C3H6 adsorption on a family of NIIC-20-G (G = glycol) MOFs is carried out. The C3H6 adsorption capacities at 1 bar vary from 109.3 to 168 ml & sdot;g-1 (273 K) and from 74.2 to 113.3 ml & sdot;g-1 (298 K), depending on the nature of G. The following highest IAST adsorption selectivity values (S) are obtained at 298 K, 1:1 gas mixture, 1 bar: S (C3H6/CO2) = 7.4, S(C3H6/CH4) = 587.0, S(C3H6/C2H6) = 4.4, S(C3H6/C2H4) = 7.0, S(C3H8/C3H6) = 2.1. The isosteric heats of the C3H6 adsorption range from 32.4 to 38.0 kJ center dot mol-1, which are lower than that of C3H8, suggesting enthalpy-driven preferential adsorption of propane over propylene. Theoretical DFT and GCMC calculations support the experimental results and provide more detailed information on the nature of adsorption centers of propane and propylene molecules. Multiple breakthrough separation experiments are carried out for NIIC-20-Pr (Pr = propyleneglycol) using different C3H6/C2H4 and C3H8/C3H6 gas mixtures. The productivity of ethylene ranges from 2.60 to 2.94 mol center dot kg-1, the propylene productivity is 0.56 mol kg-1. Given the remarkable fundamental adsorption characteristics, the NIIC-20-G porous materials should be considered among the best solutions for efficient and economically viable separation of industrially important gas mixtures.

Correction for 'Confinement of Cd(II) by 2,2'-bipyridyl: control of structural transformations and porosity in perfluorinated biphenyldicarboxylate MOFs' by Pavel V. Burlak et al., Dalton Trans., 2026, https://doi.org/10.1039/d5dt02607e.

Cadmium(II) can form complexes with coordination numbers 6 and 7, which makes them labile, especially with relatively weak ligands like perfluorinated carboxylates. Confining the coordination environment with chelating ligands such as 2,2'-bipyridyl (2,2'-bpy) is a promising approach to obtain complexes with more predictable geometry and stability. Using this strategy, MOFs with anions of octafluorobiphenyldicarboxylic acid (H2oFbpdc) were successfully synthesized in different alcohols. Compound [Cd(2,2'-bpy)(oFbpdc)]·CH3OH (1·MeOH) exhibits a 3D framework, whereas the other phases [Cd(2,2'-bpy)(oFbpdc)]·G (2·G, G = EtOH, iPrOH, tBuOH) adopt a layered structure. Thermal activation of all phases results in guest removal, yielding the non-porous phase [Cd(2,2'-bpy)(oFbpdc)] (2). Despite its non-porous nature, 2 undergoes a structural transformation upon CO2 adsorption into an open form with a specific surface area of 237 m2 g-1. This transformed phase shows good adsorption selectivity for binary C2H2/CH4 and CO2/CH4 mixtures.

Lanthanide metal-organic frameworks combine the luminescent properties of rare earth elements with the structural tunability of molecular frameworks, making them ideal for multifunctional applications, such as luminescence sensing and gas separation. Herein, we report the synthesis of a red luminescent microporous Eu-MOF {[Eu2(H2O)L3]·3H2O}n using 1,2,5-thiadiazole-3,4-dicarboxylic acid (H2L) as the sole ligand. The H2L ligand features an effective antenna effect for energy transfer and structural rigidity, enabling the formation of a robust microporous framework. Detailed structural analysis revealed its highly ordered microporosity. The Eu-MOF exhibited excellent luminescence sensing performance for detecting nitrofuran antibiotics, including nitrofurantoin (NFN) and nitrofurazone (NTZ), demonstrating high selectivity, low detection limits, and short sensing response time (both within 6 s). Furthermore, the microporous structure of Eu-MOF endowed it with exceptional adsorption properties, enabling effective methane-acetylene separation.

