130 results match your criteria: "University of Manchester Oxford Road[Affiliation]"

Rare earth benzene tetraanion-bridged amidinate complexes.

Chem Sci

December 2024

Frontier Institute of Science and Technology, State Key Laboratory of Electrical Insulation and Power Equipment, MOE Key Laboratory for Nonequilibrium Synthesis of Condensed Matter, Xi'an Key Laboratory of Electronic Devices and Materials Chemistry and School of Chemistry, Xi'an Jiaotong University 99 Yanxiang Road Xi'an Shaanxi 710054 P. R. China

The benzene tetraanion-bridged rare earth inverse arene amidinate complexes [{Ln(κ:η-Piso)}(μ-η:η-CH)] (2-Ln, Ln = Gd, Tb, Dy, Y; Piso = {(NDipp)C Bu}, Dipp = CH Pr-2,6) were prepared by the reduction of parent Ln(iii) bis-amidinate halide precursors [Ln(Piso)X] (Ln = Tb, Dy; X = Cl, I) or [Ln(Piso)I] (Ln = Gd, Y) with 3 eq. KC in benzene, or by the reaction of the homoleptic Ln(ii) complexes [Ln(Piso)] (Ln = Tb, Dy) with 2 eq. KC in benzene.

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Nanocrystals are widely explored for a range of medical, imaging, sensing, and energy conversion applications. CdS nanocrystals have been reported as excellent photocatalysts, with thin film CdS also highly important in photovoltaic devices. To optimise properties of nanocrystals, control over phase, facet, and morphology are vital.

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Dysprosium single-molecule magnets (SMMs) with two mutually -anionic ligands have shown large crystal field (CF) splitting, giving record effective energy barriers to magnetic reversal ( ) and hysteresis temperatures ( ). However, these complexes tend to be bent, imposing a transverse field that reduces the purity of the projections of the CF states and promotes magnetic relaxation. A complex with only one charge-dense anionic ligand could have more pure CF states, and thus high and .

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We probe herein the fundamental factors that induce decoherence in ensembles of molecular magnetic materials. This is done by pulse Electron Paramagnetic Resonance measurements at X-band (∼9.6 GHz) on single crystals of Gd@Y(trensal) at 0.

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Selective hydrogenolysis of the Csp-O bond in the furan ring using hydride-proton pairs derived from hydrogen spillover.

Chem Sci

October 2024

Beijing National Laboratory for Molecular Sciences, CAS Laboratory of Colloid and Interface and Thermodynamics, CAS Research/Education Center for Excellence in Molecular Sciences, Center for Carbon Neutral Chemistry, Institute of Chemistry, Chinese Academy of Sciences Beijing 100190 China

Selective hydrogenolysis of biomass-derived furanic compounds is a promising approach for synthesizing aliphatic polyols by opening the furan ring. However, there remains a significant need for highly efficient catalysts that selectively target the Csp-O bond in the furan ring, as well as for a deeper understanding of the fundamental atomistic mechanisms behind these reactions. In this study, we present the use of Pt-Fe bimetallic catalysts supported on layered double hydroxides [PtFe /LDH] for the hydrogenolysis of furanic compounds into aliphatic alcohols, achieving over 90% selectivity toward diols and triols.

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The structural, self-assembly and binding properties of oligo-(phenylene-ethynylene) (OPE) rigid rods linked to squaramides (SQs) have been studied and correlated with rod length. In the solid-state, OPE-SQ conjugates form indefinite arrays of head-to-tail hydrogen bonded SQs, arrays that include both intra- and intermolecular hydrogen bonds. In dichloromethane solution, intramolecularly hydrogen bonded SQ chains show cooperative polarisation, an effect that increases with OPE-SQ length.

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Cryopreservation is crucial to fields including immune and stem cell therapies, reproductive technology, blood banking, regenerative medicine and across all biotechnology. During cryopreservation, cryoprotectants are essential to protect cells from the damage caused by exposure to freezing temperatures. The most common penetrating cryoprotectants, such as DMSO and glycerol do not give full recovery and have a cytotoxicity limit on the concentration which can be applied.

