Sensing Properties of NH2-MIL-101 Series for Specific Amino Acids via Turn-On Fluorescence

Metal–organic frameworks (MOFs) have been demonstrated to be desired candidates for sensing definite species owing to their tunable composition, framework structure and functionality. In this work, the NH₂-MIL-101 series was utilized for sensing specific amino acids. The results show that cysteine (Cys) can significantly enhance the fluorescence emission of NH₂-MIL-101-Fe suspended in water, while NH₂-MIL-101-Al exhibits the ability to sense lysine (Lys), arginine (Arg) and histidine (His) in aqueous media via turn-on fluorescence emission. Titration experiments ensure that NH₂-MIL-101-Fe and NH₂-MIL-101-Al can selectively and quantitatively detect these amino acids. The sensing mechanism was examined and discussed. The results of this study show that the metal centers in MOFs are crucial for sensing specific amino acids.     

Construction of NH2-MIL-125(Ti) nanoplates modified Bi2WO6 microspheres with boosted visible-light photocatalytic activity

Photoactive metal–organic frameworks (MOFs) have proven to be a promising porous material in the field of catalysis. Controllable integration of these MOFs with inorganic semiconductor materials may endow new multifunctional hybrid materials with preferable photocatalytic properties. In this research, NH₂-MIL-125(Ti) nanoplates modified Bi₂WO₆ microspheres was prepared via a simple solvothermal method. The photocatalytic behaviors of the acquired catalysts was evaluated via the degradation of tetracycline hydrochloride (TC) under visible light. The experimental results showed that NH₂-MIL-125(Ti)/Bi₂WO₆ composites display higher photocatalytic activity than that of single Bi₂WO₆, and the ideal incorporation amount of NH₂-MIL-125(Ti) was around 5 wt%. The steady state fluorescence spectrum, transient photocurrents and electrochemical impedance spectroscopy verified that the introduction of NH₂-MIL-125(Ti) could accelerate the separation and transfer of photogenerated carriers and thus improve the photocatalytic activity of Bi₂WO₆. The photocatalytic mechanism was explored in detail. This work extends the knowledge of integrating MOFs with traditional photocatalysts to form new composite materials in the area of environmental purification.

     

Oriented Ultrathin π-complexation MOF Membrane for Ethylene/Ethane and Flue Gas Separations

Rational design and engineering of high-performance molecular sieve membranes towards C₂H₄/C₂H₆ and flue gas separations remain a grand challenge to date. In this study, through combining pore micro-environment engineering with meso-structure manipulation, highly c-oriented sub-100 nm-thick Cu@NH₂-MIL-125 membrane was successfully prepared. Coordinatively unsaturated Cu ions immobilized in the NH₂-MIL-125 framework enabled high-affinity π-complexation interactions with C₂H₄, resulting in an C₂H₄/C₂H₆ selectivity approaching 13.6, which was 9.4 times higher than that of pristine NH₂-MIL-125 membrane; moreover, benefiting from π-complexation interactions between CO₂ and Cu(I) sites, our membrane displayed superior CO₂/N₂ selectivity of 43.2 with CO₂ permeance of 696 GPU, which far surpassed the benchmark of other pure MOF membranes. The above multi-scale structure optimization strategy is anticipated to present opportunities for significantly enhancing the separation performance of diverse molecular sieve membranes.     

Vibrational behavior of matrix-isolated ions in Tutton compounds. V. Infrared spectroscopic study of NH4+ and SO42− ions included in zinc sulfates and selenates

