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Shmelev, M. A., T. D. Shatrov, O. V. Zvereva, A. A. Levina, Yu K. Voronina, A. A. Sidorov i I. L. Eremenko. "Mixed-Carboxylate Cadmium–Europium Compounds with Monocarboxylic Acid Anions". Russian Journal of Coordination Chemistry 50, nr 8 (sierpień 2024): 557–66. http://dx.doi.org/10.1134/s1070328424600554.
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Koksharova, T. V., A. Yu Kovalyov, T. V. Mandzii i Ye M. Fadieiev. "COORDINATION COMPOUNDS OF 3d-METALS 5-SULFOSALICYLATES". Odesa National University Herald. Chemistry 29, nr 1(87) (28.06.2024): 5–20. http://dx.doi.org/10.18524/2304-0947.2024.1(87).307855.
Pełny tekst źródłaStreszczenie:
The review is devoted to the characteristic of 3d-metal coordination compounds with 5-sulfosalicylate anions and their mixed- ligand complexes. Their preparation, structure, properties and applications are considered.
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Sánchez-Lara, Eduardo, Amalia García-García, Enrique González-Vergara, Javier Cepeda i Antonio Rodríguez-Diéguez. "Magneto-structural correlations of cyclo-tetravanadates functionalized with mixed-ligand copper(ii) complexes". New Journal of Chemistry 45, nr 11 (2021): 5081–92. http://dx.doi.org/10.1039/d0nj06004f.
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Bimetallic materials based on tetravanadate anions and mixed ligand copper(ii) complexes were readily synthesized under non-hydrothermal conditions. The compounds show interesting structural and magnetic diversity mediated by copper symmetry.
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Mazhenov, N. A., i Z. R. Syzdykova. "The formation of the mixed anions PAsO7 in solid solutions Mg2P2O7 — Mg2As2O7". Bulletin of the Karaganda University. "Physics" Series 105, nr 1 (30.03.2022): 117–22. http://dx.doi.org/10.31489/2022ph1/117-122.
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The article presents structural features at formation of solid solutions of the isostructural Mg2P2O7 and Mg2As2O7 connections. In these compounds, complex Р2О7 4- anions, As2O2 4- , as well as the formation of complex PAsO7 4 anions, is not natural. The formation of solid solutions is confirmed by the linear dependence of x-ray debaegram and optical refractive indices, depending on the concentration of P/As. In the article, phosphates are involved in energy processes in cells. For the first time, the formation of mixed anions in polyphosphates has been proven. The oscillatory spectra of pyro anions have intervals of localization of terminal and bridging groups of atoms that have no intersection regions. Strip at 662–670 cm-1 (between structures from P: As=0.8:0.2 to 0.1–0.9), located between vsPOP frequency in ᵦ — Mg2P2O7 at 737 cm-1 and the frequencies about 550 cm-1 characteristic of fluctuations of vsAsOAs in alkaline pyroarsenates, is interpreted as a strip of fluctuations of vsPOAs of the mixed PAsO7 ions. In the area, the strip at 925–902 cm-1 is located between frequencies of fluctuations of vasPOP and vasAsOAs. The fluctuations of mastic group P-O found in ranges of infrared absorption allow establishing knowledge of the adjacent anions (PAsO7 ) 4- that it is possible to confirm with quantum-chemical calculations in the subsequent.
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Ehlich, Hendrik, Annette Schier i Hubert Schmidbaur. "Preparation and Crystal Structure of Bis(isocyanide)gold(I) Bis(phenylene-1,2-dithiolato)aurates(III)". Zeitschrift für Naturforschung B 57, nr 8 (1.08.2002): 890–94. http://dx.doi.org/10.1515/znb-2002-0808.
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The reaction of (isocyanide)gold(I) chlorides [(RNC)AuCl, R = tBu, cHex] with phenylene- 1,2-dithiol and sodium methoxide (molar ratio 2:1:2) in methanol / dichloromethane leads to the formation of deep green mixed-valent salts [(RNC)2Au]+[Au(S2C6H4)2]- in ca. 35% yield. As determined by single crystal X-ray diffraction methods, the two compounds have entirely different supramolecular structures. For R = tBu stacked planar anions and rod-like cations form alternating layers, while for R = cHex alternating cations and anions are arranged in chains with long S- -Au contacts [3.422 Å].
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Fábry, Jan, Michaela Fridrichová, Michal Dušek, Karla Fejfarová i Radmila Krupková. "Mixed crystals of 2-carbamoylguanidinium with hydrogen fluorophosphonate and hydrogen phosphite in the ratios 1:0, 0.76 (2):0.24 (2) and 0.115 (7):0.885 (7)". Acta Crystallographica Section C Crystal Structure Communications 68, nr 2 (6.01.2012): o76—o83. http://dx.doi.org/10.1107/s0108270111054114.
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The title compounds, 2-carbamoylguanidinium hydrogen fluorophosphonate, C2H7N4O+·HFO3P−, (I), 2-carbamoylguanidinium–hydrogen fluorophosphonate–hydrogen phosphite (1/0.76/0.24), C2H7N4O+·0.76HFO3P−·0.24H2O3P−, (II), and 2-carbamoylguanidinium–hydrogen fluorophosphonate–hydrogen phosphite (1/0.115/0.885), C2H7N4O+·0.115HFO3P−·0.885H2O3P−, (III), are isostructural with guanylurea hydrogen phosphite, C2H7N4O+·H2O3P−[Fridrichová, Němec, Císařová & Němec (2010).CrystEngComm,12, 2054–2056]. They constitute structures where the hydrogen phosphite anion has been fully or partially replaced by hydrogen fluorophosphonate. The title structures are the fourth example of isostructural compounds which differ by the presence of hydrogen fluorophosphonate and hydrogen phosphite or fluorophosphonate and phosphite anions. Moreover, the present study reports structures with these mixed anions for the first time. In the reported mixed salts, the P and O atoms of either anion overlap almost exactly, as can be judged by comparison of their equivalent isotropic displacement parameters, while the P—F and P—H directions are almost parallel. There are strong O—H...O hydrogen bonds between the anions, as well as strong N—H...O hydrogen bonds between the 2-carbamoylguanidinium cations in the title structures. Altogether they form a three-dimensional hydrogen-bond pattern. Interestingly, rare N—H...F interactions are also present in the title structures. Another exceptional feature concerns the P—O(H) distances, which are about as long as the P—F distance. The dependence of P—F distances on the longest P—O distances in FO3P2−or HFO3P−is presented. The greater content of hydrogen phosphite in the mixed crystals causes a larger deformation of the cations from planarity.
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Herberhold, Max, Guo-Xin Jin, Achim Müller i Michael Penk. "The Reactions of Dioxobis(acetylacetonato)moIybdenum, MoO2(acac)2, with Tetrathiomolybdate and Tetrathiotungstate. High Formation Tendency of the {Mvi(μ-S)2Miv} (μ-S )2MVI} Group and the [MVI,S3(S2)]2- Type Ligand (M = Mo, W)". Zeitschrift für Naturforschung B 46, nr 1 (1.01.1991): 25–34. http://dx.doi.org/10.1515/znb-1991-0107.
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1Tetraphenylphosphonium tetrathiometalates, (PPh4)2MS4 (M = Mo, W), react with MoO2 (acac)2 (2:1) in boiling acetonitrile in redox processes to give mixed-crystal compounds (as expected) of the approximate composition (PPh4)2[Mo3O1.9S8.1] (1) and (PPh4)2[Mo1.4W1.6O1.3S8.3] (2), respectively. and 2 were characterized by single crystal X-ray structure analyses. The various anions o f 1 and 2 contain {MVI(μ-S)2MoIVO (μ-S )2MVI} cores (M = Mo (1); Mo, W (2); bond angle M ··· Mo ··· M = 151.3° (1) 152.2 - 154.3° (2)), which have high formation tendencies. The terminal positions are occupied by S and O atoms. The trinuclear anions of 1 correspond to the type [XYMo(μ-S)2MoO(μ-S)2MoSX ]2- (X = O, S; Y = S, S2). In 2 there are two sets of anions of the type [XYM(μ-S)2MoO(μ-S)2WS2]2- and [ZSM (μ-S)2MoO(μ-S)2MZS]2- (Z = Sn/Om) in the ratio o f 2:1, occupying two symmetry-independent sites in the unit cell. Complex 2 is the first structurally characterized mixed-metal Mo - W thiometalate.
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Černý, Radovan, Matteo Brighi i Fabrizio Murgia. "The Crystal Chemistry of Inorganic Hydroborates". Chemistry 2, nr 4 (29.09.2020): 805–26. http://dx.doi.org/10.3390/chemistry2040053.
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The crystal structures of inorganic hydroborates (salts and coordination compounds with anions containing hydrogen bonded to boron) except for the simplest anion, borohydride BH4−, are analyzed regarding their structural prototypes found in the inorganic databases such as Pearson’s Crystal Data [Villars and Cenzual (2015), Pearson’s Crystal Data. Crystal Structure Database for Inorganic Compounds, Release 2019/2020, ASM International, Materials Park, Ohio, USA]. Only the compounds with hydroborate as the only type of anion are reviewed, although including compounds gathering more than one different hydroborate (mixed anion). Carbaborane anions and partly halogenated hydroborates are included. Hydroborates containing anions other than hydroborate or neutral molecules such as NH3 are not discussed. The coordination polyhedra around the cations, including complex cations, and the hydroborate anions are determined and constitute the basis of the structural systematics underlying hydroborates chemistry in various variants of anionic packing. The latter is determined from anion–anion coordination with the help of topology analysis using the program TOPOS [Blatov (2006), IUCr CompComm. Newsl. 7, 4–38]. The Pauling rules for ionic crystals apply only to smaller cations with the observed coordination number within 2–4. For bigger cations, the predictive power of the first Pauling rule is very poor. All non-molecular hydroborate crystal structures can be derived by simple deformation of the close-packed anionic lattices, i.e., cubic close packing (ccp) and hexagonal close packing (hcp), or body-centered cubic (bcc), by filling tetrahedral or octahedral sites. This review on the crystal chemistry of hydroborates is a contribution that should serve as a roadmap for materials engineers to design new materials, synthetic chemists in their search for promising compounds to be prepared, and materials scientists in understanding the properties of novel materials.