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This work reports the thermal and electron beam stabilities of a series of isostructural metal-organic frameworks (MOFs) of type MFM-300(M) (M = Al, Ga, In, Cr). MFM-300(Cr) was most stable under the electron beam, having an unusually high critical electron fluence of 1111 e Å while the Group 13 element MOFs were found to be less stable. Within Group 13, MFM-300(Al) had the highest critical electron fluence of 330 e Å, compared to 189 e Å and 147 e Å for the Ga and In MOFs, respectively.

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Non-viral gene delivery with cationic polymers/nanoparticles relies on iterative optimization of the carrier to achieve delivery. Here we demonstrate, instead, that precision engineering of cell surfaces to covalently capture a polyplex accelerates gene delivery within just 10 min of exposure. Azides were installed into cell-surface sialic acids, which enabled the rapid and selective recruitment of cyclooctyne-functional polyplexes, leading to increased delivery of fluorescent cargo, and also increased plasmid expression and siRNA knockdown.

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The wetting properties of carbon surfaces are important for a number of applications, including in electrochemistry. An under-studied area is the electrowetting properties of carbon materials, namely the sensitivity of wetting to an applied potential. In this work we explore the electrowetting behaviour of glassy carbon substrates and compare and contrast the observed response with our previous work using highly oriented pyrolytic graphite.

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The design and development of supported catalysts for the oxygen evolution reaction (OER) is a promising pathway to reducing iridium loading in proton exchange membrane water electrolysers. However, supported catalysts often suffer from poor activity and durability, particularly when deployed in membrane electrode assemblies. In this work, we deploy iridium coated hollow titanium dioxide particles as OER catalysts to achieve higher Ir mass activities than the leading commercial catalysts.

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Landmark advances in rare earth (RE) chemistry have shown that divalent complexes can be isolated with non-Aufbau 4f {5d/6s} electron configurations, facilitating remarkable bonding motifs and magnetic properties. We report a series of divalent bis-tethered arene complexes, [RE(NHAr )] (2RE; RE = Sc, Y, La, Sm, Eu, Tm, Yb; NHAr = {N(H)CH-2,6-(CH-2,4,6-Pr)}). Fluid solution EPR spectroscopy gives < 2.

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Bacteriophages are promising as therapeutics and biotechnological tools, but they also present a problem for routine and commercial bacterial cultures, where contamination must be avoided. Poly(carboxylic acids) have been reported to inhibit phages' ability to infect their bacterial hosts and hence offer an exciting route to discover additives to prevent infection. Their mechanism and limitations have not been explored.

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Computational simulation methods based on machine learned potentials (MLPs) promise to revolutionise shape prediction of flexible molecules in solution, but their widespread adoption has been limited by the way in which training data is generated. Here, we present an approach which allows the key conformational degrees of freedom to be properly represented in reference molecular datasets. MLPs trained on these datasets using a global descriptor scheme are generalisable in conformational space, providing quantum chemical accuracy for all conformers.

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We investigate actinide covalency effects in two [AnCp] (An = Th, U) complexes recently studied with pulsed electron paramagnetic resonance spectroscopy, using the Hyperion package to obtain relativistic hyperfine coupling constants from relativistic multiconfigurational wave functions. H and C HYSCORE simulations using the computed parameters show excellent agreement with the experimental data, highlighting the accuracy of modern relativistic ab initio methods. The extent of covalency indicated from the calculations on [ThCp] is in agreement with the original report based on traditional spectral fitting methods, while the covalency in [UCp] is found to be previously overestimated.

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We examine lanthanide (Ln)-ligand bonding in a family of early Ln complexes [Ln(Cp)] (1-Ln, Ln = La, Ce, Nd, Sm; Cp = CHBu-1,3) by pulsed electron paramagnetic resonance (EPR) methods, and provide the first characterization of 1-La and 1-Nd by single crystal XRD, multinuclear NMR, IR and UV/Vis/NIR spectroscopy. We measure electron spin and relaxation times of 12 and 0.2 μs (1-Nd), 89 and 1 μs (1-Ce) and 150 and 1.

