High-throughput and time-resolved energy-dispersive X-ray diffraction (EDXRD) study of the formation of CAU-1-(OH)2: microwave and conventional heating

Aluminium dihydroxyterephthalate [Al₈(OH)₄(OCH₃)₈(BDC(OH)₂)₆] ? x H₂O (denoted CAU‐1‐(OH)₂) was synthesized under solvothermal conditions and characterized by X‐ray powder diffraction, IR spectroscopy, sorption measurements, as well as thermogravimetric and elemental analysis. CAU‐1‐(OH)₂ is isoreticular to CAU‐1 and its pores are lined with OH groups. It is stable under ambient conditions and in water, and it exhibits permanent porosity and two types of cavities with effective diameters of approximately 1 and 0.45 nm. The crystallization of CAU‐1‐(OH)₂ was studied by in situ energy‐dispersive X‐ray diffraction (EDXRD) experiments in the 120–145 °C temperature range. Two heating methods—conventional and microwave—were investigated. The latter leads to shorter induction periods as well as shorter reaction times. Whereas CAU‐1‐(OH)₂ is formed at all investigated temperatures using conventional heating, it is only observed below 130 °C using microwave heating. The calculation of the activation energy of the crystallization of CAU‐1‐(OH)₂ exhibits similar values for microwave and conventional synthesis.     

A Computational and Experimental Approach Linking Disorder,High‐Pressure Behavior,and Mechanical Properties in UiO Frameworks

Whilst many metal–organic frameworks possess the chemical stability needed to be used as functional materials, they often lack the physical strength required for industrial applications. Herein, we have investigated the mechanical properties of two UiO‐topology Zr‐MOFs, the planar UiO‐67 ([Zr₆O₄(OH)₄(bpdc)₆], bpdc: 4,4′‐biphenyl dicarboxylate) and UiO‐abdc ([Zr₆O₄(OH)₄(abdc)₆], abdc: 4,4′‐azobenzene dicarboxylate) by single‐crystal nanoindentation, high‐pressure X‐ray diffraction, density functional theory calculations, and first‐principles molecular dynamics. On increasing pressure, both UiO‐67 and UiO‐abdc were found to be incompressible when filled with methanol molecules within a diamond anvil cell. Stabilization in both cases is attributed to dynamical linker disorder. The diazo‐linker of UiO‐abdc possesses local site disorder, which, in conjunction with its longer nature, also decreases the capacity of the framework to compress and stabilizes it against direct compression, compared to UiO‐67, characterized by a large elastic modulus. The use of non‐linear linkers in the synthesis of UiO‐MOFs therefore creates MOFs that have more rigid mechanical properties over a larger pressure range.     

The First 3‐Connected SrSi2‐Type 3D Chiral Framework Constructed from {Ni6PW9} Building Units

A novel 3‐connected SrSi₂‐type 3D chiral framework constructed from hexa‐Ni^II‐cluster‐substituted polyoxometalate (POM) units [Ni(enMe)₂]₃[WO₄]₃[Ni₆(enMe)₃(OH)₃PW₉O₃₄]₂?9H₂O ( 1 ) (enMe=1,2‐diaminopropane) has been made from a hydrothermal synthetic method. This POM represents the first 3D framework based on {Ni₆PW₉} units and {WO₄} connectors.     

Cobalt(II) Complexes with N‐Thioacylamidophosphates and 2,2′‐Bipyridyl and 1,10‐Phenathroline. Crystal Structures,Solution 1H NMR Spectral and Magnetic Properties