Infrared spectra of K₂Zn(SeO₄)₂·6H₂O and (NH₄)₂Zn(SeO₄)₂·6H₂O containing SO₄^2? guest ions and those of K₂Zn(SO₄)₂·6H₂O and K₂Zn(SeO₄)₂·6H₂O containing NH₄⁺ guest ions are presented and discussed in the region of the stretching modes ν₃ and ν₁ of the sulfate ions and in the region of asymmetric bending modes ν₄ of the NH₄⁺ ions, respectively. The SO₄^2? ions matrix-isolated in the selenate matrices (approximately 2 mol%) exhibit three bands for ν₃ and one band for ν₁ in agreement with the low site symmetry C₁ of the selenate host ions. The NH₄⁺ guest ions included in the potassium sulfate matrix are characterized also with three site symmetry components of ν₄. However, the ammonium ions in (NH₄)₂Zn(SeO₄)₂·6H₂O as well as those included in K₂Zn(SeO₄)₂·6H₂O display four infrared bands corresponding to ν₄ probably due to some kind of disorder of the ammonium ions. The extent of energetic distortion of the isomorphously included sulfate ions as deduced from the values of Δν₃ (site-group splitting) and Δν_max (the difference between the highest and the lowest wavenumbered components of the stretching modes) are commented. The spectroscopic experiments reveal that the SO₄^2? guest ions are weaker distorted in the potassium selenate matrix than the same ions in the neat potassium sulfate due to the larger unit-cell volumes of the selenate compounds. However, the SO₄^2? guest ions are stronger distorted in the ammonium selenate matrix as compared to the same ions in the neat ammonium sulfate owing to the formation of hydrogen bonds between the SO₄^2? guest ions and the NH₄⁺ host ions. The analysis of the spectra shows that the band positions of the water librations in the host potassium compounds are affected by the included ammonium cations. The formation of the hydrogen bonds between the NH₄⁺ guest ions and the XO₄^2? host ions leads to a decrease in the proton acceptor capabilities of the anions (anti-cooperative or proton acceptor competitive effect) and as a result the hydrogen bonds formed by the water molecules weaken on going from the neat potassium compounds to the mixed crystals K_1.8(NH₄)_0.2Zn(SO₄)₂·6H₂O and K_1.8(NH₄)_0.2Zn(SeO₄)₂·6H₂O (the bands corresponding to water librations are broadened and shifted to lower frequencies).     

MIL-125(Ti)及其氨基功能化材料修饰石英晶体微天平的湿敏性能

采用简单的溶剂热法制备金属有机框架化合物MIL-125(Ti)和NH_2-MIL-125(Ti)材料,并通过X射线衍射仪、扫描电子显微镜、傅氏转换红外线光谱分析仪和比表面积测试仪对所得样品进行表征。将2种材料修饰构建为石英晶体微天平传感器,测试其在11%～97%RH相对湿度范围内的湿度感测性能。实验结果表明,基于MIL-125(Ti)和NH_2-MIL-125(Ti)构建的传感器对湿度具有灵敏度高、重复性好、响应/恢复快等特点。相对于没有氨基修饰的MIL-125(Ti),NH_2-MIL-125(Ti)材料修饰的传感器对湿度表现出更高的响应性能。在环境湿度约52%时,NH_2-MIL-125(Ti)传感器对11%RH湿度响应值比MIL-125(Ti)湿度传感器的大57 Hz,说明氨基功能化对MIL-125(Ti)的湿敏性能有显著的增强作用。此外,通过Materials Studio模拟计算获得了水分子与MIL-125(Ti)及NH_2-MIL-125(Ti)作用的吸附焓,也证明氨基功能化对MIL-125(Ti)的湿度敏感性能具有增强作用。     

Über einen Isokonzentrationsschnitt in bezug auf Schwefelsäure im Dreistoffsystem Ammoniumsulfat-Eisen(III)sulfat-Wasser bei 25 °C

Zusammenfassung Untersucht wird ein Isokonzentrationsschnitt in bezug auf Schwefelsäure im Dreistoffsystem (NH₄)₂SO₄–Fe₂(SO₄)₃–H₂O bei 25 °C. Es wird ein Kristallisationsbereich von anomalen Mischkristallen auf der Basis (NH₄)₂SO₄ bei einem Eisen(III)-sulfatgehalt von 1,5% des Ammoniumsulfatgehalts ermittelt. Außerdem wird ein Kristallisationsbereich von Mischkristallen auf der Basis NH₄Fe(SO₄)₂·12 H₂O, ein Kristallisationsbereich von reinem NH₄Fe(SO₄)₂·12 H₂O und ein Kristallisationsbereich von Fe₂(SO₄)₃·9 H₂O festgestellt. Die Anwesenheit von Schwefelsäure in der Lösung vermindert die Löslichkeit aller Phasen im obigen System.Untersucht wird teilweise das Dreistoffsystem NH₄Fe(SO₄)₂–H₂SO₄–H₂O bei 25 °C. Es wird ein Kristallisationsbereich von NH₄Fe(SO₄)₂·12 H₂O, welches als feste Phase bis etwa 12% Schwefelsäure in der Lösung existiert, ermittelt. Es wird bewiesen, daß die anomalen Mischkristalle auf der Basis (NH₄)₂SO₄ metastabile, mit der Zeit langsamen Veränderungen unterliegende Systeme sind.