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Schneider, Daniel, i Annette Schier. "Random Interstitial Halide Accommodation in an α,ω-Alkylidene-diammonium Template". Zeitschrift für Naturforschung B 59, nr 11-12 (1.12.2004): 1395–99. http://dx.doi.org/10.1515/znb-2004-11-1205.
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N,N,N′,N′-Tetramethylethylenediammonium diiodide [Me2HNCH2]2I2 (1) as well as a set of I/Br- (2) and Br/Cl-mixed-halide salts (4 and 5) have been prepared, and their structures determined by single crystal X-ray diffraction. The results show the [Me2HNCH2]2 2+ dication to be a highly flexible template for halide inclusion, thereby tolerating the assembly of anions of different size, with phase widths of 0 ≤ x ≤ 2 for a monoclinic form with [Me2HNCH2]2I2−xBrx and 0 ≤ x ≤ 1 for a triclinic form with [Me2HNCH2]2Br2−xClx. The isotypic mixed halide compounds [Me2HNCH2]2IBr (2) and [Me2HNCH2]2BrCl (4) exhibit a statistical distribution of the anions in a structure of space group P21/c which is also found for the pure diiodide [Me2HNCH2]2I2 (1). With an excess of chloride (x>1 for Br2−xClx) this structure is converted into that of the pure dichloride, [Me2HNCH2]2Cl2 (6), with space group P1̅. In all cases the halide anions are trapped in voids between the dications and fixed to the ammonium centers by strong N-H· · ·X and weak C-H· · ·X hydrogen bonding.
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Zelikman, V. M., K. I. Maslakov, I. A. Ivanin i I. G. Tarkhanova. "Using Immobilized Hybrid Composites Based on Mixed Polyoxometalates As Catalysts for the Oxidation of Heteroatomic Compounds". Журнал физической химии 97, nr 9 (1.09.2023): 1239–47. http://dx.doi.org/10.31857/s0044453723090273.
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A set of silica gel-immobilized compounds is synthesized that consists of ethylimidazole cations and anions of phosphotungstic acid (lacunar (PW11) or mixed (PW11M), where M = Zn, Ni, Cu, Co, Mn). The composition and textural characteristics of the compounds are determined by physicochemical means (IR spectroscopy, XPS, SEM/EDX, adsorption). The synthesized heterogeneous composites are active in the oxidation of sulfur- and nitrogen-containing components of petroleum feedstocks with hydrogen peroxide. A comparative analysis is performed of the samples’ catalytic properties in the oxidation of both individual substrates (thiophene, dibenzothiophene, methyl phenyl sulfide, pyridine) and their mixtures.
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Matveev, Evgenii Yu, Varvara V. Avdeeva, Konstantin Yu Zhizhin, Elena A. Malinina i Nikolay T. Kuznetsov. "Effect of Nature of Substituents on Coordination Properties of Mono- and Disubstituted Derivatives of Boron Cluster Anions [BnHn]2– (n = 10, 12) and Carboranes with exo-Polyhedral B–X Bonds (X = N, O, S, Hal)". Inorganics 10, nr 12 (2.12.2022): 238. http://dx.doi.org/10.3390/inorganics10120238.
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This review systematizes data on the coordination ability of mono- and disubstituted derivatives of boron cluster anions and carboranes in complexation with transition metals. Boron clusters anions [BnHn]2–, monocarborane anions [CBnHn–1]–, and dicarboranes [C2BnHn–2] (with non-functionalized carbon atoms) (n = 10, 12) containing the B–X exo-polyhedral bonds (X = N, O, S, Hal) are discussed. Synthesis and structural features of complexes known to date are described. The effect of complexing metal and substituent attached to the boron cage on the composition and structures of the final complexes is analyzed. It has been established that substituted derivatives of boron cluster anions and carboranes can act as both ligands and counterions. A complexing agent can coordinate substituted derivatives of the boron cluster anions due to three-center two-electron 3c2e MHB bonds, by the substituent functional groups, or a mixed type of coordination can be realized, through the BH groups of the boron cage and the substituent. As for B-substituted carboranes, complexes with coordinated substituents or salts with non-coordinated carborane derivatives have been isolated; compounds with MHB bonding are not characteristic of carboranes.
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Tukumova, Natalia V., Tatiana R. Usacheva, Tran Thi Dieu Thuan, Valentin A. Sharnin i Concetta Giancola. "STABILITY OF COORDINATION COMPOUNDS OF SOME d-METAL IONS WITH SUCCINIC ACID ANION IN AQUEOUS-ETHANOL SOLVENTS". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 61, nr 9-10 (22.10.2018): 15–22. http://dx.doi.org/10.6060/ivkkt20186109-10.5778.
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The paper provides an overview of own data on complexation of nickel (II), cobalt (II) and cooper (II) ions with succinic acid anion in water-organic mixed solvents. Proper data are compared with data reported in literature for d-metal complexes with anions of maleic and succinic acids. The effect of aqueous ethanol solvent compositions on the stability of coordination compounds of M2+ with succinic acid anion as well as on рК values of stepwise succinic acid dissociation was carried out by a potentiometric titration at ionic strength of 0.1 maintained with sodium perchlorate at 298.15 ± 0.10 K. Mono ligand complexes of Ni2+, Co2+ and Cu2+ ions with succinic acid anion become stronger when ethanol content rises. In aqueous solutions Cu2+ ion forms stronger complexes with succinic and maleic acid anions than Ni2+ and Co2+ ions. In the studied water - ethanol solution this ratio is maintained for complexes with succinic acid anion, but a water-isopropanol solvent exerts leveling effect on the stability of complexes of nickel (II) and cobalt (II). An increase in the stability of complexes of d-metal with anions of maleic and succinic acids is due to the destabilization of the ligand with increasing ethanol concentration. The principal contribution of the changes in the solvation state of ligand is a typical for the stability changes of d-metal complexes with amine, glycinate, and acetate type ligands in water-organic mixed solvents.
For citation:
Tukumova N.V., Usacheva T.R., Thuan Tran Thi Dieu, Sharnin V.A., Giancola C. Stability of coordination compounds of some d-metal ions with succinic acid anion in aqueous-ethanol solvents. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2018. V. 61. N 9-10. P. 15-22
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Chondroudis, Konstantinos, i Mercouri G. Kanatzidis. "K4In2(PSe5)2(P2Se6) and Rb3Sn(PSe5)(P2Se6): One-Dimensional Compounds with Mixed Selenophosphate Anions". Journal of Solid State Chemistry 136, nr 1 (luty 1998): 79–86. http://dx.doi.org/10.1006/jssc.1997.7659.
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Stüble, Pirmin, Angela Berroth i Caroline Röhr. "Synthesis and crystal structure of new K and Rb selenido/tellurido ferrate cluster compounds". Zeitschrift für Naturforschung B 71, nr 5 (1.05.2016): 485–501. http://dx.doi.org/10.1515/znb-2015-0223.
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AbstractIn the course of a systematic study of alkali iron chalcogenido salts containing clusters [Fe4Q8] a series of new mixed-valent potassium and rubidium selenido and tellurido ferrates(II/III) was synthesized by carefully heating the pure elements enclosed in sample tubes under an argon atmosphere up to maximum temperatures of 800–900 °C. Their crystal structures have been determined by means of single crystal X-ray diffraction. The mixed-valent FeII/III tellurido ferrates A7[Fe4Te8] form three different structure types. All structures contain tetramers of four edge sharing [FeTe4] tetrahedra, which are connected by common edges to form only slightly distorted tetrahedral [Fe4Te8]7− anions (‘stella quadrangula’) with a [Fe4Te4] cubane core. In all cases, these anions are surrounded by 26 alkali cations, which are located at the eight corners and the midpoints of the six faces and 12 edges of a cube. The three crystal structures can thus be described by three different packings of cuboid moieties: The monoclinic rubidium compound Rb7[Fe4Te8] (space group C2/c, a = 2000.16(7), b = 897.79(3), c = 1768.12(6) pm, β = 117.4995(10)°, Z = 4, R1 = 0.0296) is isotypic to the known cesium tellurido and sulfido ferrates Cs7[Fe4(S/Te)8]. Depending on the temperature, K7[Fe4Te8] forms two different but closely related new structure types: The tetragonal r.t. modification (space group P42/nmc, a = 1222.25(14), c = 872.1(2) pm, Z = 2, R1 = 0.0583) crystallizes in a supergroup of the orthorhombic l.t. (100 K) form (space group Pbcn, a = 1715.5, b = 866.76(3), c = 1715.50(7) pm, Z = 4, R1 = 0.0160). In all structures, the cluster centered cubes are stacked to form columns along the short (≈870 pm) axis. These columns are themselves densely packed with 4 (both K compounds) and 6 (A = Rb) adjacent face-sharing columns. According to these arrangements of cluster-centered cubes, a relation of the packing of K/Rb cations and cluster anions with the simple cubic packing can be established applying the crystallographic group-subgroup formalism. Attempts to synthesize the corresponding selenium compound K7[Fe4Se8] resulted in the formation of the likewise mixed-valent compound K6[Fe4Se8]. Despite the modified composition, the new orthorhombic structure (space group Pbcn, a = 1632.62(6), b = 821.10(3), c = 1592.75(6) pm, Z = 4, R1 = 0.0540) is almost isotypic to the l.t. form of K7[Fe4Te8], the only difference being a missing K site. K5Fe2Te5 crystallizes in a new structure type (cubic, space group Pa3̅, a = 1709.02(5) pm, Z = 4, R1 = 0.0594). According to K5Fe2Te5=K15[Fe3Te7]2(Te), its structure contains mixed-valent cuboidal trimers [Fe3Te7](6/7)− and isolated telluride ions, which are coordinated by cubes of K+ cations.