Structure and magnetic properties of N‐diisopropoxyphosphorylthiobenzamide PhC(S)‐N(H)‐P(O)(OiPr)₂ ( HL^I ) and N‐diisopropoxyphosphoryl‐N′‐phenylthiocarbamide PhN(H)‐C(S)‐N(H)‐P(O)(OiPr)₂ ( HL^II ) complexes with the Co^II cation of formulas [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂] ( 1 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂] ( 2 ), [Co{PhC(S)‐N(H)‐P(O)(OiPr)₂}₂{PhC(S)‐N‐P(O)(OiPr)₂}₂] ( 1a ) and [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂}(2,2′‐bipy)] ( 3 ), [Co{PhC(S)‐N‐P(O)(OiPr)₂}₂(1,10‐phen)] ( 4 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂(2,2′‐bipy)] ( 5 ), [Co{PhN(H)‐C(S)‐N‐P(O)(OiPr)₂}₂(1,10‐phen)] ( 6 ) were investigated. Paramagnetic shifts in the ¹H NMR spectrum were observed for high‐spin Co^II complexes with HL^I,II , incorporating the S‐C‐N‐P‐O chelate moiety and two aromatic chelate ligands. Investigation of the thermal dependence of the magnetic susceptibility has shown that the extended materials 1‐2 and 6 show ferromagnetic exchange between distorted tetrahedral ( 1 , 2 ) or octahedral ( 1a , 6 ) metal atoms whereas 3 and 5 show antiferromagnetic properties. Compound 4 behaves as a spin‐canted ferromagnet, an antiferromagnetic ordering taking place below a critical temperature, T_c = 115 K. Complexes 1 and 1a were investigated by single crystal X‐ray diffraction. The cobalt(II) atom in complex 1 resides a distorted tetrahedral O₂S₂ environment formed by the C=S sulfur atoms and the P=O oxygen atoms of two deprotonated ligands. Complex 1a has a tetragonal‐bipyramidal structure, Co(O^ax)₂(O^eq)₂(S^eq)₂, and two neutral ligand molecules are coordinated in the axial positions through the oxygen atoms of the P=O groups. The base of the bipyramid is formed by two anionic ligands in the typical 1,5‐O,S coordination mode. The ligands are in a trans configuration.     

Isomorphous rare‐earth tris[bis(2,6‐diisopropylphenyl) phosphate] complexes and their catalytic properties in 1,3‐diene polymerization and in the inhibited oxidation of polydimethylsiloxane

Crystals of mononuclear tris[bis(2,6‐diisopropylphenyl) phosphato‐κO]pentakis(methanol‐κO)lanthanide methanol monosolvates of lanthanum, [La(C₂₄H₃₄O₄P)₃(CH₃OH)₅]·CH₃OH, ( 1 ), cerium, [Ce(C₂₄H₃₄O₄P)₃(CH₃OH)₅]·CH₃OH, ( 2 ), and neodymium, [Nd(C₂₄H₃₄O₄P)₃(CH₃OH)₅]·CH₃OH, ( 3 ), have been obtained by reactions between LnCl₃(H₂O)_n (n = 6 or 7) and lithium bis(2,6‐diisopropylphenyl) phosphate in a 1:3 molar ratio in methanol media. Compounds ( 1 )–( 3 ) crystallize in the monoclinic P2₁/c space group and have isomorphous crystal structures. All three bis(2,6‐diisopropylphenyl) phosphate ligands display a κO‐monodentate coordination mode. The coordination number of the metal atom is 8. Each [Ln{O₂P(O‐2,6‐ⁱPr₂C₆H₃)₂}₃(CH₃OH)₅] molecular unit exhibits four intramolecular O—H…O hydrogen bonds, forming six‐membered rings. The unit forms two intermolecular O—H…O hydrogen bonds with one noncoordinating methanol molecule. All six hydroxy H atoms are involved in hydrogen bonding within the [Ln{O₂P(O‐2,6‐ⁱPr₂C₆H₃)₂}₃(CH₃OH)₅]·CH₃OH unit. This, along with the high steric hindrance induced by the three bulky diaryl phosphate ligands, prevents the formation of a hydrogen‐bond network. Complexes ( 1 )–( 3 ) exhibit disorder of two of the isopropyl groups of the phosphate ligands. The cerium compound ( 2 ) demonstrates an essential catalytic inhibition in the thermal decomposition of polydimethylsiloxane in air at 573 K. Catalytic systems based on the neodymium complex tris[bis(2,6‐diisopropylphenyl) phosphato‐κO]neodymium, ( 3′ ), which was obtained as a dry powder of ( 3 ) upon removal of methanol, display a high catalytic activity in isoprene and butadiene polymerization.     