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An isoconcentration section with respect to sulphuric acid of the ternary system ammonium sulphate-ferric sulphate-water at 25 °C

The system (NH₄)₂SO₄–Fe₂(SO₄)₃–H₂O was investigated at 25 °C with an excess of H₂SO₄. The crystallization ranges of the anomalous mixed crystals based on ammonium sulphate, the mixed crystals on the basis of the double-salt NH₄Fe(SO₄)₂· ·12 H₂O, the crystallization ranges of Iron(III)-ammonium sulphate and Fe₂(SO₄)₃·9 H₂O were determined. The presence of H₂SO₄ in the solution lowers the solubilities of the different phases occurring in the said system. The system NH₄Fe(SO₄)₂–H₂SO₄–H₂O was partially studied at 25 °C. The crystallization range of iron-ammonium alum existing as a solid phase at equilibrium at sulphuric acid concentrations up to ca. 12% in the solution is described. It was shown that the anomalous mixed-crystals based on ammonium sulphate undergoe slow changes with time.

     

Contribution à l'étude du système quaternaire K+—NH4+—CrO4−−—SO4−−—H2O: I. les isothermes de 25° des systèmes ternaires limites

The four ternary limiting isotherms of the system K⁺− NH₄⁺ CrO₄⁻⁻ SO₄⁻⁻ H₂O are given for 25° C. In the systems K₂SO₄ (NH₄)₂SO₄ H₂O and K₂SO₄ K₂CrO₄ H₂O only one solid phase has been encountered; both systems belong to the type I of the ROOZEBOOM classification. A miscibility gap is present in the systems (NH₄)₂CrO₄ K₂CrO₄ H₂O and (NH₄)₂CrO₄ (NH₄)₂SO₄ H₂O; they belong to ROOZEBOOM'S type V.     

Photocatalytic Activities of FeNbO4/NH2-MIL-125(Ti) Composites toward the Cycloaddition of CO2 to Propylene Oxide

Photocatalytic utilization of CO₂ in the production of value-added chemicals has presented a recent green alternative for CO₂ fixation. In this regard, three FeNbO₄/NH₂-MIL-125(Ti) composites of different mole ratios were synthesized, characterized using Powder X-ray diffraction (PXRD), UV–vis diffuse reflectance spectroscopy (UV-Vis DRS), Brunauer–Emmett–Teller (BET), Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray (EDX). PXRD patterns confirm the co-existence of the parent components in the prepared composites. Moreover, the surface area increased as the mole percent of NH₂-MIL-125(Ti) in the composites increased due to the large surface area of NH₂-MIL-125(Ti). Prepared composites were investigated for the photocatalytic insertion of CO₂ into propylene oxide. FeNbO_4(75%)/NH₂-MIL-125(Ti)_(25%) showed the highest percent yield of 52% compared to the other two composites. Results demonstrate the cooperative mechanism between FeNbO₄ and NH₂-MIL-125(Ti) and that the reaction proceeded photocatalytically.     

Solid-Phase “Self-Hydrolysis” of [Zn(NH3)4MoO4@2H2O] Involving Enclathrated Water—An Easy Route to a Layered Basic Ammonium Zinc Molybdate Coordination Polymer

An aerial humidity-induced solid-phase hydrolytic transformation of the [Zn(NH₃)₄]MoO₄@2H₂O (compound 1@2H₂O) with the formation of [(NH₄)_xH_(1−x)Zn(OH)(MoO₄)]_n (x = 0.92–0.94) coordination polymer (formally NH₄Zn(OH)MoO₄, compound 2) is described. Based on the isostructural relationship, the powder XRD indicates that the crystal lattice of compound 1@2H₂O contains a hydrogen-bonded network of tetraamminezinc (2+) and molybdate (2−) ions, and there are cavities (O₄N₄(μ-H₁₂) cube) occupied by the two water molecules, which stabilize the crystal structure. Several observations indicate that the water molecules have no fixed positions in the lattice voids; instead, the cavity provides a neighborhood similar to those in clathrates. The @ symbol in the notation is intended to emphasize that the H₂O in this compound is enclathrated rather than being water of crystallization. Yet, signs of temperature-dependent dynamic interactions with the wall of the cages can be detected, and 1@2H₂O easily releases its water content even on standing and yields compound 2. Surprisingly, hydrolysis products of 1 were observed even in the absence of aerial humidity, which suggests a unique solid-phase quasi-intramolecular hydrolysis. A mechanism involving successive substitution of the ammonia ligands by water molecules and ammonia release is proposed. An ESR study of the Cu-doped compound 2 (2#dotCu) showed that this complex consists of two different Cu²⁺(Zn²⁺) environments in the polymeric structure. Thermal decomposition of compounds 1 and 2 results in ZnMoO₄ with similar specific surface area and morphology. The ZnMoO₄ samples prepared from compounds 1 and 2 and compound 2 in itself are active photocatalysts in the degradation of Congo Red dye. IR, Raman, and UV studies on compounds 1@2H₂O and 2 are discussed in detail.     