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Mehrotra, Raj Narain. "Review on the Chemistry of [M(NH3)n](XO4)m (M = Transition Metal, X = Mn, Tc or Re, n = 1–6, m = 1–3) Ammine Complexes". Inorganics 11, nr 7 (20.07.2023): 308. http://dx.doi.org/10.3390/inorganics11070308.
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The preparation of ammine complexes of transition metals having oxidizing anions such as permanganate and perrhenate ions is a great challenge due to possible reactions between ammonia and oxidizing anions during the synthesis of these materials. However, it has an important role in both the development of new oxidants in organic chemistry and especially in the preparation of mixed-metal oxide catalyst precursors and metal alloys for their controlled temperature decomposition reactions. Therefore, in this paper, synthetic procedures to prepare ammonia complexes of transition metal permanganate, pertechnetate, and perrhenate (the VIIB group tetraoxometallates) salts have been comprehensively reviewed. The available data about these compounds’ structures and spectroscopic properties, including the presence of hydrogen bonds that act as redox reaction centers during thermal decomposition, are given and evaluated in detail. The nature of the thermal decomposition products has also been summarized. The available information about the role of the ammine complexes of transition metal permanganate salts in organic oxidation reactions, such as the oxidation of benzyl alcohols and regeneration of oxo-compounds from oximes and phenylhydrazones, including the kinetics of these processes, has also been collected. Their physical and chemical properties, including the thermal decomposition characteristics of known diammine (Ag(I), Cd, Zn, Cu(II), Ni(II)), triammine (Ag(I)), and simple or mixed ligand tetraammine (Cu(II), Zn, Cd, Ni(II), Co(II), Pt(II), Pd(II), Co(III)), Ru(III), pentaammine (Co(III), Cr(III), Rh(III) and Ir(III)), and hexaammine (Ni(II), Co(III), Cr(III)) complexes of transition metals with tetraoxometallate(VII) anions (M = Mn, Tc and Re), have been summarized. The preparation and properties of some special mixed ligand/anion/cation-containing complexes, such as [Ru(NH3)4(NO)(H2O)](ReO4)2, [Co(NH3)5(H2O)](ReO4)2, [Co(NH3)5X](MnO4)2 (X = Cl, Br), [Co(NH3)6]Cl2(MnO4), [Co(NH3)5ReO4]X2 (X = Cl, NO3, ClO4, ReO4), and K[Co(NH3)6]Cl2(MnO4)2, are also included.
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Grossholz, Hagen, Dirk D. Zimmermann, Oliver Janka i Thomas Schleid. "Oxidfluoridsulfide der Lanthanoide vom Formeltyp M6O2F8S3 (M=La–Nd, Sm, Gd) / Oxide Fluoride Sulfides of the Lanthanoids with the Formula M6O2F8S3 (M = La–Nd, Sm, Gd)". Zeitschrift für Naturforschung B 68, nr 7 (1.07.2013): 751–60. http://dx.doi.org/10.5560/znb.2013-3110.
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The lanthanoid(III) oxide fluoride sulfides M6O2F8S3 (M = La-Nd, Sm, Gd) can be obtained by reacting the rare-earth metals, their trifluorides and sesquioxides with elemental sulfur in appropriate molar ratios at 850 °C flux-assisted by NaCl in gas-tightly sealed niobium or tantalum ampoules. All compounds are colorless, except for those containing M = Pr with green, M = Nd with lilac and M = Sm with yellow color. They form transparent single crystals as needles or rods. The M6O2F8S3 representatives crystallize in a hexagonal structure (space group: P63/m; a≈1382 - 1326, c≈398 - 376 pm, c/a≈0:288 - 0.284; Z =2) with two different crystallographic M3+ positions. The (M2)3+ cations reside in ninefold coordination of anions arranged as tricapped trigonal prisms formed by three F-, four mixed-occupied O2-/F- and two S2- anions, resembling the unique M3+ coordination sphere of the M3OF5S-type oxide fluoride sulfides. The (M1)3+ cations are surrounded by square antiprisms built of four O2-/F- and S2- anions each, which are capped by one F- anion each, again resulting in a ninefold coordination similar to that of the A-MFS-type fluoride sulfides. While the crystallographically unique S2- anions have six cationic neighbors arranged in trigonal prisms, there are four different light-anion positions. Two of them, representing only fluoride anions, are situated in a triangular environment of cations ((F1)-: planar, (F2)-: non-planar). The mixed-occupied light-anion positions (F3)-=(O3)2- and (F4)-=(O4)2- exhibit tetrahedral coordination spheres with a ratio F- :O2- =2 : 1. The M6O2F8S3 arrangement is characterized by an empty hexagonal channel structure created by (F1)- anions with a potential of accommodating alkali-metal cations like Na+. All single-crystal X-ray structure investigations did not indicate any ordering of the O2- and F- anions, but MAPLE calculations revealed a slightly favored oxygen occupation for the (F4)-=(O4)2- rather than for the (F3)-=(O3)2- position. Electron-beam microanalyses gave no evidence for the incorporation of either Na+ or Cl- ions stemming from NaCl used as the flux.
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Luo, Zhong-Zhen, Chen-Sheng Lin, Wen-Dan Cheng, Yi Yang, Yuan-Bing Li, Hao Zhang, Wei-Long Zhang i Zhang-Zhen He. "Syntheses, crystal and electronic structures, and characterizations of the mixed anions compounds Ba4In2Te2Q5 (Q = S, Se)". CrystEngComm 15, nr 23 (2013): 4773. http://dx.doi.org/10.1039/c3ce40487k.
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Matveev, Evgenii Yu, Varvara V. Avdeeva, Alexey S. Kubasov, Konstantin Yu Zhizhin, Elena A. Malinina i Nikolay T. Kuznetsov. "Synthesis and Structures of Lead(II) Complexes with Hydroxy-Substituted Closo-Decaborate Anions". Inorganics 11, nr 4 (28.03.2023): 144. http://dx.doi.org/10.3390/inorganics11040144.
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Mixed-ligand lead(II) complexes with 2,2′-bipyridyl and [B10H9OH]2− or monosubstituted hydroxy-substituted closo-decaborate anions with a pendant hydroxy group, separated from the boron cage by an alkoxylic spacer of different lengths [B10H9O(CH2)xO(CH2)2OH]]2− (x = 2 or 5) have been synthesized. Compounds have been characterized by IR and multinuclear NMR spectroscopies. The structures of binuclear complex [Pb(bipy)2[B10H9OH]]2·CH3CN (1·CH3CN), mononuclear complex [Pb(bipy)2[B10H9O(CH2)2O(CH2)2OH]]·0.5bipy·CH3CN (2·0.5bipy·CH3CN), and polymeric complex [Pb(bipy)[B10H9O(CH2)5O(CH2)2OH]]n (3) have been determined by single-crystal X-ray diffraction. In all three compounds, the co-ordination polyhedra of lead(II) are formed by N atoms from two bipy molecules, O atoms of the substituent attached to the boron cage, and BH groups of the boron cage.
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Furqani, Firda, Lee Wah Lim i Toyohide Takeuchi. "One-pot Facile Preparation of Amino-functionalized Silica Hybrid Monoliths for Mixed-mode Chromatography". Journal of the Indonesian Chemical Society 2, nr 2 (30.12.2019): 81. http://dx.doi.org/10.34311/jics.2019.02.2.81.
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Silica hybrid monolithic columns were prepared using two precursors, in which organo-functionalized trialkoxysilanes are mixed with tetraalkoxysilanes. In this study, several types of amino-functionalized silica hybrid monolithic columns were prepared via single-step “one-pot” approach, and the amount of silica precursors, porogens, as well as the reaction conditions were optimized. The preparation was carried out by mixing the silica precursors, i.e. tetraethoxysilane (TEOS) or tetramethoxysilane (TMOS) with amino precursors such as aminopropyltrimethoxysilane (APTES), aminoethylaminopropyl-trimethoxysilane (AEAPTMS), and phenylaminopropyltrimethoxysilane (PAPTMS) in a porogenic solution. The chromatographic performance of these hybrid monolithic columns was optimized by investigating several parameters through the separation of inorganic anions (IO3-, BrO3-, Br-, NO2-, NO3-, I-, SCN-) and some polar compounds (thymine, thymidine, adenosine, adenine, uridine). Results showed that the silica hybrid monolithic columns could be operated at higher flow-rate that favors rapid separation. The run-to-run repeatability of Si-APTES and Si-PAPTMS hybrid monolithic columns were satisfactory with relative standard deviations (n = 5) of less than 8% for all the analyte anions.
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Tsujimoto, Yoshihiro, Yoshitaka Matsushita, Kazunari Yamaura i Tetsuo Uchikoshi. "High-pressure Synthesis of New layered Oxyhalide Perovskites". Acta Crystallographica Section A Foundations and Advances 70, a1 (5.08.2014): C762. http://dx.doi.org/10.1107/s2053273314092377.
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The development of transition metal oxides with perovskite-based structure has stimulated the search for mixed anion systems such as oxynitrides, oxyhalides and oxysulfides because incorporation of two different anions in one structure offers further opportunity to effectively induce chemical and physical properties that the pure oxides cannot possess. Such mixed anion phases, however, are difficult to be synthesized by a conventional high-temperature reaction. In this study, we have employed a high pressure technique to overcome this issue, and succeessfully synthesized a series of new layered oxhalide compounds. We present structural and magnetic properties of high-valent nickel oxyhalides Sr2NiO3X (X = F, Cl), and square-planar coordinated oxychlorides Sr2MO2Cl2 (Mn, Ni) and Ba2PdO2Cl2, isostructural with superconducting parent compund Ca2CuO2Cl2.