Two new Tb(iii) metal-organic frameworks with an aliphatic bis-hydroxamate linker have been synthesized and structurally characterized. The title compounds have [Tb2(H2O)2(OAc)2(L)2]2Solv formulae, where L2- is a deprotonated form of 1,4-dihydroxy-3,3,6,6-tetramethylpiperazine-2,5-dione and Solv is N,N-dimethylacetamide or ethanol. Both compounds possess layered sql-type structures and appear to be solvatomorphic crystal phases, but with a significant change in the pore volume fraction from 35% for the DMA-based structure down to 23% for the EtOH-based one. The activation of the ethanol-based compound led to a porous network demonstrating hysteretic adsorption of carbon dioxide with a BET surface area of 493 m2 g-1. A narrow-banded emission in the green region, typical for Tb(iii)-based metal-organic complexes, was found for both obtained compounds with ca. 1% photoluminescence quantum yields, showing an ability of the first MOF-related example of a non-aromatic bis-hydroxamate strut presented herein to sensitize the phosphorescence of Tb(iii) ions.

Four new porous homochiral metal–organic frameworks (MOFs), [M2(camph)2(bpa)]∙Solv (M = Co(II), Ni(II), Cu(II) and Zn(II)), based on (+)-camphoric acid (H2camph) and 1,2-bis(4-pyridyl)ethane (bpa) were synthesized and characterized. The crystal structures of [Ni2(camph)2(bpa)] and [Zn2(camph)2(bpa)] were established by single-crystal X-ray diffraction analysis. Powder X-ray data prove the phase purity and isostructural nature of all four compounds. The thermal stability of [M2(camph)2(bpa)] was found to depend on the electronic configuration, as well as on the redox properties of the metal cation, and varied from 225 °C (M = Zn2+) to 375 °C (M = Ni2+). The reversible, solvent-induced sponge-like dynamics of the coordination frameworks was thoroughly investigated. Changes in the positions of reflexes, related to the length of the flexible bpa linker, were observed by powder XRD, pointing to transitions between an open-framework phase and a squeezed, non-porous phase in a crystal-to-crystal manner, while the integrity and connectivity of the coordination network were maintained. Size-selective adsorption from a benzene–cyclohexane 1:1 mixture on [Zn2(camph)2(bpa)] was studied by 1H NMR analysis. The benzene-favorable composition of guest molecules (C6H6:C6H12 = 5:1) occluded within the host crystalline sponge revealed a preferable adsorption affinity towards smaller benzene compared with larger cyclohexane. High framework stability in various solvents, as well as successful molecular separation in the liquid state, validates the potential utilization of chiral porous metal(II) camphorate MOFs in important stereoselective applications.

Creating holes in single-walled carbon nanotubes and shortening the encapsulated red phosphorus chains improves lithium accommodation in the nanomaterial.

Three new three-dimensional (3D) metal-organic frameworks [M2(ttdc)2(dabco)] (M = Zn(II), 1-Zn; Cu(II), 1-Cu; and Zn/Cu, 1-ZnCu) based on thieno[3,2-b]thiophene-2,5-dicarboxylate (ttdc2-) were synthesized and characterized by a combination of physicochemical methods (single crystal X-ray diffraction, powder X-ray diffraction, chemical and thermogravimetric analyses and IR spectroscopy). 1-Cu demonstrated permanent porosity (Vpore = 0.790 cm3 g-1 and SBET = 1725 m2 g-1) and significant CO2, CH4, C2H2, C2H4 and C2H6 gas uptakes under ambient conditions. The adsorption selectivities for gas mixtures, calculated by IAST, were 10.8 (10.7), 14.6 (9.4), 1.7 (1.6) and 1.5 (1.6) for the equimolar gas mixture compositions CO2/N2, C2H6/CH4, C2H6/C2H4 and C2H6/C2H2 at 1 bar and 273 K (298 K), respectively. The mixed-metal compound 1-ZnCu was prepared by a crystal-to-crystal ion exchange metathesis reaction from 1-Zn with a 52% degree of ion substitution, confirmed by energy-dispersive X-ray spectroscopy, optical microscopy and single crystal X-ray diffraction analysis.