Organic‐Inorganic Hybrid Supramolecular Assemblies Based on Isomers [HxAs2Mo6O26](6–x)– Clusters

The arsenomolybdates [H₂As₂Mo₆O₂₆(H₂O)] · (H₂biyb)₂ · 2H₂O ( 1 ) and [H₃As₂Mo₆O₂₆] · (H₃pt)₂ ( 2 ) [biyb = 1,4‐bis(imidazol‐1‐ylmethyl)benzene, pt = 4′‐(3′′‐pyridyl)‐2,3′:6′3′′‐terpyridine] were synthesized via hydrothermal method. The structures of the compounds were characterized by single‐crystal X‐ray diffraction analyses, elemental analyses, IR spectroscopy, and TG analysis. Compounds 1 and 2 exhibit two isomeric forms of [H_xAs₂Mo₆O₂₆]^(6–x)–. The structure of 1 is constructed from the B‐type [H₂As₂Mo₆O₂₆(H₂O)]^4– polyanions and free biyb ligands via weak interactions to form 3D supramolecular framework with a {3 · 4 · 5³ · 6}{3 · 4³ · 5²}{3 · 5 · 6}²{3 · 5²}² topology structure. In compound 2 , the A‐type [H₃As₂Mo₆O₂₆]^3– clusters are surrounded by pt ligands through hydrogen bond interactions forming 3D supramolecular framework with a {4³ · 6³}²{4⁶ · 6⁶ · 8³} topology structure. The electrochemical behaviors, electrocatalytic and photocatalytic activities of 1 and 2 are detected.     

New Perspectives for Old Clusters: Anderson–Evans Anions as Building Blocks of Large Polyoxometalate Frameworks in a Series of Heterometallic 3 d–4 f Species

A series of nine [Sb₇W₃₆O₁₃₃Ln₃M₂(OAc)(H₂O)₈]^17? heterometallic anions ( Ln₃M₂ ; Ln=La–Gd, M=Co; Ln=Ce, M=Ni and Zn) have been obtained by reacting 3 d metal disubstituted Krebs‐type tungstoantimonates(III) with early lanthanides. Their unique tetrameric structure contains a novel {MW₉O₃₃} capping unit formed by a planar {MW₆O₂₄} fragment to which three {WO₂} groups are condensed to form a tungstate skeleton identical to that of a hypothetical trilacunary derivative of the ?‐Keggin cluster. It is shown, for the first time, that classical Anderson–Evans {MW₆O₂₄} anions can act as building blocks to construct purely inorganic large frameworks. Unprecedented reactivity in the outer ring of these disk‐shaped species is also revealed. The Ln₃M₂ anions possess chirality owing to a {Sb₄O₄} cluster being encapsulated in left‐ or right‐handed orientations. Their ability to self‐associate in blackberry‐type vesicles in solution has been assessed for the Ce₃Co₂ derivative.     

Different Metal Aggregation in Copper Acetate Chain Coordination Polymers with Dipyridyl Tethers Bearing Hydrogen Bonding Capable Functional Groups

Hydrothermal synthesis has afforded a pair of divalent copper acetate coordination polymers containing either 4, 4′‐dipyridylamine (dpa) or 4‐pyridylisonicotinamide (4‐pina), both of which hydrogen‐bonding capable central functional groups. X‐ray crystallography revealed that both exhibit a 1D chain dimensionality. Use of the kinked tethering ligand dpa produced [Cu(OAc)₂(dpa)]_n ( 1 ), which possesses a simple chain based on dpa linkage of isolated copper ions. On the other hand, employing the straighter amide ligand 4‐pina generated {[Cu(OAc)₂(4‐pina)] · 0.5H₂O}_n ( 2 ), which exhibits {Cu₂O₂} rhomboid dimers formed through bridging acetate ligands. Weak antiferromagnetic coupling [g = 1.984(3), J = –3.2(3) cm^–1] was observed within the axial‐equatorial bridged {Cu₂O₂} dimers in 2 , with possible ferrimagnetism due to spin canting below 11 K.     

