (2-BrPyH)2[BiBr5] ( 2). A combination of structural studies and theoretical calculations confirms that the appearance of short non-covalent Br⋅⋅⋅Br interactions (≈3.3 Å) in 2 is responsible for the anion-to-cation charge transfer (LP(Brligand)→σ*(Br-C)), yielding dramatic changes in optical behavior. This effect opens the way towards novel halogen bonding-templated halometalate-based hybrid materials with enhanced optical properties. [ABSTRACT FROM AUTHOR]

The reactions between (Bu4N)2[{W6I8}I6] (1) and silver carboxylates RCOOAg in CH2Cl2 afforded new luminescent carboxylate complexes (Bu4N)2[{W6I8}(RCOO)6] [R = CH3 (2), C6H5 (3), C2F5 (4), C3F7 (5), C6F5 (6)]. The complexes were characterized by single-crystal X-ray diffraction, elemental analysis, cyclic vol-tammetry, and IR and NMR spectroscopy. Complexes 1-6 all exhibit intense and long-lived photoluminescence. The carboxylate complexes undergo reversible electrochemical oxidation in two consecutive one-electron steps. [ABSTRACT FROM AUTHOR]

Reaction of Cs[NbO]·14HO with [(CH)RuCl] leads to the formation of trans-[{(CH)Ru}NbO] ( 1). Evaporation of the reaction solution and extraction into methanol (MeOH) yielded Cs[{(CH)Ru}NbO]·8MeOH·2HO ( 1a) as main product together with a small amount of Cs[{(CH)Ru}NbO]·4MeOH·6HO ( 1b), both characterized by X-ray analysis. These structures complete a set of known organometallic polyoxoniobate or polyoxotantalate complexes [{Cp*M′}MO] and [{(CH)Ru}MO] (M = Nb, Ta; M′ = Rh, Ir; x = 1, 2; n = 6, 4; Cp* = η-C(CH)) and give additional information about the importance of cation-anion interactions in the crystal structures of such complexes. [ABSTRACT FROM AUTHOR]

Isolation and structural characterization of three hydrates of a unique series of cluster hydrates [Mo 6 I 8 (OH) 4 (H 2 O) 2 ]· n H 2 O ( n = 14 (h 14 ), 12 (h 12 ), 2 (h 2 )) by controlled hydrolysis of [K(diglyme)(CH 3 CN)] 2 [Mo 6 I 14 ] in borate buffer solutions is reported. The structures of h 14 and h 12 feature three-dimensional hydrogen bond-based frameworks. In particular, the framework in h 12 is close to the frameworks observed in classical clathrate hydrates. In the structure of h 2 the water of crystallization forms discrete (H 2 O) 2 dimers. [ABSTRACT FROM AUTHOR]

This paper summarizes preparations of mixed phosphoniobotungstates [PNbxW12−xO40](3+x)− (x = 1–3) in two different ways: (i) incorporation of Nb into pre-existing lacunary phosphotungstates and (ii) self-assembly reactions. A niobium oxalate complex as the source of niobium is used. The reaction products were monitored by 31P and 183W NMR in solution as well as by 31P MAS NMR techniques for precipitated samples. Single-substituted species [PNbW11O40]4− forms rapidly and selectively from lacunary [PW11O39]7− with one equivalent of [NbO(C2O4)2(H2O)2]−. With the increasing amount of the niobium oxalate the highest number of Nb atoms was found to be three per Keggin anion, but the disubstituted [PNb2W10O40]5− was always the preferable product whatever the tungsten reagent was. The reaction products with x = 2 and 3 are present as mixtures of all possible isomers, but the ratio between the individual isomers depends on the synthetic pathway. [ABSTRACT FROM AUTHOR]