The separation of light alkanes is one of the most important tasks for modern industry due to the widespread use of ethane and propane as chemical feedstocks. Their extraction from natural gas is a challenging task and is now carried out by cryogenic distillation at a limited number of plants around the world. The development of new materials for adsorption separation is therefore important. Among the different types of adsorbents, metal-organic frameworks (MOFs) are one of the most interesting due to their infinite design possibilities. Here we present a highly porous perfluorinated MOF [Sc(OH)(1,3-tFbdc)] (1,1,3-tFbdc2--1,3-C6F4(COO)2 2- tetrafluoroisophthalate linker) with a BET surface area greater than 1000 m center dot g-1 and its ability to separate light alkanes was investigated. The ability of 1 to separate light hydrocarbons at 0 and 25 degrees C is demonstrated by IAST calculation of selectivity factors as well as by dynamic breakthrough experiments. The role of fluorine substituents within the organic linker of MOF 1 in gas adsorption is revealed by quantum chemical calculations.

New manganese(II) and nickel(II) 1-D zigzag coordination polymers [M 2+ (pQ 2− )·2(solv)] n (M 2+ = Mn 2+ , solv = N,N’-dimethylacetamide ( 1 ) and M = Ni 2+ , solv = N,N’-dimethylformamide ( 2 ); pQ 2− - dianionic form of 2,5-di-hydroxy-3,6-di- tert -butyl-para-quinone) have been synthesized and characterized. Both compounds 1 and 2 are isomorphic. Their physicochemical properties such as thermal stability, gas sorption, redox and magnetic properties are described.

A synthesis procedure for composite precursors of the composition yttrium-stabilized zirconia nanoparticles – 2,2,6,6-tetramethyl-3,5-heptandionato-hafnium(IV) is developed. The thermal behavior of the synthesized composites is studied by the complex thermal analysis up to 600 °C in a wide concentration range. Main components of thermolysis products are determined by the energy-dispersive X-ray (EDX) analysis. Features are revealed in TG curves for all compositions in the temperature range of 310-410 °C. From the IR, XPS, and EDX data it is found that the observed effects are due to low-temperature decomposition of a small part of the volatile metal-organic precursor irreversibly absorbed on the surface of nanoparticles. A hypothesis is put forward that irreversible adsorption is caused by Lewis acid centers on the surface of nanoparticles. The obtained information about the thermal properties of composite precursorscan facilitate the development of methods to control nanoparticle concentrations in the coating formed.

Here, we present a series of Zn(II) and Co(II) coordination polymers containing two types of ligands: sterically rigid terephthalate derivatives (bdc-NO22- and bdc-Br2-) and flexible bis(2-methylimidazolyl)propane (bmip). The combination of two types of ligands allowed us to obtain and characterize both single and mixed-metal compounds by single crystal and powder X-ray diffraction, FT-IR, and elemental analysis. These 4-fold interpenetrated frameworks have a diamond topology and do not reveal any structural transformations despite the presence of a flexible ligand. Luminescence spectra for all the Zn-containing compounds were recorded. All the compounds exhibit a strong dependence of emission maxima on excitation wavelength, which is characteristic of the bmip ligand and is enhanced in coordination polymers. Compound [Zn(bdc-Br)(bmip)] demonstrates bright luminescence with a high quantum yield of 39%. Mixed-metal Zn(II)/Co(II) compounds have redshifted luminescence in comparison to [Zn(bdc-NO2)(bmip)] and compound [Zn0.6Co0.4(bdc-NO2)(bmip)] is characterized by near white emission under 460 nm excitation.