Crystal Structure of a New Triply‐Bridged Cobalt(III) Dimer with 2, 2′‐Dipyridylamine (dipyam), [Co2(μ‐OH)2(μ‐OAc)(OAc)2(dipyam)2]AcO·EtOH

The structure of [Co₂(μ‐OH)₂(μ‐OAc)(OAc)₂(dipyam)₂]AcO · EtOH ( 1 ) has been determined by single‐crystal X‐ray analysis. The cationic complex may be described as a “di(μ‐hydroxo)(μ‐acetato)dicobalt(III)” core with chelating 2, 2′‐dipyridylamine and monodentate acetate ligands. The coordination polyhedron around each cobalt atom is a distorted octahedral. The dimers are linked in the crystal by N‐H···O_{ionic AcO} and C‐H···O_{monodentate AcO} hydrogen bonds. Spectroscopic data are also presented.     

The heterometallic cadmium–silver complex cis‐bis[dicyanidoargentato(I)‐κN]bis(5,5′‐dimethyl‐2,2′‐bipyridyl‐κ2N,N′)cadmium(II) monohydrate

In the title complex, [Ag₂Cd(CN)₄(C₁₂H₁₂N₂)₂]·H₂O or cis‐[Cd{Ag(CN)₂}₂(5,5′‐dmbpy)₂]·H₂O, where 5,5′‐dmbpy is 5,5′‐dimethyl‐2,2′‐bipyridyl, the asymmetric unit consists of a discrete neutral [Cd{Ag(CN)₂}₂(5,5′‐dmbpy)₂] unit and a solvent water molecule. The Cd^II cation is coordinated by two bidentate chelate 5,5′‐dmbpy ligands and two monodentate [Ag^I(CN)₂]⁻ anions, which are in a cis arrangement around the Cd^II cation, leading to an octahedral CdN₆ geometry. The overall structure is stabilized by a combination of intermolecular hydrogen bonding, and Ag^I...Ag^I and π–π interactions, forming a three‐dimensional supramolecular network.     

A 3D Hybrid Praseodymium–Antimony–Oxochloride Compound: Single‐Crystal‐to‐Single‐Crystal Transformation and Photocatalytic Properties

A 3D organic–inorganic hybrid compound, (2‐MepyH)₃ [{Fe(1,10‐phen)₃}₃][{Pr₄Sb₁₂O₁₈(OH) Cl_11.5}(TDC)_4.5({Pr₄Sb₁₂O₁₈(OH)Cl_9.5} Cl)] ? 3 (2‐Mepy) ? 28 H₂O ( 1 ; 2‐Mepy=2‐methylpyridine, 1,10‐phen=1,10‐phenanthroline, H₂TDC=thiophene‐2,5‐dicarboxylic acid), was hydrothermally synthesized and structurally characterized. Unusually, two kinds of high‐nuclearity clusters, namely [(Pr₄Sb₁₂O₁₈ (OH)Cl₁₁)(COO)₅]^5? and [(Pr₄Sb₁₂O₁₈ (OH)Cl₉)Cl(COO)₅]^4?, coexist in the structure of compound 1 ; two of the latter clusters are doubly bridged by two μ₂‐Cl^? moieties to form a new centrosymmetric dimeric cluster. An unprecedented spontaneous and reversible single‐crystal‐to‐single‐crystal transformation was observed, which simultaneously involved a notable organic‐ligand movement between the metal ions and an alteration of the bridging ion in the dimeric cluster, induced by guest‐release/re‐adsorption, thereby giving rise to the interconversion between compound 1 and the compound (2‐MepyH)₃[{Fe(1,10‐phen)₃}₃][{Pr₄Sb₁₂O₁₈(OH)Cl_11.5}(TDC)₄({Pr₄Sb₁₂O₁₈Cl_10.5(TDC)_0.5(H₂O)_1.5}O_0.5)] ? 25 H₂O ( 1′ ). The mechanism of this transformation has also been discussed in great detail. Photocatalytic H₂‐evolution activity was observed for compound 1′ under UV light with Pt as a co‐catalyst and MeOH as a sacrificial electron donor.     