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Lehner, Anna J., i Caroline Röhr. "Kalium-Doppelsalze mit den gemischten Trisulfidometallat-Ionen [MoOS3]2- und [WOS3]2- / Potassium Double Salts with the Mixed Trisulfidometalate Ions [MoOS3]2- and [WOS3]2-". Zeitschrift für Naturforschung B 68, nr 7 (1.07.2013): 761–77. http://dx.doi.org/10.5560/znb.2013-3108.
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In the course of the synthesis of mixed oxidosulfido molybdates and tungstates by passing H2S gas through solutions of the oxido metalates, several new salts containing the metalates [MOS3]2- besides further anions (halides X-, hydrosulfide SH- or thiosulfate S2O2-3) were obtained as well-formed crystals. Their crystal structures have been determined using single crystal X-ray data. The salts containing SH- as the additional anion crystallize with a new structure type (orthorhombic, space group Pmn21, M=Mo=W, TM =20=-125 °C: a=957.7(2)/954.15(2), b=636.2(2)/636.19(1), c=812.4(2)/809.88(2) pm, Z =2, R1=0.0319=0.0185). The mixed sulfidomolybdate/ chloride K3[MoO1.25S2.75]Cl (orthorhombic, space group Pca21, a=1246.3(1), b=623.20(4), c=1230.44(8) pm, Z =4, R1=0.0472) is isotypic with the sulfidotungstate K3[WOS3]Cl, but contains 25% of the disulfido molybdate. The structures of the SH- and the Cl- salts are closely related: In both cases, the trisulfido metalates are overall coordinated by cuboctahedra of 12 K+ ions, and the small additional anions are centered in K+ octahedra. In this regard, the structures are both derivatives of the cubic perovskite (and thus the Cu3Au) type. This crystallographic group-subgroup relation is discussed in detail. Yellow hexagonal columns of the double salt K6[WOS3]2(S2O3) were obtained by the methanothermal decomposition of the disulfidotungstate K2[WO2S2]. It crystallizes with a new structure type (hexagonal, space group P63mc, a=983.78(8), c=1227.3(1) pm, Z =2, R1=0.0175). Like in the other mixed salts, the two crystallographically different [WOS3]2- anions exhibit an overall cuboctahedral coordination by 12 potassium cations. The smaller S2O2-3 anions are surrounded by nine K+ ions arranged in the form of two flat facesharing octahedra. Again similar to the mixed halides and hydrosulfides, the two K polyhedra around the anions, here present in a 2 : 1 ratio, are arranged in a space-filling packing, in this case related to the ht- BaMnO3 (and thus the Ni3Ti) structure type. According to their ‘double salt’ character, the Mo/W-O and Mo/W-S distances and the intramolecular vibrational frequencies of the tetrahedral moieties of the title compounds are similar between them and those in the pure potassium trisulfido metalates. This further becomes apparent from the additive nature of their molar volumes, which correspond to the sum of the volumes of the simple salts KCl, KSH or K2(S2O3) and K2[MoOS3].
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Kageyama, Keisuke, Yang Yang, Toki Kageyama, Kantaro Murayama, Kazuki Shitara, Takashi Saito, Hiroki Ubukata, Cédric Tassel, Akihide Kuwabara i Hiroshi Kageyama. "Kinetic Control of Anion Stoichiometry in Hexagonal BaTiO3". Inorganics 10, nr 6 (27.05.2022): 73. http://dx.doi.org/10.3390/inorganics10060073.
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The cubic oxyhydride perovskite BaTiO3−xHx, where the well-known ferroelectric oxide BaTiO3 is partially hydridized, exhibits a variety of functions such as being a catalyst and precursor for the synthesis of mixed-anion compounds by utilizing the labile nature of hydride anions. In this study, we present a hexagonal version, BaTi(O3−xHx) (x < 0.6) with the 6H-type structure, synthesized by a topochemical reaction using hydride reduction, unlike reported hexagonal oxyhydrides obtained under high pressure. The conversion of cubic BaTiO3 (150 nm) to the hexagonal phase by heat treatment at low temperature (950~1025 °C) using a Mg getter allows the introduction of large oxygen defects (BaTiO3−x; x − 0.28) while preventing the crystal growth of hexagonal BaTiO3, which has been accessible at high temperatures of ~1500 °C, contributing to the increase of the hydrogen content. Hydride anions in 6H-BaTiO3−xHx preferentially occupy face-sharing sites, as do other oxyhydrides.
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Atchekzaï, Jean, Bernard Bonnetot, Henri Mongeot, Sami Boufi i Bernard Frange. "The reaction of boron trichloride – tertiary amine adducts with pseudohalide salts under phase transfer catalysis conditions". Canadian Journal of Chemistry 70, nr 10 (1.10.1992): 2520–25. http://dx.doi.org/10.1139/v92-319.
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The reaction of boron trichloride – tertiary amine adducts D•BCl3 with pseudohalide salts MX was investigated in a homogeneous medium or in two-phase systems under liquid/liquid or solid/liquid phase transfer catalysis conditions (PTC) as a potential route to the adducts D•BX3 (X = NCS, NCO). Best results were obtained with solid/liquid PTC with tetraglyme as catalyst. By suitable choice of the tertiary amine, solvent, and stoichiometry, the symmetric compounds D•BX3 were thus prepared with good yields, the same reaction leading either to mixed species D•BX3-nCln (n = 1, 2; X = NCS, NCO) or to the tetrapseudohaloborate anions BX4− + (X = NCS, NCO). The mixed tetrahaloborates BX4-n Yn− could be obtained by exchange reaction from BX4− + BY4− (X = NCS, Y = F, Cl, Br) or from BY3 + Bu4NX (X = NCS; Y = F, Cl, Br; X = NCO; Y = F). All these compounds were characterized by 11B and, in one case, by 1H and 13C NMR. Pairwise additivity is observed for the 11B NMR chemical shifts.
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Coles, Martyn P., i Peter B. Hitchcock. "Bicyclic Guanidinates in Mono- and Di-Valent Metal Complexes, Including Group 1/2 and Group 1/12 Heterometallic Systems". Australian Journal of Chemistry 66, nr 10 (2013): 1124. http://dx.doi.org/10.1071/ch12560.
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Complexes containing mono-, di-, and mixed mono-/di-valent metal centres supported by the [hpp]– anion (hppH = 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine) are reported. Amine elimination from Mn(N{SiMe3}2)2 using the neutral guanidine is a clean route to the heteroleptic compound [Mn(hpp)(N{SiMe3}2)]2. Addition of 18-crown-6 to a solution of the hpp– potassium salt (hppK) enables the first potassium derivative of [hpp]– to be structurally analysed, showing that the crown ether restricts aggregation to afford a monometallic structure. Mixed lithium–magnesium and lithium–zinc compounds of general formula Li2M2(hpp)6 (M = Mg, Zn) have been characterised crystallographically showing the guanidinate anions to be present in two different coordination modes, bridging two- or four-metal centres. Spectroscopic measurements suggest a robust framework that is maintained in solution.
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Rawat, Ashima, i Ravindra Pandey. "Strain and Substrate-Induced Electronic Properties of Novel Mixed Anion-Based 2D ScHX2 (X = I/Br) Semiconductors". Nanomaterials 14, nr 17 (26.08.2024): 1390. http://dx.doi.org/10.3390/nano14171390.
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Exploration of compounds featuring multiple anions beyond the single-oxide ion, such as oxyhalides and oxyhydrides, offers an avenue for developing materials with the prospect of novel functionality. In this paper, we present the results for a mixed anion layered material, ScHX2 (X: Br, I) based on density functional theory. The result predicted the ScHX2 (X: Br, I) monolayers to be stable and semiconducting. Notably, the electronic and mechanical properties of the ScHX2 monolayers are comparable to well-established 2D materials like graphene and MoS2, rendering them highly suitable for electronic devices. Additionally, these monolayers exhibit an ability to adjust their band gaps and band edges in response to strain and substrate engineering, thereby influencing their photocatalytic applications.
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Antipov, Evgeny V., Nellie R. Khasanova i Stanislav S. Fedotov. "Perspectives on Li and transition metal fluoride phosphates as cathode materials for a new generation of Li-ion batteries". IUCrJ 2, nr 1 (1.01.2015): 85–94. http://dx.doi.org/10.1107/s205225251402329x.
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To satisfy the needs of rapidly growing applications, Li-ion batteries require further significant improvements of their key properties: specific energy and power, cyclability, safety and costs. The first generation of cathode materials for Li-ion batteries based on mixed oxides with either spinel or rock-salt derivatives has already been widely commercialized, but the potential to improve the performance of these materials further is almost exhausted. Li and transition metal inorganic compounds containing different polyanions are now considered as the most promising cathode materials for the next generation of Li-ion batteries. Further advances in cathode materials are considered to lie in combining different anions [such as (XO4)n−and F−] in the anion sublattice, which is expected to enhance the specific energy and power of these materials. This review focuses on recent advances related to the new class of cathode materials for Li-ion batteries containing phosphate and fluoride anions. Special attention is given to their crystal structures and the relationships between structure and properties, which are important for their possible practical applications.
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Baroud, Najah, Syarifa Wahidah Al Idrus i R. Rahmawati. "Characterization of methanol extract from Renggak (Amomum dealbatum Roxb) leaves and its application as an anion detector." Acta Chimica Asiana 7, nr 2 (14.12.2024): 534–40. https://doi.org/10.29303/aca.v7i2.192.