Heavy metal ions and antibiotic contamination have become a major environmental concern worldwide. The development of efficient recognition strategies of these pollutants at ultra-low concentrations in aqueous solutions as well as the elucidation of the intrinsic sensing mechanism are challenging tasks. In this work, unique luminescent Ln-MOF materials (NIIC-3-Ln) were assembled by rational ligand design. Among them, NIIC-3-Tb demonstrated highly selective luminescence quenching response toward Hg2+ and sulfadiazine (SDI) at subnanomolar concentrations in less than 7 s. In addition, a Hg2+ sensing mechanism through chelation was proposed on the basis of single-crystal X-ray diffraction analysis and Hg2+ adsorption study. The interaction mechanism of NIIC-3-Tb with SDI was revealed using a newly developed approach involving a (TD-)DFT based quantification of the charge transfer of a MOF-analyte supramolecular complex model in the ground and excited states. Effect of ultrasonic treatment on the surface morphology important for MOF sensing performance was revealed by gas adsorption experiments. The presented results indicate that NIIC-3-Ln is not only an advanced sensing material for the efficient detection of Hg2+ and SDI at ultra-low concentrations, but also opens up a new approach to study the sensing mechanism at the molecular level at ultra-low concentrations.

Разработан метод синтеза композитных прекурсоров состава «наночастицы оксида циркония, стабилизированного иттрием - 2,2,6,6- тетраметил-3,5-гептандионато-гафний (IV)». Методом комплексного термического анализа изучено термическое поведение синтезированных композитов до 600 °С в широком концентрационном интервале. Продукты термолиза проанализированы на основные компоненты методом энергодисперсионного анализа. Для всех составов на кривых ТГ выявлены особенности в интервале температур 310-410 °С. На основании данных ИК-спектроскопии, РФЭС и ЭДС установлено, что наблюдаемые эффекты связаны с низкотемпературным разложением небольшой части летучего металлоорганического прекурсора необратимо адсорбировавшегося на поверхности наночастиц. Высказана гипотеза, что необратимая адсорбция связана с кислотными Льюисовскими центрами на поверхности наночастиц. Полученная информация о термических свойствах композитных прекурсоров позволит разработать методы управления концентрацией наночастиц в формируемом покрытии.

Two new metal–organic frameworks based on highly flexible 1,4-diazabicyclo[2.2.2]octane N,N′-dioxide (odabco) ligands were successfully synthesized and characterized. Their crystallographic formulae are [M(DMF)2(odabco)2](ClO4)2·dioxane, where M2+ = Co2+ (1) and Ni2+ (2), and DMF is N,N-dimethylformamide. The title compounds possess cationic 2D coordination networks filled with perchlorate anions and dioxane solvent molecules in the interlayer space, with 20% solvent accessible volume. Carbon dioxide adsorption measurements for desolvated samples 1a and 2a gave 511 m2/g and 377 m2/g specific surface areas, respectively, revealing the first example of gas adsorption properties in the structure based on a flexible odabco bridge, despite the presence of large counteranions within the positively charged network. Magnetization measurements for 1, 1a, 2 and 2a reveal their paramagnetic nature to be in a reasonable agreement with crystal structures, and almost no solvent dependence of the magnetization characteristics. A decrease in the effective magnetic moment observed at low temperatures is attributed mostly to zero-field level-splitting in the octahedral Ni2+ and Co2+ ions.

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

A series of MIL-101-L compounds (L = 4,4′-bipyridyl, pyrazine, piperazine, 1,4-diaza[2.2.2]bicyclooctane, and ethylenediamine) was synthesized using the post-synthetic coordination modification of mesoporous chromium( iii ) terephthalate MIL-101. These compounds contain basic sites and are capable of exhibiting catalytic activity in the Henry nitroaldol condensation reaction with high selectivity. Compounds MIL-101-Sal-M (M = Ni, Cr, Zr, Co) containing the salen complexes grafted onto the framework surface were prepared using the covalent post-synthetic modification methods. These compounds exhibit catalytic activity in the addition of carbon dioxide to propylene oxide in quantitative yield in the presence of a cocatalyst. The results obtained confirm that the post-synthetic modification of porous metal-organic frameworks is an efficient approach for preparing heterogeneous catalysts based on the known homogeneous catalysts.