Acetate-Functionalized Zirconium-Substituted Tungstogermanate, [Zr4O2(OH)2(CH3COO)2(α-GeW10O37)2]12−

The two acetate-functionalized zirconium(IV)-substituted tungstogermanates, Na₈K₄[Zr₄O₂(OH)₂(CH₃COO)₂(α-GeW₁₀O₃₇)₂] · 33H₂O and Na₈Cs₄[Zr₄O₂(OH)₂(CH₃COO)₂(α-GeW₁₀O₃₇)₂] · 32H₂O, were synthesized by the reaction of ZrOCl₂ with [A-α-GeW₉O₃₄]¹⁰⁻ in pH = 4.8 buffer and their structures were determined by single-crystal X-ray analysis. Both of them contain a centrosymmetric polyanion [Zr₄O₂(OH)₂(CH₃COO)₂(α-GeW₁₀O₃₇)₂]¹²⁻ consisting of two {α-GeW₁₀O₃₇} units sandwiching an inorganic–organic hybrid {Zr₄O₂(OH)₂(CH₃COO)₂} cluster. The polyanion contains a mixing of seven- and eight-coordinate Zr centres. The two compounds were also characterized by elemental analysis, IR spectroscopy, UV–vis and TG–DSC analysis.     

Cooperative Cluster Metalation and Ligand Migration in Zirconium Metal–Organic Frameworks

Cooperative cluster metalation and ligand migration were performed on a Zr‐MOF, leading to the isolation of unique bimetallic MOFs based on decanuclear Zr₆M₄ (M=Ni, Co) clusters. The M²⁺ reacts with the μ₃‐OH and terminal H₂O ligands on an 8‐connected [Zr₆O₄(OH)₈(H₂O)₄] cluster to form a bimetallic [Zr₆M₄O₈(OH)₈(H₂O)₈] cluster. Along with the metalation of Zr₆ cluster, ligand migration is observed in which a Zr–carboxylate bond dissociates to form a M–carboxylate bond. Single‐crystal to single‐crystal transformation is realized so that snapshots for cooperative cluster metalation and ligand migration processes are captured by successive single‐crystal X‐ray structures. In³⁺ was metalated into the same Zr‐MOF which showed excellent catalytic activity in the acetaldehyde cyclotrimerization reaction. This work not only provides a powerful tool to functionalize Zr‐MOFs with other metals, but also structurally elucidates the formation mechanism of the resulting heterometallic MOFs.     

X‐Ray Crystal Structures of Hexa‐oxotellurate Complexes of Ruthenium(VI) and Silver(III): Na6[RuO2{TeO4(OH)2}2]·16H2O and Na5[Ag{TeO4(OH)2}2]·16H2O

X‐ray crystal structures are reported for Na₆[RuO₂{TeO₄(OH)₂}₂]·16H₂O and Na₅[Ag{TeO₄(OH)₂}₂]·16H₂O which contain respectively Ru^VI and Ag^III coordinated to chelating bidentate tellurate ([TeO₄(OH)₂]⁴⁻) groups. Na₆[RuO₂{TeO₄(OH)₂}₂]·16H₂O: Space group P1¯, Z = 2, lattice dimensions at 120 K; a = 6.9865(1), b = 8.7196(2), c = 11.7395(2)Å, α = 74.008(1), β = 79.954(1), γ = 88.514(1)°; R1 = 0.025. Na₅[Ag{TeO₄(OH)₂}₂]·16H₂O: Space group P1¯, Z = 2, lattice dimensions at 120 K; a = 5.888(1), b = 8.932(1), c = 12.561(2)Å, α = 98.219(6), β = 97.964(9), γ = 93.238(14)°; R1 = 0.047.     