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Renggak (Amomum dealbatum Roxb) shows significant potential as a natural resource with applications in various fields, particularly in environmental sensing. This capability positions Renggak as a promising candidate for developing eco-friendly chemosensors, contributing to improved monitoring of these critical anions in the environment and health. Additionally, its diverse phytochemical profile suggests potential uses in medicinal applications, further enhancing its value as a multifaceted plant. This research focuses on the characterization of the methanol extract from Renggak (Amomum dealbatum Roxb) leaves, and it's potential to detect iodide and phosphate anions. The extraction process involved soaking dried renggak leaves in methanol for 72 hours. Afterwards, the solution was filtered and evaporated, resulting in a paste-like extract. The extract was characterized using FTIR and GC-MS techniques, followed by testing its performance as a chemosensor. The paste extract was dissolved in methanol and mixed with a saturated solution of iodide and phosphate salts for the anion detection test. Then, 3 mL of each anion solution was combined with the extract, and any changes in the solution were observed. FTIR analysis revealed the presence of OH groups and C=O double bonds in the methanol extract. GC-MS analysis identified 20 compounds, with hexadecanoic acid and 9-octadecenoic acid being the most abundant. The extract demonstrated fluorescent properties in the anion detection test, acting as a chemosensor. When exposed to a UV lamp at 250 nm, the solution emitted a green fluorescent glow, indicating the successful detection of anions. These findings suggest that the methanol extract of renggak leaves could serve as an effective fluorescent chemosensor for iodide and phosphate anions.
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Zhong, Kai-Long. "Tris(1,10-phenanthroline-κ2N,N′)iron(II) bis(2,4,5-tricarboxybenzoate) monohydrate and tris(2,2′-bipyridine-κ2N,N′)iron(II) 2,5-dicarboxybenzene-1,4-dicarboxylate–benzene-1,2,4,5-tetracarboxylic acid–water (1/1/2)". Acta Crystallographica Section C Crystal Structure Communications 68, nr 9 (18.08.2012): m259—m264. http://dx.doi.org/10.1107/s0108270112034567.
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The title compounds, tris(1,10-phenanthroline-κ2N,N′)iron(II) bis(2,4,5-tricarboxybenzoate) monohydrate, [Fe(C12H8N2)3](C10H5O8)2·H2O, (I), and tris(2,2′-bipyridine-κ2N,N′)iron(II) 2,5-dicarboxybenzene-1,4-dicarboxylate–benzene-1,2,4,5-tetracarboxylic acid–water (1/1/2), [Fe(C10H8N2)3](C10H4O8)·C10H6O8·2H2O, (II), were obtained during an attempt to synthesize a mixed-ligand complex of FeIIwith an N-containing ligand and benzene-1,2,4,5-tetracarboxylic acidviaa solvothermal reaction. In both mononuclear complexes, each FeIImetal ion is six-coordinated in a distorted octahedral manner by six N atoms from three chelating 1,10-phenanthroline or 2,2′-bipyridine ligands. In compound (I), the FeIIatom lies on a twofold axis in the space groupC2/c, whereas (II) crystallizes in the space groupP21/n. In both compounds, the uncoordinated carboxylate anions and water molecules are linked by typical O—H...O hydrogen bonds, generating extensive three-dimensional hydrogen-bond networks which surround the cations.
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Govindasamy, Rathika, Sathiyapriya Thirumalaisamy, Kohila chandran, Manikandan Dhayalan i Mika Sillanpaa. "Improved corrosion inhibition by heterocyclic compounds on mild steel in acid medium". Corrosion Reviews 40, nr 2 (15.02.2022): 137–48. http://dx.doi.org/10.1515/corrrev-2021-0045.
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Abstract A detailed comparative study on inhibitive behaviour against corrosion of mild steel in 1N H2SO4 IN HCl for the Schiff bases 2,6-diphenyl-3-methyl azinan-4-one (D3MA) (S1), 2,6-diphenyl-3-methyl azinan-4-one semicarbazone (D3MAS) (S2), 2,6-diphenyl azinan-4-one (DA) (S3) and 2,6-diphenylazinan-4-one semicarbazone (DAS) (S4) was investigated using gravimetric and potentiodynamic polarisation methods. The thermodynamic parameters for the mild steel corrosion and the synergistic behaviour of the inhibitors in the presence of anions and cations were determined and discussed. It was found that the adsorption of the inhibitors on the mild steel surface obeyed Langmuir adsorption isotherm. Electro chemical studies revealed that all the four inhibitors are of mixed type. We proved that the semicarbazones (Schiff bases S2b and S4) with additional O and N are more effective corrosion inhibitors than their parent keto-amines. As a whole from all the proposed studies it is proved that the explored Schiff’s bases work as a very efficient corrosion inhibitor for mild steel in both the acidic medium.
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Mishchenko, Artem, Elena Trunova i Tamara Makotryk. "THERMODESTRUCTION OF Lа(III) COORDINATION COMPOUNDS WITH ALIPHATIC β-KETOESTERS". Ukrainian Chemistry Journal 87, nr 8 (24.09.2021): 99–115. http://dx.doi.org/10.33609/2708-129x.87.08.2021.99-115.
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Mono- and mixed-ligand complexes of La (III) with aliphatic β-ketoesters were synthesized in the solid state. The complexes have the general formulas LаL2OH·H2O (L=meacac, etacac, alacac) and La(meacac)2X·nCH3OH(X = NO3, CH3COO; n = 1, 2). Their composition, structure, and thermal properties were established by chemical and thermal analysis, IR spectroscopy. It is shown that β-ketoesters are coordinated to the La (III) ion bidentate-cyclically into monoligand hydroxocomplexes. Ligand complexes with methylacetoacetate have an oligomeric structure. They consist of cationic fragments [La(meacac)2]+ with bridged connection of the nitrate or acetate anions.
The thermal destructions of LaL2OH·H2O (L = meacac, etacac, alacac), La(meacac)2NO3· 2CH3OH and La(meacac)2(CH3COO)·CH3OH were studied for the first time in the helium dynamic atmosphere by TGA-MS in the temperature range of 25–900 °C. Depending on the ligand, dehydratation of the hydroxo-complexes takes place in the 120–180 (meacac), 120–190 (etacac) or 110–160 °C (alacac) temperature range, and the mass loss corresponds with the detachment of one water molecule. Decomposition of mixed-ligand complexes starts with the detachment of methanol in the 60–100 °C range. For La(meacac)2NO3·2CH3OH the decomposition process is attended with oxidation of methanol to carbon dioxide due to reduction of the nitrate-ion to nitrogen dioxide. Further heating to 300–400 °C leads to destruction of organic parts of the complexes attended with the release of low-molecular oxygen-containing organic compounds (aldehydes, ketones, alcohols), carbon dioxide and water. At ~500 °C all the La(III) complexes under study totally decompose, yielding the oxycarbonate La2O2CO3, which was fixed by IR spectroscopy. Under further heating to 850 °С oxycarbonate gradually decomposes to La2O3 liberating CO2.
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Shmelev, Maxim A., Anastasia A. Levina, Aleksandr S. Chistyakov, Evgeniya A. Varaksina, Julia K. Voronina, Galina A. Razgonyaeva, Il'ya Viktorovich Taidakov, Alexey A. Sidorov i Igor Leonidovich Eremenko. "Influence of the anion ratio in the composition of mixed benzoate/pentafluorobenzoate complexes of europium on the structure and photoluminescent properties". Mendeleev Communications 35, nr 1 (2025): 35–38. https://doi.org/10.71267/mencom.7566.
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Mixed carboxylate benzoate (bz)/pentafluorobenzoate (pfb) complexes with different ratios of pfb and bz anions in the {Eu(EtOH)<sub>2</sub>(pfb)(bz)<sub>2</sub>}<sub>n</sub> and {Eu(EtOH)(pfb)<sub>2</sub>(bz)}<sub>n</sub> compositions were obtained and structurally characterized. Changes in the pfb/bz ratio lead to changes in the geometry of the polymer chains and the lanthanide polyhedron, as well as to a rearrangement of the system of non-covalent interactions, which also affects the photoluminescent properties. The synthesized compounds were characterized by X-ray diffraction study, IR spectroscopy and CHN analysis; non-covalent interactions were analyzed using Hirshfeld surface analysis.
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Dzhurinskii, B. F., i G. V. Lysanova. "ChemInform Abstract: Lanthanide Compounds with Mixed Oxo Anions: Synthesis, Structure, and Existence Boundaries in the Series from Lathanum to Lutetium." ChemInform 30, nr 13 (16.06.2010): no. http://dx.doi.org/10.1002/chin.199913028.
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Martsinko, E. E., I. I. Seifullina, E. A. Chebanenko i A. G. Pesaroglo. "MIXED-LIGAND GERMANIUM–LANTHANIDE COMPLEXES WITH 1-HYDROXYETHYLIDENEDIPHOSPHONIC ACID AND 2,2’-BIPYRIDINE". Odesa National University Herald. Chemistry 27, nr 3(83) (19.01.2023): 53–62. http://dx.doi.org/10.18524/2304-0947.2022.3(83).268690.