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Understanding and controlling spin dynamics in organic dyes is of significant scientific and technological interest. The investigation of 2,5-dihydropyrrolo[4,3-]pyrrolo-1,4-dione derivatives (DPPs), one of the most widely used dyes in many fields, has so far been limited to closed-shell molecules. We present a comprehensive joint experimental and computational study of DPP derivatives covalently linked to two nitronyl nitroxide radicals (DPP-NN).

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Complexes of the form [U(η-arene)(BH)] where arene = CH; CHMe; CH-1,3,5-R (R = Et, iPr, Bu, Ph); CMe; and triphenylene (CH) were investigated towards an understanding of the nature of the uranium-arene interaction. Density functional theory (DFT) shows the interaction energy reflects the interplay between higher energy electron rich π-systems which drive electrostatic contributions, and lower energy electron poor π-systems which give rise to larger orbital contributions. The interaction is weak in all cases, which is consistent with the picture that emerges from a topological analysis of the electron density where metrics indicative of covalency show limited dependence on the nature of the ligand - the interaction is predominantly electrostatic in nature.

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Lipid nanoparticles have proved an attractive approach for drug delivery; however, the challenges of optimising formulation stability and increasing drug loading have limited progression. In this work, we investigate the role of unpegylated lipid surfactants (helper lipids) in nanoparticle formation and the effect of blending helper lipids with pegylated lipid surfactants on the formation and stability of lipid-based nanoparticles by nanoprecipitation. Furthermore, blends of unpegylated/pegylated lipid surfactants were examined for ability to accommodate higher drug loading formulations by means of a higher weight percentage (wt%) of drug relative to total mass of formulation components ( drug, surfactants and lipids).

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Diphosphonioalkylidene dianions have emerged as highly effective ligands for lanthanide and actinide ions, and the resulting formal metal-carbon double bonds have challenged and developed conventional thinking about f-element bond multiplicity and covalency. However, f-element-diphosphonioalkylidene complexes can be represented by several resonance forms that render their metal-carbon double bond status unclear. Here, we report an experimentally-validated C Nuclear Magnetic Resonance computational assessment of two cerium(iv)-diphosphonioalkylidene complexes, [Ce(BIPM)(ODipp)] (1, BIPM = {C(PPhNSiMe)}; Dipp = 2,6-diisopropylphenyl) and [Ce(BIPM)] (2).

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The coordination and organometallic chemistry of the f-elements, that is group 3, lanthanide, and actinide ions, supported by nitrogen ligands, amides, imides, and nitrides, has become well developed over many decades. In contrast, the corresponding f-element chemisty with the heavier pnictogen analogues phosphorus, arsenic, antimony, and bismuth has remained significantly underdeveloped, due largely to a lack of suitable synthetic methodologies and also the inherent hard(f-element)-soft(heavier pnictogen) acid-base mismatch, but has begun to flourish in recent years. Here, we review complexes containing chemical bonds between the f-elements and heavy pnictogens from phosphorus to bismuth that spans five decades of endeavour.

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Here we report the synthesis and structural characterization of four [7]rotaxanes formed by coordinating hybrid inorganic-organic [2]rotaxanes to a central {Ni} core. X-ray single crystal diffraction demonstrate that [7]rotaxanes are formed, with a range of conformations in the crystal. Small angle X-ray scattering supported by molecular dynamic simulations demonstrates that the large molecules are stable in solution and also show that the conformers present in solution are not those found in the crystal.

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Body temperature is an important indicator of human health. The traditional mercury and medical electronic thermometers have a slow response (≥1 min) and can not be worn for long to achieve continuous temperature monitoring due to their rigidity. In this work, we prepared a skin-core structure polyurethane (PU)/graphene encapsulated poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS) temperature-sensitive fiber in one step by combining wet spinning technology with impregnation technology.

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Ethnopharmacological Relevance: Puerarin (PUR) isolated from the root of Pueraria lobata (Willd.) Ohwi is considered as one of the main medicines to alleviate asthenic splenonephro-yang of diabetic nephropathy (DN). Whereas, the exact mechanism of Puerarin on diabetic nephropathy is still unclear.

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