一个新颖镍配位阳离子修饰的还原型钼磷酸盐：Ni[Mo6O12(OH)3(PO4)(HPO4)3]2][Ni(H2O)2][Ni(H2O)(bipy)2]4·5H2O

水热合成并通过红外、热重、单晶X-射线衍射表征了一个新颖镍配位阳离子修饰的还原型钼磷酸盐,Ni[Mo₆O₁₂(OH)₃(PO₄)(HPO₄)₃]₂][Ni(H₂O)₂][Ni(H₂O)(bipy)₂]₄·5H₂O。单晶X-射线衍射研究表明,两个{Mo₆P₄}簇单元通过一个镍离子连接形成一个Ni[Mo₆P₄]₂二聚结构单元,其进一步和其他的镍配位阳离子连接成钼磷酸盐一维链状结构。在H₂O₂存在下的液－固体系中,使用该化合物催化氧化苯甲醛的探针反应结果表明,该化合物具有较高的催化氧化活性。     

Untersuchung von Hydrolysereaktionen zum Aufbau von Eisen(III)‐Oxo‐Aggregaten

Investigation of the Hydrolytic Build‐up of Iron(III)‐Oxo‐Aggregates The synthesis and structures of five new iron/hpdta complexes [{Fe^III₄(μ‐O)(μ‐OH)(hpdta)₂(H₂O)₄}₂Fe^II(H₂O)₄]·21H₂O ( 2 ), (pipH₂)₂[Fe₂(hpdta)₂]·8H₂O ( 4 ), (NH₄)₄[Fe₆(μ‐O)(μ‐OH)₅(hpdta)₃]·20.5H₂O ( 5 ), (pipH₂)_1.5[Fe₄(μ‐O)(μ‐OH)₃(hpdta)₂]·6H₂O ( 7 ), [{Fe₆(μ₃‐O)₂(μ‐OH)₂(hpdta)₂(H₄hpdta)₂}₂]·py·50H₂O ( 9 ) are described and the formation of these is discussed in the context of other previously published hpdta‐complexes (H₅hpdta = 2‐Hydroxypropane‐1, 3‐diamine‐N, N, N′, N′‐tetraacetic acid). Terminal water ligands are important for the successive build‐up of higher nuclearity oxy/hydroxy bridged aggregates as well as for the activation of substrates such as DMA and CO₂. The formation of the compounds under hydrolytic conditions formally results from condensation reactions. The magnetic behaviour can be quantified analogously up to the hexanuclear aggregate 5 . The iron(III) atoms in 1 ‐ 7 are antiferromagnetically coupled giving rise to S = 0 spin ground states. In the dodecanuclear iron(III) aggregate 9 we observe the encapsulation of inorganic ionic fragments by dimeric{M₂hpdta}‐units as we recently reported for Al^III/hpdta‐system.     

MOF‐on‐MOF: Oriented Growth of Multiple Layered Thin Films of Metal–Organic Frameworks

The precise alignment of multiple layers of metal–organic framework (MOF) thin films, or MOF‐on‐MOF films, over macroscopic length scales is presented. The MOF‐on‐MOF films are fabricated by epitaxially matching the interface. The first MOF layer (Cu₂(BPDC)₂, BPDC=biphenyl‐4,4′‐dicarboxylate) is grown on an oriented Cu(OH)₂ film by a “one‐pot” approach. Aligned second (Cu₂(BDC)₂, BDC=benzene 1,4‐dicarboxylate, or Cu₂(BPYDC)₂, BPYDC=2,2′‐bipyridine‐5,5′‐dicarboxylate) MOF layers can be deposited using liquid‐phase epitaxy. The co‐orientation of the MOF films is confirmed by X‐ray diffraction. Importantly, our strategy allows for the synthesis of aligned MOF films, for example, Cu₂(BPYDC)₂, that cannot be grown on a Cu(OH)₂ surface. We show that aligned MOF films furnished with Ag nanoparticles show a unique anisotropic plasmon resonance. Our MOF‐on‐MOF approach expands the chemistry of heteroepitaxially oriented MOF films and provides a new toolbox for multifunctional porous coatings.     