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There were developed the novel methods for the synthesis of six mixed- metal and mixed-ligand complexes of germanium and rare earth metals (Pr, Nd, Dy, Ho, Tm, Lu) with 1-hydroxyethylidenediphosphonic acid and 2,2´-bipyridine. The compounds have been characterized using various research methods: elemental analysis, mass spectrometry, electrical conductivity, thermogravimetry, IR spectroscopy. It has proved that all complexes are crystal hydrates, belong to heterometallic mixed ligand compounds [Ln(H2O)4(bipy)2]2 [Ge(m-hedp) (m- OH)]6⸱nH2O, Ln=Pr (1); Nd (2); Dy (3); Ho (4); Tm (5); Lu (6); n = 22 (1, 2), 21 (3), 20 (4, 5), 19 (6). Their formation occurs due to the electrostatic interaction of complex cations [Ln(H2O)4(bipy)2]3+ with hexanuclear anions [Ge(m-hedp)(m- OH)]66-. According to the results of measuring the electrical conductivity of dimethylformamide solutions 1–6, it has been established that they belong to triionic electrolytes: λ (in Ohm-1∙сm2∙mol-1) for 1 = 131,3; 2 = 138,8; 3 = 145,8; 4 = 151,1; 5 = 158,3; 6 = 162,7. The cation-anionic type of complexes 1–6 has been confirmed as a result of the analysis of their mass spectrum. The analysis of the mass spectrum showed that the main decomposition direction of the complex is related to the formation of the complex cation fragment [Ln(H2O)4(bipy)2]3+, which corresponds to the most intense peak (m/z = 136, I = 55%). The thermal decomposition of compounds 1–6 includes dehydration, deaquatation, oxidative thermal destruction and the formation of final products as a mixture of Ln2O3 and GeP2O7. On the DTA curves in the interval 70–200 °C the first endothermic effect can be traced, which is accompanied by the removal of a certain number of crystallization and coordination water molecules into the gas phase. Absorption bands of the P-O bond have been detected at ~1053 and ~970 сm-1, that indicates the presence of the fully deprotonated PO32- groups in the composition of complexes. Furthermore, n(OH), ν(Ge–O), d(Ge–OH) bands characteristic for all the previously synthesized compounds with [Ge6(m-OH)6(m-hedp)6]6- anion have been detected in the IR spectra of 1–6. A set of the bands usual for the aromatic molecules n(C–C), das(CH3), ds(CH3), n(Сar=N) has been assigned with 2,2`-bipyridine in the structure of all compounds.
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Vassilyeva, Olga Yu, Elena A. Buvaylo, Vladimir N. Kokozay i Brian W. Skelton. "Organic–inorganic hybrid mixed-halide ZnII and CdII tetrahalometallates with the 2-methylimidazo[1,5-a]pyridinium cation". Acta Crystallographica Section E Crystallographic Communications 78, nr 4 (8.03.2022): 359–64. http://dx.doi.org/10.1107/s2056989022002420.
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Three isomorphous 0-D hybrid salts, namely, 2-methylimidazo[1,5-a]pyridinium trichloridoiodidozincate(II), (C8H9N2)2[ZnCl3.19I0.81] or [L]2[ZnCl3.19I0.81], (I), 2-methylimidazo[1,5-a]pyridinium dibromidodichloridocadmate(II), (C8H9N2)2[CdBr2.42Cl1.58] or [L]2[CdBr2.42Cl1.58], (II), and 2-methylimidazo[1,5-a]pyridinium trichloridoiodidocadmate(II), (C8H9N2)2[CdCl3.90I0.10] or [L]2[CdCl3.90I0.10], (III), are assembled from discrete 2-methylimidazo[1,5-a]pyridinium cations, L +, and mixed-halide tetrahalometallate anions. In the three structures, there are two crystallographically non-equivalent cations that were modelled as being rotationally disordered by 180°. In the lattices of the three compounds, a disordered state exists involving partial substitution of Cl by I for sites 2–4 in (I), Br by Cl for all four sites in (II) and Cl by I for site 2 in (III). In the solid state, the organic and inorganic sheets alternate parallel to the bc plane in a pseudo-layered arrangement. In the organic layer, pairs of centrosymmetically related trans-oriented cations form π-bonded chains. The adjacent tetrahalometallate anions in the inorganic layer show no connectivity with the shortest M...M separations being greater than 7 Å. A variety of C—H...X—M (X = Cl, Br, I) contacts between the organic and inorganic counterparts provide additional structural stabilization. The title structures are isomorphous with the previously reported structures of the chloride analogues, [L]2[ZnCl4] and [L]2[CdCl4].
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Frisch, Gero, i Caroline Röhr. "A5Fe3O6] (A = Rb, Cs), Cs[FeO2] und Cs8[Fe2O7]: Neue Oxoferrate der schweren Alkalimetalle / A5Fe3O6] (A = Rb, Cs), Cs[FeO2] and Cs8[Fe2O7]: New Oxoferrates of the Heavy Alkaline Metals". Zeitschrift für Naturforschung B 59, nr 7 (1.07.2004): 771–81. http://dx.doi.org/10.1515/znb-2004-0705.
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The title compounds were synthesized at a temperature of 775 K via reaction of Fe2O3 with elemental cesium and rubidium alone or in combination with their hyperoxides AO2 where required by stoichiometry. The structures of the dark-red crystals have been determined by single crystal x-ray diffraction (Cs[FeO2]: cubic, space group Fd3m, a = 839.2(2) pm, Z = 8, R1 = 0.0547 and A5[Fe3O6] (A = Cs: orthorhombic, space group P212121, a = 861.8(2), b = 870.7(2), c = 1658.7(3) pm, Z = 4, R1 = 0.0617 and A = Rb: tetragonal, space group I4̅2d, a = 862.01(8), c= 1504.7(2) pm, Z =4, R1= 0.0334). These three compounds contain three-dimensional networks [FeO2], in the case of the ideal stuffed cristobalite composed of corner-sharing tetrahedra [FeO4/2], in the case of the new mixed valence compounds A5[Fe3O6] formed by corner-sharing of tetrahedra [FeIIIO4/2] and triangles [FeIIOO2/2] in a 1:2 ratio. The crystal structure of the cation rich compound Cs8[Fe2O7] (monoclinic, space group P21/c, a = 722.32(12), b = 1789.0(3), c = 733.88(12) pm, β =118.976(3)°, Z = 4, R1=0.0287) exhibits di-ferrate anions [Fe2O7]6− composed of two cornersharing [FeIIIO4] tetrahedra with a linear Fe-O-Fe bridge.
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Palamarchuk, M. S., E. A. Shelestyuk, E. A. Tokar’ i A. M. Egorin. "Sorption of Complex Co(II)-EDTA by Anion Exchange Resin AB-17-8 from Model Deactivating Solutions Containing Fe(III)-EDTA". Ecology and Industry of Russia 24, nr 6 (17.06.2020): 20–23. http://dx.doi.org/10.18412/1816-0395-2020-6-20-23.
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The results of studies of the sorption of EDTA complexes with ions Co(II) and Fe(III) on anion exchange resin AB-17-8 used in mixed filters of special water treatment apparatus of NPP are presented. The character of the sorption process of complexes Co(II)-EDTA and Fe(III)-EDTA in acidic media depending on the pH and salt background of solutions simulating deactivating solutions formed after the dissolution of iron oxide compounds containing cobalt radionuclides was studied. It has been shown that upon deactivation of spent ion-exchanged resins with acid solutions of EDTA salts, the secondary sorption of EDTA complexes with cobalt radionuclides on anion exchange resin can be reduced by lowering the pH of the deactivating solutions and increasing the concentration of competing inorganic anions, with no noticeable competing effects of the complexes Fe(III)-EDTA.
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Pauwels, Damien, Alain Demourgues, Hervé Laronze, Pierre Gravereau, François Guillen, Olivier Isnard i Alain Tressaud. "Structural features of new rare earth-based mixed anions (O, S, F) compounds: relationships between optical absorption and rare earth environment". Solid State Sciences 4, nr 11-12 (listopad 2002): 1471–79. http://dx.doi.org/10.1016/s1293-2558(02)00038-9.
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Androš, Lidija, Dubravka Matković-Čalogović i Pavica Planinić. "A series of compounds containing various (oxalato)tantalate(v) complex anions – synthesis, properties and the mixed-metal oxide formation via thermal decomposition". CrystEngComm 15, nr 3 (2013): 533–43. http://dx.doi.org/10.1039/c2ce26391b.
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Kucha, H., i E. F. Stumpfl. "Thiosulphates as precursors of banded sphalerite and pyrite at Bleiberg, Austria". Mineralogical Magazine 56, nr 383 (czerwiec 1992): 165–72. http://dx.doi.org/10.1180/minmag.1992.056.383.03.
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AbstractBanded sphalerite from Bleiberg, Austria, contains ubiquitous relics of Fe-thiosulphates and Fesulphites up to 50 μm in size. Zn, Pb, Ni and As form admixtures ranging from a few to 12 wt.% in these compounds. It is suggested that banded sphalerite is formed by a replacement of banded thiosulphate and thiosulphite precursors. This suggestion is supported by a significant admixture of Fe 0.41-8.20 wt.%) and the presence of goethite inclusions in banded sphalerite. In contrast, crystalline ZnS intergrown with the banded variety is Ni-free and contains only 0.06-0.14 wt.% Fe.Banded pyrite contains inclusions of Fe-thiosulphate up to 200 μm in size. These thiosulphates contain (wt.%): 0.09-1.92 Zn, and 2.67−4.02 Pb. Pyrite formed by replacement (breakdown) of Fethiosulphate precursors contains 3.69-3.83 wt.% Pb.It is suggested that banded sulphides precipitate from solutions carrying sulphur with mixed valances, and crystalline sulphides grow from solutions where the dominant dissolved sulphur is in the form of sulphidic anions.
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Béres, Kende Attila, Zsolt Dürvanger, Zoltán Homonnay, Laura Bereczki, Berta Barta Holló, Attila Farkas, Vladimir M. Petruševski i László Kótai. "Insight into the Structure and Redox Chemistry of [Carbonatotetraamminecobalt(III)] Permanganate and Its Monohydrate as Co-Mn-Oxide Catalyst Precursors of the Fischer-Tropsch Synthesis". Inorganics 12, nr 4 (22.03.2024): 94. http://dx.doi.org/10.3390/inorganics12040094.