Crosslinking behavior and enhanced mechanical properties of acrylonitrile‐butadiene rubber composites by incorporating aluminum ammonium sulfate particles

The crosslinked structure formed by the metal coordination bonding provides excellent and new properties for rubber materials. Herein, the crosslinking of acrylonitrile‐butadiene rubber (NBR) is induced by introducing aluminum ammonium sulfate (NH₄Al(SO₄)₂·12H₂O) particles. The crosslinking behavior, morphology, mechanical properties, and the Akron abrasion resistance of NBR/NH₄Al(SO₄)₂·12H₂O composites were fully explored. The results show that the three‐dimensional crosslinking structure is held together by metal–ligand coordination bonds between the nitrile group and AI(III). The coordination crosslink density exhibits a considerable increase with the addition of NH₄Al(SO₄)₂·12H₂O. Thus, the mechanical properties and abrasion resistance of the obtained composites are better than that of NBR/sulfur system. Interestingly, the elongation at break for NBR/NH₄Al(SO₄)₂·12H₂O composites is over 2000% due to the nature of coordination bonds. The abrasion volume loss decreases to 0.4 cm³ for NBR/NH₄Al(SO₄)₂·12H₂O composites with 20 phr NH₄Al(SO₄)₂·12H₂O particles as compared to 0.75 cm³ for NBR/sulfur system. The obtained NBR composites with facile preparation and excellent mechanical properties make the composites based on metal coordination bonding attractive for practical use. © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2019 , 57, 879–886     

IR spectra and thermal decomposition/dehydration of double complex salts of lanthanum(III) sulphate complex anions with several cobalt(III) ammine complex cations

Double complex salts of lanthanum(III) sulphate complex anions with several cobalt(III) ammine complex cations, [Co(NH₃)₆][La(SO₄)₃]·H₂O (1), (NH₄)₃[Co(NH₃)₅ H₂O]-[La(SO₄)₃]₂·2H₂O (2), and (NH₄)₃[Co(NH₃)₄(H₂O)₂][La(SO₄)₃]₂·2H₂O (3), were prepared by the addition of hexaamminecobalt(III), pentaammineaquacobalt(III), and cis- tetra-amminediaquacobalt(III) complexes to the solution containing lanthanum(III) ion and excess ammonium sulphate. The IR spectra of sulphate groups of these double complex salts were much more complicated than those of the almost free sulphate groups such as (NH₄)₂SO₄ and [Co(NH₃)₆]₂(SO₄)₃·5H₂O. Furthermore, values of activation energy in the dehydration process of 1, 2 and 3 were estimated using modified Doyle's and Wiedemann's method. They were 95.6 ± 4.3, 157.1 ± 15.5 and 163.2 ± 20.8 kJ mol^?1, respectively. Here, one molecule water is released per molecule of 1, 2 and 3.     

Author index

The thermal decomposition of N₂H₅Nd(SO₄)₂·H₂O has been studied by simultaneous TG and DSC and by isothermal weight change determination. The final product and the intermediate phases have been identified by chemical analysis, X-ray powder patterns and infrared spectroscopy. The solid phases in the decomposition sequence are: N₂H₅Nd(SO₄)₂· H₂O → N₂H₅Nd(SO₄)₂ → NH₄Nd(SO₄)₂ → Nd₂(SO₄)₃. The reactions overlap under dynamicconditions, isothermally, however, NH₄Nd(SO₄)₂ can be obtained by 200°C.     