Three Series of Sulfo‐Functionalized Mixed‐Linker CAU‐10 Analogues: Sorption Properties,Proton Conductivity,and Catalytic Activity

Ten mixed‐linker metal–organic frameworks [Al(OH)(m‐BDC‐X)_1?y(m‐BDC‐SO₃H)_y] (H₂BDC=1,3‐benzenedicarboxylic acid; X=H, NO₂, OH) exhibiting the CAU‐10‐type structure were synthesized. The compounds can be grouped into three series according to the combination of ligands employed. The three series of compounds were obtained by employing different ratios of m‐H₂BDC‐X and m‐H₂BDC‐SO₃Li. The resulting compounds, which are denoted CAU‐10‐H/Sx, ‐N/Sx and ‐O/Sx, show exceptionally high thermal stability for sulfonated materials of up to 350 °C. Detailed characterization with special focus on polarity and acidity was performed, and the impact of the additional SO₃H groups is clearly demonstrated by changes in the sorption affinities/capacities towards several gases and water vapor. In addition, selected samples were evaluated for proton conductivity and as catalysts for the gas‐phase dehydration of ethanol to ethylene. While only very low proton conductivities were observed, a pronounced increase in catalytic activity was achieved. Although reactions were performed at temperatures of 250 and 300 °C for more than 40 h, no desulfonation and no loss of crystallinity were observed, and stable ethanol conversion resulted. This demonstrates the high stability of this material.     

The First Examples of Selenidogermanate Salts with Lanthanide Complex Counter Cations: Solvothermal Syntheses and Characterizations of [{Ln(en)3}2(μ‐OH)2]Ge2Se6 (Ln = Eu,Ho) and [{Ho(dien)2}2(μ‐OH)2]Ge2Se6

The lanthanide selenidogermanates [{Eu(en)₃}₂(μ‐OH)₂]Ge₂Se₆ ( 1 ), [{Ho(en)₃}₂(μ‐OH)₂]Ge₂Se₆ ( 2 ), and [{Ho(dien)₂}₂(μ‐OH)₂]Ge₂Se₆ ( 3 ) (en = ethylenediamine, dien = diethylenetriamine) were solvothermally prepared by the reactions of Eu₂O₃ (or Ho₂O₃), germanium, and selenium in en and dien solvents respectively. Compounds 1 – 3 are composed of selenidogermanate [Ge₂Se₆]^4– anion and dinuclear lanthanide complex cation [{Ln(en)₃}₂(μ‐OH)₂]⁴⁺ (Ln = Eu, Ho) or [{Ho(dien)₂}₂(μ‐OH)₂]⁴⁺. The [Ge₂Se₆]^4– anion is composed of two GeSe₄ tetrahedra sharing a common edge. The dinuclear lanthanide complex cations are built up from two [Ln(en)₃]³⁺ or [Ho(dien)₂]³⁺ ions joined by two μ‐OH bridges. All lanthanide(III) ions are in eight‐coordinate environments forming distorted bicapped trigonal prisms. In 1 – 3 , three‐dimensional supramolecular networks of the anions and cations are formed by N–H ··· Se and N–H ··· O hydrogen bonds. To the best of our knowledge, 1 – 3 are the first examples of selenidogermanate salts with lanthanide complex counter cations.     

A Computational and Experimental Approach Linking Disorder,High‐Pressure Behavior,and Mechanical Properties in UiO Frameworks

Whilst many metal–organic frameworks possess the chemical stability needed to be used as functional materials, they often lack the physical strength required for industrial applications. Herein, we have investigated the mechanical properties of two UiO‐topology Zr‐MOFs, the planar UiO‐67 ([Zr₆O₄(OH)₄(bpdc)₆], bpdc: 4,4′‐biphenyl dicarboxylate) and UiO‐abdc ([Zr₆O₄(OH)₄(abdc)₆], abdc: 4,4′‐azobenzene dicarboxylate) by single‐crystal nanoindentation, high‐pressure X‐ray diffraction, density functional theory calculations, and first‐principles molecular dynamics. On increasing pressure, both UiO‐67 and UiO‐abdc were found to be incompressible when filled with methanol molecules within a diamond anvil cell. Stabilization in both cases is attributed to dynamical linker disorder. The diazo‐linker of UiO‐abdc possesses local site disorder, which, in conjunction with its longer nature, also decreases the capacity of the framework to compress and stabilizes it against direct compression, compared to UiO‐67, characterized by a large elastic modulus. The use of non‐linear linkers in the synthesis of UiO‐MOFs therefore creates MOFs that have more rigid mechanical properties over a larger pressure range.