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[Carbonatotetraamminecobalt(III)] permanganate monohydrate was synthesized first in the metathesis reaction of [Co(NH3)4CO3]NO3 and NaMnO4 in aqueous solution. Its thermal dehydration at 100 °C resulted in phase-pure [Co(NH3)4CO3]MnO4 (compound 1). Compounds 1 and 2 (i.e., the hydrated form) were studied with IR, far-IR, and low-temperature Raman spectroscopies, and their vibrational modes were assigned. The lattice parameters were determined by powder X-ray diffraction (PXRD) and single crystal X-ray diffraction (SXRD) methods for the triclinic and orthorhombic compounds 1 and 2, respectively. The detailed structure of compound 2 was determined, and the role of hydrogen bonds in the structural motifs was clarified. UV studies on compounds 1 and 2 showed the distortion of the octahedral geometry of the complex cation during dehydration because of the partial loss of the hydrogen bonds between the crystal water and the ligands of the complex cation. The thermal decomposition consists of a solid phase quasi-intramolecular redox reaction between the ammonia ligands and permanganate anions with the formation of ammonia oxidation products (H2O, NO, N2O, and CO2). The solid phase reaction product is amorphous cobalt manganese oxide containing ammonium, carbonate (and nitrate) anions. The temperature-controlled thermal decomposition of compound 2 in toluene at 110 °C showed that one of the decomposition intermediates is ammonium nitrate. The decomposition intermediates are transformed into Co1.5Mn1.5O4 spinel with MnCo2O4 structure upon further heating. Solid compound 2 gave the spinel at 500 °C both in an inert and air atmosphere, whereas the sample pre-treated in toluene at 110 °C without and with the removal of ammonium nitrate by aqueous washing, gave the spinel already at 300 and 400 °C, respectively. The molten NH4NO3 is a medium to start spinel crystallization, but its decomposition stops further crystal growth of the spinel phase. By this procedure, the particle size of the spinel product as low as ~4.0 nm could be achieved for the treatments at 300 and 400 °C, and it increased only to 5.7 nm at 500 °C. The nano-sized mixed cobalt manganese oxides are potential candidates as Fischer-Tropsch catalysts.
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Hoekstra, Ryan M., Yen-Ting Chen, Matthew D. Kiesz, João P. Telo, Rachel M. Stephenson, Stephen F. Nelsen i Jeffrey I. Zink. "Resonance Raman spectroscopic study of solvent-dependent coexistence of localized and delocalized dinitroaromatic radical anions". Canadian Journal of Chemistry 92, nr 10 (październik 2014): 940–47. http://dx.doi.org/10.1139/cjc-2014-0058.
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Optical absorption spectra of three dinitroaromatic radical anions, 2,7-dinitro-9,9-dimethylfluorene (1•−), 4,4′-dinitrobiphenyl (2•−), and 4,4′-dinitrotolane (3•−) in solvents THF, HMPA, and MeCN show both an unresolved broad band characteristic of charge-localized mixed valence species (Robin-Day classification Class II), and a vibronically structured band of the delocalized species (Class III). With decreasing solvent reorganization energy, a greater portion of the compounds become charge-delocalized. In particular, 1•− with the greatest coupling, is almost entirely composed of the delocalized species in all solvents. An intense Raman mode is used to identify the charge-bearing unit as the nitrobenzene moiety. Resonance Raman profiles are utilized to gain detailed information of vibrational modes. The out-of-phase ring lengthening stretch mode is observed to be enhanced at higher excitation energies, corresponding to the absorption band of the Class II species, while the in-phase ring lengthening stretch mode, a totally symmetric vibration, is most strongly enhanced in the absorption region of the Class III species. Resonance Raman profiles support the solvent-dependent coexistence of Class II and Class III molecules of the same chemical composition.
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Shafei, Gamal M. S. El. "Change of Structural and Adsorption Properties Due to Isomorphous Substitution in Hydrotalcite-like Materials". Adsorption Science & Technology 20, nr 8 (październik 2002): 767–86. http://dx.doi.org/10.1260/026361702321104264.
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Samples of hydrotalcite-like compounds with the general formula [M2+1-xM3+x(OH)2]x+•Ax–•nH2O were prepared via coprecipitation through the addition of NaOH to mixed chloride salt solutions. On maintaining the M2+/M3+ ratio equal to three, it was possible to effect isomorphous substitution. This led to the preparation of different compounds which could be compared to the parent material in which M2+ = Ni and M3+ = Al. Other divalent cations used were Mg2+ and Zn2+ with Cr3+ and Fe3+ being employed as trivalent cations. The ratio between cations of the same charge was unity in all the isomorphously substituted samples and substitution was conducted for one oxidation state only at a time. Hence, all samples contained a maximum of three different cations. The charge compensating anion in the interlayers, A, was identified as mainly CO32– with the co-existence of Cl− anions to different extents. The structural and textural properties developed as a result of the substitutions effected were studied by XRD, IR, DTA, acid–base titration and mercury porosimetry measurements. Various samples were used for the adsorption of 4-chlorophenol to examine the effects on the adsorption properties arising from isomorphous substitution. The major effect having a marked influence on the adsorption properties arose from the nature of the compensating anion in the interlayers. Different tendencies of different cations to be accommodated in the layer structure resulted in different interlayer spaces and variable conformations of the charge compensating anion. In all cases, at low equilibrium concentrations, the adsorption of 4-chlorophenol (pH = 11) occurred at the edges of the layer structure accompanied by Cl−/OH− exchange. The increasing order in the amount of 4-chlorophenol adsorbed was matched by an increasing order in the interlayer space due to substitution. At higher values of the equilibrium concentration, the adsorption of both phenolate and OH− anions decreased. This was because such adsorption into the interlayer space to replace the CO2– anion was diffusion-controlled, making the process improbable at high pH values.
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Kussainova, Bakytgul, Gaukhar Tazhkenova, Ivan Kazarinov, Marina Burashnikova, Aisha Nurlybayeva, Gulnaziya Seitbekova, Saule Kantarbayeva i in. "Adsorption of Bichromate and Arsenate Anions by a Sorbent Based on Bentonite Clay Modified with Polyhydroxocations of Iron and Aluminum by the “Co-Precipitation” Method". Molecules 29, nr 15 (5.08.2024): 3709. http://dx.doi.org/10.3390/molecules29153709.
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The physicochemical properties of natural bentonite and its sorbents were studied. It has been established the modification of natural bentonites using polyhydroxoxides of iron (III) (mod.1_Fe_5-c) and aluminum (III) (mod.1_Al_5-c) by the “co-precipitation” method led to changes in their chemical composition, structure, and sorption properties. It was shown that modified sorbents based on natural bentonite are finely porous (nanostructured) objects with a predominance of pores of 1.5–8.0 nm in size. The modification of bentonite with iron (III) and aluminum compounds by the “co-precipitation” method also leads to an increase in the sorption capacity of the obtained sorbents with respect to bichromate and arsenate anions. A kinetic analysis showed that, at the initial stage, the sorption process was controlled by an external diffusion factor, that is, the diffusion of the sorbent from the solution to the liquid film on the surface of the sorbent. The sorption process then began to proceed in a mixed diffusion mode when it limited both the external diffusion factor and the intra-diffusion factor (diffusion of the sorbent to the active centers through the system of pores and capillaries). To clarify the contribution of the chemical stage to the rate of adsorption of bichromate and arsenate anions by the sorbents under study, kinetic curves were processed using equations of chemical kinetics (pseudo-first-order, pseudo-second-order, and Elovich models). It was found that the adsorption of the studied anions by the modified sorbents based on natural bentonite was best described by a pseudo-second-order kinetic model. The high value of the correlation coefficient for the Elovich model (R2 > 0.9) allows us to conclude that there are structural disorders in the porous system of the studied sorbents, and their surfaces can be considered heterogeneous. Considering that heterogeneous processes occur on the surface of the sorbent, it is natural that all surface properties (structure, chemical composition of the surface layer, etc.) play an important role in anion adsorption.
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Baranets, Sviatoslav, Gregory M. Darone i Svilen Bobev. "Structural diversity among multinary pnictide oxides: a minireview focused on semiconducting and superconducting heteroanionic materials". Zeitschrift für Kristallographie - Crystalline Materials 237, nr 1-3 (8.02.2022): 1–26. http://dx.doi.org/10.1515/zkri-2021-2079.
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Abstract Incorporating different anions with varied ionic sizes and charges is a rapidly growing approach to bring out unusual physical properties among various classes of solid-state materials, pnictides and chalcogenides in particular. This minireview is focused on hetero-anionic materials based on the pnictogens, which have been demonstrated to offer an impressive diversity of crystal chemistry and electronic structures. In addition, many pnictide oxides or oxypnictides, over the course of the last decade, have been shown to exhibit a broad spectrum of superconducting, magnetic, and semiconducting properties. However, the structural diversity of the mixed-anion materials is far greater than the several known structure types, or their variants, of the well-known layered superconductive materials. Therefore, with this treatise, we aim to provide a comprehensive overview of the crystal chemistry of pnictide oxides by recounting almost 40 different structures of such ternary and multinary compounds. In addition to the structural aspects, we also highlight some of the challenges associated with the synthesis, and briefly summarize reported, to date, physical properties of this remarkable class of solids.
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Chen, Shuai, Zexu Xue, Nan Gao, Xiaomei Yang i Ling Zang. "Perylene Diimide-Based Fluorescent and Colorimetric Sensors for Environmental Detection". Sensors 20, nr 3 (9.02.2020): 917. http://dx.doi.org/10.3390/s20030917.
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Perylene tetracarboxylic diimide (PDI) and its derivatives exhibit excellent thermal, chemical and optical stability, strong electron affinity, strong visible-light absorption and unique fluorescence on/off features. The combination of these features makes PDIs ideal molecular frameworks for development in a broad range of sensors for detecting environmental pollutants such as heavy metal ions (e.g., Cu2+, Cd2+, Hg2+, Pd2+, etc.), inorganic anions (e.g., F−, ClO4−, PO4−, etc.), as well as poisonous organic compounds such as nitriles, amines, nitroaromatics, benzene homologues, etc. In this review, we provide a comprehensive overview of the recent advance in research and development of PDI-based fluorescent sensors, as well as related colorimetric and multi-mode sensor systems, for environmental detection in aqueous, organic or mixed solutions. The molecular design of PDIs and structural optimization of the sensor system (regarding both sensitivity and selectivity) in response to varying analytes are discussed in detail. At the end, a perspective summary is provided covering both the key challenges and potential solutions for the future development of PDI-based optical sensors.