Supramolecular compounds of indium sulfates with nitrogen-containing cations

Compounds with a general formula [Cat][In(H₂O) _n (SO₄)₂] _x · mH₂O (where Cat = C(NH₂)₃, H(2,2′-Bipy), H₂(4,4′-Bipy), H₂[Py(CH₂)₃Py], and H₃N(CH₂)₆NH₃) were synthesized and identified from the elemental analysis, IR, and thermogravimetric analysis data. X-ray diffraction analysis of crystalline [C(NH₂)₃][In(H₂O)₂(SO₄)₂] complex showed that the polymer chains of In aquasulfate form ensembles with guanidinium ions. The structure of [H₂(4,4′-Bipy)][In₂(H₂O)₆(SO₄)₄] · 2H₂O consists of the dimeric anions of indium sulfate. The coordination sphere of In includes three O atoms of three SO₄ groups and three O atoms of water molecules. The dimers are united into framework by diprotonated Bipy cations.     

A theoretical investigation on the structures of (NH3)·(H2SO4)·(H2O)0-14 clusters

Ternary clusters (NH₃)·(H₂SO₄)·(H₂O)_n have been widely studied. However, the structures and binding energies of relatively larger cluster (n > 6) remain unclear, which hinders the study of other interesting properties. Ternary clusters of (NH₃)·(H₂SO₄)·(H₂O)_n, n = 0-14, were investigated using MD simulations and quantum chemical calculations. For n = 1, a proton was transferred from H₂SO₄ to NH₃. For n = 10, both protons of H₂SO₄ were transferred to NH₃ and H₂O, respectively. The NH₄⁺ and HSO₄⁻ formed a contact ion-pair [NH₄⁺-HSO₄⁻] for n = 1-6 and a solvent separated ion-pair [NH₄⁺-H₂O-HSO₄⁻] for n = 7-9. Therefore, we observed two obvious transitions from neutral to single protonation (from H₂SO₄ to NH₃) to double protonation (from H₂SO₄ to NH₃ and H₂O) with increasing n. In general, the structures with single protonation and solvated ion-pair were higher in entropy than those with double protonation and contact ion-pair of single protonation and were thus preferred at higher temperature. As a result, the inversion between single and double protonated clusters was postponed until n = 12 according to the average binding Gibbs free energy at the normal condition. These results can serve as a good start point for studies of the other properties of these clusters and as a model for the solvation of the [H₂SO₄-NH₃] complex in bulk water.     

Phenol as a guest molecule in clathrate compounds

Phenol, having favourable physical and chemical properties, can be enclosed as the guest component in the clathrates of tetracyano complexes. Six compounds of Hofmann and similar type clathrates M(NH₃)₂M' (CN)₄.nG and M(en)_m M'(CN)₄.nG were prepared and identified: Ni(NH₃)₂Pt.2C₆H₅OH; Ni(en)₂Pt(CN)₄.O.14C₆H₅OH; Ni(NH₃)₂Pt(CN)₄.C₆H₅OH.H₂O; Zn(NH₃)₂Ni(CN)₄.O.1C₆H₅OH.H₂O; Cu(NH₃)₂Ni(CN)₄. 2C₆H₅OH and Fe(NH₃)₂Ni(CN)₄.2C₆H₅OH. The phenol containing clathrates are more stable than clathrates containing other guest molecules. In the case of Ni(en)₂ Pt(CN)₄.O.14C₆H₅OH thermal loss of the guest molecule leaves the host lattice intact, but further heating results in the rupture of the host lattice. The compounds were capable in the solid state of sorbing other organic molecules once they had been heated to the temperature required for almost complete loss of guest molecule i.e. n→o.     

The study of the existence of unknown and unstable compounds through mixed crystal formation using radioactive tracers

A heterogeneous distribution study with internally formed lead chromate as host and¹¹⁰Ag as guest indicates the existence of a new variety of lead chromate, which forms mixed crystals with silver chromate, and differs in morphology from the aged variety. It is inferred that the formation of mixed crystals is probably due to breeding of a morphologically analogous and unstable species by the guest component. By means of study of the homogeneous distribution coefficient, D, of the system consisting of KFe(SO₄)₂·12H₂O as host and¹¹⁰Ag as guest, the existence of an unknown alum, AgFe(SO₄)₂·12H₂O, in trace amounts has been demonstrated. A distribution study of the system shows that KFe(SO₄)₂·12H₂O forms mixed crystals with¹¹⁰Ag up to 10°C, after which the uptake follows an adsorption pattern. The transition temperature of the guest alum, indicated by a sharp change in the D values, is found to be 10°C. Application of radioactive tracers in the study of new and unstable compounds have been stressed.     