Hydrogen-bonded organic frameworks (HOFs) possessing high crystallinity, simple synthetic procedure and easy regeneration provide high efficiency as multifunctional systems, including applications as proton conductors. Porphyrinylphosphonates having acidic moieties, which can form multiple hydrogen bonds, together with tunable physical-chemical properties of a macrocycle may significantly improve the proton conductivity of such materials. Herein, the synthesis, characterization and proton-conducting properties of a novel anionic HOF based on a new complex of palladium(II) with meso-tetrakis(4-(phosphonatophenyl))porphyrin, HOF-IPCE-1Pd, are reported. Directed structural transformation of the framework by the exchange of dimethylammonium counterions for ammonium cations along with the absorption of ammonia and water molecules led to the formation of a more hydrolytically stable structure of HOF-IPCE-1Pd-NH3, demonstrating the proton conductivity of 1.27 × 10-3 S cm-1 at 85 °C and 85% RH, which is one of the highest among all known HOFs based on porphyrins. It is noteworthy that the reversible absorbance of water/ammonia molecules preserves the crystal structure of HOF-IPCE-1Pd-NH3.

Five new metal–organic frameworks based on Mn(II) and 2,2′-bithiophen-5,5′-dicarboxylate (btdc2–) with various chelating N-donor ligands (2,2′-bipyridyl = bpy; 5,5′-dimethyl-2,2′-bipyridyl = 5,5′-dmbpy; 4,4′-dimethyl-2,2′-bipyridyl = 4,4′-dmbpy) [Mn3(btdc)3(bpy)2]·4DMF, 1; [Mn3(btdc)3(5,5′-dmbpy)2]·5DMF, 2; [Mn(btdc)(4,4;-dmbpy)], 3; [Mn2(btdc)2(bpy)(dmf)]·0.5DMF, 4; [Mn2(btdc)2(5,5′-dmbpy)(dmf)]·DMF, 5 (dmf, DMF = N,N-dimethylformamide) have been synthesized, and their crystal structure has been established using single-crystal X-ray diffraction analysis (XRD). The chemical and phase purities of Compounds 1–3 have been confirmed via powder X-ray diffraction, thermogravimetric, and chemical analyses as well as IR spectroscopy. The influence of the bulkiness of the chelating N-donor ligand on the dimensionality and structure of the coordination polymer has been analyzed, and the decrease in the framework dimensionality, as well as the secondary building unit’s nuclearity and connectivity, has been observed for bulkier ligands. For three-dimensional (3D) coordination polymer 1, the textural and gas adsorption properties have been studied, revealing noticeable ideal adsorbed solution theory (IAST) CO2/N2 and CO2/CO selectivity factors (31.0 at 273 K and 19.1 at 298 K and 25.7 at 273 K and 17.0 at 298 K, respectively, for the equimolar composition and the total pressure of 1 bar). Moreover, significant adsorption selectivity for binary C2–C1 hydrocarbons mixtures (33.4 and 24.9 for C2H6/CH4, 24.8 and 17.7 for C2H4/CH4, 29.3 and 19.1 for C2H2/CH4 at 273 K and 298 K, respectively, for the equimolar composition and the total pressure of 1 bar) has been observed, making it possible to separate on 1 natural, shale, and associated petroleum gas into valuable individual components. The ability of Compound 1 to separate benzene and cyclohexane in a vapor phase has also been analyzed based on the adsorption isotherms of individual components measured at 298 K. The preferable adsorption of C6H6 over C6H12 by 1 at high vapor pressures (VB/VCH = 1.36) can be explained by the existence of multiple van der Waals interactions between guest benzene molecules and the metal–organic host revealed by the XRD analysis of 1 immersed in pure benzene for several days (1≅2C6H6). Interestingly, at low vapor pressures, an inversed behavior of 1 with preferable adsorption of C6H12 over C6H6 (KCH/KB = 6.33) was observed; this is a very rare phenomenon. Moreover, magnetic properties (the temperature-dependent molar magnetic susceptibility, χp(T) and effective magnetic moments, μeff(T), as well as the field-dependent magnetization, M(H)) have been studied for Compounds 1–3, revealing paramagnetic behavior consistent with their crystal structure.

Министерство науки и высшего образования Российской Федерации Российское химическое общество им.Д.И.Менделеева Секция по химической термодинамике и термохимии Научного совета РАН по физической химии Сибирское Отделение Российской Академии Наук Институт неорганической химии им.А.В.Николаева СО РАН