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Hernández-Fernández, Adrián, Eduardo Iniesta-López, Yolanda Garrido, Ioannis A. Ieropoulos i Francisco J. Hernández-Fernández. "Microbial Fuel Cell Using a Novel Ionic-Liquid-Type Membrane-Cathode Assembly with Heterotrophic Anodic Denitrification for Slurry Treatment". Sustainability 15, nr 20 (12.10.2023): 14817. http://dx.doi.org/10.3390/su152014817.
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In this paper, microbial fuel cell technology with heterotrophic anodic denitrification, based on a new membrane-cathode assembly, was tested for slurry treatment and bioenergy production. Slurry is used due to its high chemical oxygen demand and a high content of nutrient compounds of nitrogen which can contaminate soil and water. The new membrane-cathode assembly systems were based on different ammonium and phosphonium cations combined with chloride, bistriflimide, phosphate, and phosphinate anions and a non-noble catalyst composed of copper and cobalt mixed-valence oxides. The influence of ionic liquids on the catalytic membrane was studied. The best membrane-cathode assembly was based on the ionic liquid catalyst [MTOA+][Cl−]-CoCu which achieved 65% of the energy reached with the Pt-Nafion® system. The [MTOA+][Cl−]-CoCu system improved the water purification parameter, reducing the COD by up to 35%, the concentration of nitrates by up to 26%, and the organic nitrogen by up to 70% during the experiments. This novel membrane-cathode system allows for easier manufacturing, lower costs, and simpler catalysts than conventionally used in microbial fuel cells.
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Dore, Elisabetta, Franco Frau i Rosa Cidu. "Antimonate Removal from Polluted Mining Water by Calcined Layered Double Hydroxides". Crystals 9, nr 8 (6.08.2019): 410. http://dx.doi.org/10.3390/cryst9080410.
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Calcined layered double hydroxides (LDHs) can be used to remove Sb(V), in the Sb(OH)6− form, from aqueous solutions. Sorption batch experiments showed that the mixed MgAlFe oxides, obtained from calcined hydrotalcite-like compound (3HT-cal), removed Sb(OH)6− through the formation of a non-LDH brandholzite-like compound, whereas the mixed ZnAl oxides, resulting from calcined zaccagnaite-like compound (2ZC-cal), trapped Sb(OH)6− in the interlayer during the formation of a Sb(V)-bearing LDH (the zincalstibite-like compound). The competition effect of coexistent anions on Sb(OH)6− removal was HAsO42− >> HCO3− ≥ SO42− for 2ZC-cal and HAsO42− >> HCO3− >> SO42− for 3HT-cal. Considering the importance of assessing the practical use of calcined LDHs, batch experiments were also carried out with a slag drainage affected by serious Sb(V) pollution (Sb = 9900 μg/L) sampled at the abandoned Su Suergiu mine (Sardinia, Italy). Results showed that, due to the complex chemical composition of the slag drainage, dissolved Sb(OH)6− was removed by intercalation in the interlayer of carbonate LDHs rather than through the formation of brandholzite-like or zincalstibite-like compounds. Both 2ZC-cal and 3HT-cal efficiently removed very high percentages (up to 90–99%) of Sb(V) from the Su Suergiu mine drainage, and thus can have a potential application for real polluted waters.
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Bilov, V. V., V. I. Markov i V. V. Shipilo. "Hydroamination of n-butanol on Cu-containing anion-modified catalysts". Voprosy Khimii i Khimicheskoi Tekhnologii, nr 1 (marzec 2023): 50–55. http://dx.doi.org/10.32434/0321-4095-2023-146-1-50-55.
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The purpose of the work is to establish the relationship between the composition of new Cu-containing anion-modified compositions and their catalytic potential in the synthesis of dibutylamine, which is an important intermediate for the production of such significant products as medicines, insecticides, vulcanization accelerators for rubber compounds, multifunctional corrosion inhibitors, etc. Composite materials were prepared by thermal decomposition of a copper-ammonia-carbonate solution in the presence of chromate, molybdate, aluminum tungstate, aluminum metahydroxide, and lanthanum carbonate salts. The active state of the new catalysts was formed under the conditions of low-temperature heat treatment (2500C) and reduction (2400C), which ensure incomplete removal of modifying OH– and СО32– anions. The study of the catalytic efficiency of new samples in the process of vapor-phase hydroamination of n-butanol was carried out in a flow reactor at the n-butanol:ammonia:hydrogen molar ratio equal to 1.0:2.0:6.0, an alcohol load of 0.4 h–1 and temperatures of 200–2400C. Among the catalysts tested, the sample whose precursor was a mixed "compound" salt hydroxocarbonate copper-aluminum chromate showed the highest performance as follows: alcohol conversion and selectivity to the target dibutylamine of 86.3% and 82.7%, respectively (at 2200C). The least active was the sample, the precursor of which was a mixed "compound" salt hydroxocarbonate copper-lanthanum carbonate. Factors that can affect the catalytic efficiency of new materials were analyzed.
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Domonov, Denis P., i S. I. Pechenyuk. "Thermal decomposition of double complex compounds of 3D metals." Herald of Kola Science Centre of the RAS 12, nr 3-2020 (10.10.2020): 5–15. http://dx.doi.org/10.37614/2307-5228.2020.12.3.001.
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The paper is devoted to the study of thermolysis of double complex compounds (DCС) of metalsin the I transition series. 30 DCСwith various combinations of metal-central atoms (Co-Fe, Cu-Fe, Ni-Fe Cr-Fe, Cr-Co,) and ligands (ammonia, urea (ur), ethylenediamine (en), 1,3-diaminopropane (tn), cyanide, oxalate and nitrite anions) were synthesized and characterized. A complete study of the thermal proper-ties of these DCCs in three atmospheres was carried out: oxidizing (air), inert (Ar, N2, partly He) and re-ducing (H2), in the temperature range of 20–1000°Cand at constant heating rate of 10°C/min. The solid and gaseous thermolysis products were studied. In the air solid thermolysis products are represented by mixtures of central ions oxides or mixed oxides of the MIMII2O4type. The main gaseous products of thermolysis underthe temperature below 300°Cinclude NH3, HNCO (for urea DCС) and HCN (for cya-nocomplexes), and above 300°C —СО2. In addition, undecomposed ligands, CO, nitrogen oxides and probably nitrogen are presented in the gas phase. Thermolysis of the studied DCCgoesin the most com-plex way in inert atmospheres. Solid thermolysis products are heterogeneous mixtures of metals (Cu, Fe), solid solutions of CoxFe1-x, Ni3Fe intermetallic compounds, oxides, carbides and nitrides of central ions and amorphous carbon; the content of the latter reaches 58% of the initial content in the complex. The gaseous products of thermolysis include the same compounds, except for CO2, as in the atmosphere of air, but also in different ratios. In an H2atmosphere, all studied DCCs, except Cr-containing ones, are re-duced to the sum of central ions —Cu + Fe or solid solutions Co-Fe and Ni-Fe, practically free of carbon. Gaseous products are the same as in an inert atmosphere, butan increased yield of NH3and a reduced yield of CO2and/or HCN speak in favor of partial hydrogenation of the ligands to hydrocarbons. A review of the catalytic properties of solid products of DCC thermolysis (~170 samples) showed that about 1/3 of themare active in model reactions (catalytic decomposition of hydrogen peroxide, thermal decomposi-tion of ammonium perchlorate).
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Diamant, Viktor. "NOVEL NON-AQUEOUS ELECTROLYTES BASED ON COORDINATION BORON COMPOUNDS". Ukrainian Chemistry Journal 87, nr 3 (23.04.2021): 41–60. http://dx.doi.org/10.33609/2708-129x.87.03.2021.41-60.
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The review provides a classification of electrolytes for modern chemical power sources, supercapacitors, sodium and lithium-ion batteries depending on changes in the physicochemical properties of salts and the products of their interaction with the solvent. A comparative analysis of physicochemical properties of salts depending on the structure of the cation and anion, and the influence of these properties on the properties of final solutions of electrolytes on the example of different classes of ionic liquids and chelatoborates of alkali metals and ammonium was conducted. The dependence of the physicochemical properties of electrolytes (solubility, electrical conductivity of solutions and the range of potentials of electrochemical stability) on the nature of the chelate ligand, electron donor and electroacceptor substituents in the bis (chelate) borate anion is analyzed. The electrical conductivity of salt solutions and ranges of potentials of electrochemical stability of the corresponding electrolytes containing other anions and used for a long time in chemical current sources are carried out. The advantages and disadvantages of using liquid electrolytes compared to solid and polymer electrolytes in terms of similarity of their structures have been detected. It is shown that the nature of the chelate ligand, electro-donor and electro-acceptor substituents in the bis (chelato) borate anion is an important factor in regulating the interaction with aprotic dipolar solvents. Mixed salts with two different chelate ligands typically combine the best characteristics of the corresponding monochelate compounds, but the methods for their preparation and purification are technologically significantly more complex compared to monochelate compounds. The analysis of the mechanism of formation of a protective film on a surface of electrode materials, dependence of potential on its formation and on the chemical nature of ligands is made. It is noted that bis (chelato) borate salts are more environmentally friendly compared to fluorine-containing complex salts. Emphasis is placed on the physicochemical properties of solutions of the most promising chelatoborate salts for use in lithium and sodium ion batteries, supercapacitors and electrolytic capacitors, and it is shown that bis (oxalate) borates and bis (salicylate gold) borates occupy ) borates in terms of electrical conductivity, solubility and potential range of electrochemical stability.