Thermodynamics of ionic solid solutions: III. An addendum

In two earlier papers (C.A. 117:259320(1;121:19411y) the activity coefficients of the salts in binary solid solutions at 25‡C for 38 salt pairs, in which the members of each pair differ with respect to only one kind of ion, were determined. While the activity data are correct, the conclusions regarding deviations from ideality for eight of these pairs, namely those in which there are two moles of replaceable ion per mole of salt, require modification in order to be consistent with ideal entropies of mixing. By changing the formulation of the component salts to one-half of what is usual, the inconsistencies disappear. This half-mole approach, applied to the salt pairs CU_1/2(NH₄/K)SO₄-3H₂O, Mg_1/2NH₄(SO₄/ CrO₄)-3H₂O, Mg_1/2NH₄(SeO₄/SO₄)-3H₄O, Mg_1/2NH₄(SeO₄/CrO₄)-3H₄O, Mg_1/2 (K/NH₄)SeO₄-3H₂O, (NH₄/K)(SO₄)_1/2, and Ba_1/2(ClO₃/BrO₃)-1/2 H₂O shows that these solid solutions exhibit positive, not negative, deviations from ideality at 25‡C. Only the system Pb_1/2(C1/Br) still deviates negatively.     

Accelerated FeIII/FeII redox cycle of Fenton reaction system using Pd/NH2-MIL-101(Cr) and hydrogen

In this paper, a novel improvement in the catalytic Fenton reaction system named MHACF-NH₂-MIL-101(Cr) was constructed based on H₂ and Pd/NH₂-MIL-101(Cr). The improved system would result in an accelerated reduction in Fe^III, and provide a continuous and fast degradation efficiency of the 10 mg L^-1 4-chlorophenol which was the model contaminant by using only trace level Fe^II. The activity of Pd/NH₂-MIL-101(Cr) decreased from 100% to about 35% gradually during the six consecutive reaction cycles of 18 h. That could be attributed to the irreversible structural damage of NH₂-MIL-101(Cr).     

Amine-Functionalized Metal–Organic Framework as a New Sorbent for Vortex-Assisted Dispersive Micro-Solid Phase Extraction of Phenol Residues in Water Samples Prior to HPLC Analysis: Experimental and Computational Studies

Metal–organic frameworks (MOFs) are a new class of hybrid inorganic–organic microporous crystalline materials, which possess unique properties such as high surface area, tunable pore size, and good thermal stability. These unique characteristics make MOFs interesting targets for sample pretreatment. In this work, MIL-53 material based on aluminum and containing amine functional groups (NH₂-MIL-53(Al)) was synthesized and applied as an efficient sorbent for development of vortex-assisted dispersive micro-solid phase extraction for eight United States Environmental Protection Agency’s priority phenols from aqueous samples prior to analysis by high-performance liquid chromatography with photodiode-array detection. A simple extraction process was designed. The parameters affecting the extraction efficiency, such as amount of sorbent, extraction time, type of desorption solvent and its volume were investigated. The good linearity in the concentration range of 0.0015–10.0000 μg mL^?1 with the coefficients of determination of greater than 0.9929, low limits of detection (0.0004–0.0133 μg mL^?1) and relative standard deviations of lower than 10% were obtained. The proposed method has been successfully applied to the determination of phenol compounds in different water sample matrices including treated water, waste water, river water, sea water, lake water, drinking water and tap water. In addition, computational simulation was performed to predict the adsorption ability of NH₂-MIL-53(Al) towards the studied phenolic compounds. The computational results were in agreement with the experimental studies and it has been proved that NH₂-MIL-53(Al) is promising for enrichment of phenolic pollutants.     

Crystal structure of fluorosulfate complex compounds of indium(III) M<Subscript>2</Subscript>[InF<Subscript>3</Subscript>(SO<Subscript>4</Subscript>)H<Subscript>2</Subscript>O] (M = K,NH<Subscript>4</Subscript>)

The crystal structures of isostructural mixed-ligand fluorosulfate complex compounds of indium(III) M₂[InF₃(SO₄)H₂O] (M = K, NH₄), formed of K⁺ cations, NH₄ ⁺ respectively, and complex [InF₃(SO₄)H₂O]^2– anions are determined. In the complex anion, the indium atom surrounded by three F atoms, the oxygen atom of the coordinated H₂O molecule, and two oxygen atoms of the bridging sulfate group forms a slightly distorted octahedron (CN 6). Via alternating bridging SO₄ groups, the polyhedra of In(III) atoms are arranged in polymer chains. The O–H???F hydrogen bonds organize the chains in a three-dimensional network. The K⁺ and NH₄ ⁺ cations are located in the structure framework and additionally strengthen it.