Poly[bis(μ-purin-9-ido-κ2 N 7:N 9)zinc]

In the title compound, [Zn(C5H3N4)2], the ZnII cation is in a nearly regular tetra­hedral coordination by purinate ligands. Each purinate ligand chelates two ZnII cations through two imidazole N atoms of the purinate anion ligand, leading to the formation of a three-dimensional network

2,4,6-Triamino-1,3,5-triazine-1,3-diium aqua­penta­fluoridoaluminate

The title compound, (C3H8N6)[AlF5(H2O)], was obtained by solvothermal synthesis from the reaction of aluminium hydroxide, 1,3,5-triazine-2,4,6-triamine (melamine), aqueous HF and water at 323 K for 48 h. The structure consists of [AlF5(H2O)]2− octa­hedra and diprotonated melaminium cations. Cohesion is ensured by a three-dimensional network of hydrogen bonds

Purification of Propylene and Ethylene by a Robust Metal–Organic Framework Mediated by Host–Guest Interactions

From Wiley via Jisc Publications RouterHistory: received 2021-03-19, pub-electronic 2021-06-07Article version: VoRPublication status: PublishedFunder: Engineering and Physical Sciences Research Council; Id: http://dx.doi.org/10.13039/501100000266; Grant(s): EP/I011870, EP/R00661X/1, EP/S019367/1, EP/P025021/1, EP/P025498/1Funder: European Research Council; Id: http://dx.doi.org/10.13039/501100000781; Grant(s): 742401Abstract: Industrial purification of propylene and ethylene requires cryogenic distillation and selective hydrogenation over palladium catalysts to remove propane, ethane and/or trace amounts of acetylene. Here, we report the excellent separation of equimolar mixtures of propylene/propane and ethylene/ethane, and of a 1/100 mixture of acetylene/ethylene by a highly robust microporous material, MFM‐520, under dynamic conditions. In situ synchrotron single crystal X‐ray diffraction, inelastic neutron scattering and analysis of adsorption thermodynamic parameters reveal that a series of synergistic host–guest interactions involving hydrogen bonding and π⋅⋅⋅π stacking interactions underpin the cooperative binding of alkenes within the pore. Notably, the optimal pore geometry of the material enables selective accommodation of acetylene. The practical potential of this porous material has been demonstrated by fabricating mixed‐matrix membranes comprising MFM‐520, Matrimid and PIM‐1, and these exhibit not only a high permeability for propylene (≈1984 Barrer), but also a separation factor of 7.8 for an equimolar mixture of propylene/propane at 298 K

Fluoroaluminates of purine and DNA bases, adenine, guanine: [Hpur](2)center dot(AlF5), [Hade](3)center dot(AlF6)center dot 6.5H(2)O, [Hguan](3)center dot(Al3F12)

New purinium, adeninium and guaninium fluoroaluminates, [Hpur](2)center dot(AlF5), [Hade](3)center dot(AlF6)center dot 6.5H(2)O and [Hguan](3)center dot(Al3F12), are synthesized by microwave heating assisted hydrothermal synthesis at 120 degrees C or 190 degrees C. The crystallisation is difficult; all crystals of [Hpur](2)center dot(AlF6) and [Hade](3)center dot(AlF6)center dot 6.5H(2)O are very small while only a microcrystalline powder of [Hguan](3)center dot(Al3F12) is obtained. The structures are determined from crystal ([Hpur](2)center dot(AlF5) and [Hade](3)center dot(AlF6)center dot 6.5H(2)O) or powder ([Hguan](3)center dot Al3F12)) X-ray diffraction data. In [Hpur](2)center dot(AlF5), trans-chains of corner sharing octahedra lie along the c axis of the tetragonal cell (a = 18.997 (2) angstrom, c = 3.6980(4) angstrom, P4/n, Z = 4). In [Hade](3)center dot(AlF6)center dot 6.5H(2)O, the octahedral AlF6 units lie in (010) planes with water molecules. In [Hguan](3) (Al3F12), trimers of corner sharing octahedra are associated by opposite vertices along the c axis of the trigonal cell (a = 14.254(1) angstrom. c = 3.629(1) angstrom, P3, Z = 1). The purine, adenine and guanine amines are monoprotonated and lie between the preceding chains or layers. Hydrogen bonds between fluoride ions and amine groups of organic cations or, eventually, water molecules ensure the stability of the structures, together with N-H center dot center dot center dot O intermolecular bonds between guaninium cations in [Hguan](3)center dot(Al3F12). The N(7)H-amino and N(9)H-amino tautomeric forms of [Hade](+) are simultaneously found in [Hade](3)center dot(AlF6)center dot 6.5H(2)O. (C) 2010 Elsevier Masson SAS. All rights reserved.</p

Fluorinated MOF platform for selective removal and sensing of SO2 from flue gas and air

International audienceConventional SO 2 scrubbing agents, namely calcium oxide and zeolites, are often used to remove SO 2 using a strong or irreversible adsorption-based process. However, adsorbents capable of sensing and selectively capturing this toxic molecule in a reversible manner, with in-depth understanding of structure-property relationships, have been rarely explored. Here we report the selective removal and sensing of SO 2 using recently unveiled fluorinated metal-organic frameworks (MOFs). Mixed gas adsorption experiments were performed at low concentrations ranging from 250 p.p.m. to 7% of SO 2. Direct mixed gas column breakthrough and/or column desorption experiments revealed an unprecedented SO 2 affinity for KAUST-7 (NbOFFIVE-1-Ni) and KAUST-8 (AlFFIVE-1-Ni) MOFs. Furthermore, MOF-coated quartz crystal microbalance transducers were used to develop sensors with the ability to detect SO 2 at low concentrations ranging from 25 to 500 p.p.m

Ratiometric Nanothermometer Based on an Emissive Ln³⁺-Organic Framework

Luminescent thermometers working at the nanoscale with high spatial resolution, where the conventional methods are ineffective, have emerged over the last couple of years as a very active field of research. Lanthanide-based materials are among the most versatile thermal probes used in luminescent nanothermometers. Here, nanorods of metal organic framework Tb_0.99Eu_0.01(BDC)_1.5(H₂O)₂ (BDC = 1-4-benzendicarboxylate) have been prepared by the reverse microemulsion technique and characterized and their photoluminescence properties studied from room temperature to 318 K. Aqueous suspensions of these nanoparticles display an excellent performance as ratiometric luminescent nanothermometers in the physiological temperature (300–320 K) range