Role of NaCO as Nucleation Seeds to Accelerate the CO Uptake Kinetics of MgO-Based Sorbents.

There is an urgent need for inexpensive, functional materials that can capture and release CO under industrial conditions. In this context, MgO is a highly promising, earth-abundant CO sorbent. However, despite its favorable carbonation thermodynamics and potential for high gravimetric CO uptakes, MgO-based CO sorbents feature slow carbonation kinetics, limiting their CO uptake during typical industrial contact times.

Exploring the effect of pressure on the crystal structure and caloric properties of the molecular ionic hybrid [(CH)NOH][CoCl].

The hybrid metal halide [(CH)NOH]CoCl exhibits a first-order phase transition at ∼ 343 K. Its crystal structure and caloric properties respond significantly to moderate pressures (1-1000 bar), demonstrating potential for applications in emerging solid-state refrigeration technologies.

Ligand effects on gas adsorption in nanoporous phthalocyanine crystals.

X-ray diffraction is used to study the sorption of CO and NO in two phthalocyanine nanoporous crystals (PNCs) with 4,4' bipyridine or 4,4' bipyrimidine coordinated to open Co sites, demonstrating how the coordinated ligands influence the gas sorption properties and structures of the PNCs.

A Scalable Robust Microporous Al-MOF for Post-Combustion Carbon Capture.

Herein, a robust microporous aluminum tetracarboxylate framework, MIL-120(Al)-AP, (MIL, AP: Institute Lavoisier and Ambient Pressure synthesis, respectively) is reported, which exhibits high CO uptake (1.9 mmol g at 0.1 bar, 298 K).

Lattice response to the radiation damage of molecular crystals: radiation-induced versus thermal expansivity.

The interaction of intense synchrotron radiation with molecular crystals frequently modifies the crystal structure by breaking bonds, producing fragments and, hence, inducing disorder. Here, a second-rank tensor of radiation-induced lattice strain is proposed to characterize the structural susceptibility to radiation. Quantitative estimates are derived using a linear response approximation from experimental data collected on three materials Hg(NO)(PPh), Hg(CN)(PPh) and BiPh [PPh = triphenylphosphine, P(CH); Ph = phenyl, CH], and are compared with the corresponding thermal expansivities.

Empowering CO Eco-Refrigeration With Colossal Breathing-Caloric-Like Effects in MOF-508b.

Today, ≈20% of the electric consumption is devoted to refrigeration; while, ≈50% of the final energy is dedicated to heating applications. In this scenario, many cooling devices and heat-pumps are transitioning toward the use of CO as an eco-friendly refrigerant, favoring carbon circular economy. Nevertheless, CO still has some limitations, such as large operating pressures (70-150 bar) and a critical point at 31 °C, which compromises efficiency and increases technological complexity.

Which Ion Dominates the Temperature and Pressure Response of Halide Perovskites and Elpasolites?

Halide perovskites and elpasolites are key for optoelectronic applications due to their exceptional performance and adaptability. However, understanding their crucial elastic properties for synthesis and device operation remains limited. We performed temperature- and pressure-dependent synchrotron-based powder X-ray diffraction at low pressures (ambient to 0.

Reversible Pressure-Magnetic Modulation in a Tetrathiafulvalene-Based Dyad Piezochromic Dysprosium Single-Molecule Magnet.

The extreme sensitivity of trivalent lanthanide ions to crystal field variations led to the emergence of single-molecule magnetic switching under various stimuli. The use of pressure as an external stimulus instead of classic light irradiation, oxidation or any chemical reactions allows a fine tuning of the magnetic modulation. Here the well-known pure isotopically enriched [ Dy(tta) (L)]⋅C H ( Dy) Single-Molecule Magnet (SMM) (tta =2-2-thenoyltrifluoroacetonate and L=4,5-bis(propylthio)-tetrathiafulvalene-2-(2-pyridyl)benzimidazole-methyl-2-pyridine) was experimentally investigated by single-crystal diffraction and squid magnetometry under high applied pressures.

Incommensurate structures and radiation damage in RbVO and KVO mixed-valence vanadate fresnoites.

The structures and phase transitions to incommensurate structures in RbVO and KVO mixed-valence vanadate fresnoites are studied with synchrotron single-crystal diffraction at low temperatures and ambient pressure. Although mixed satellite reflections are absent, the modulated structure of KVO below 115 K is better described in (3 + 2)- than in (3 + 1)-dimensional space. The geometries of the VO and VO building units are rigid and it is mainly slight rotations of these polyhedra and small variation of the intermediate K-O distances that are modulated.

A new high temperature, high heating rate, low axial gradient capillary heater.

A new heater design, capable of fast heating and cooling to and from >1000°C, has been developed at the Swiss-Norwegian Beamlines, European Synchrotron Radiation Facility, France. The design uses a SiC head to distribute heat, and resistive SiN heat cartridges to provide heat.

The structure of a pentachromium(II) extended metal atom chain at 3 K: Cotton's conjecture proven.

We provide definitive experimental proof that the archetypal string-like compound [Cr(tpda)(NCS)] has alternating long and short Cr-Cr separations in the solid state, as conjectured by F. A. Cotton, rather than essentially equally spaced Cr atoms, as initially claimed (Htpda = ,-di(pyridin-2-yl)pyridine-2,6-diamine).

Pressure and guest-mediated pore shape modification in a small pore MOF to 1200 bar.

Guest-mediated pore-shape modification of the metal-organic framework, ScBDC upon adsorption of -pentane and isopentane is examined from 50-1200 bar. Rotation of the BDC linker responsible for the change in pore shape occurs at much lower pressures than previously reported, with distinct adsorption behaviour observed between pentane isomers.

Low-frequency lattice vibrations from atomic displacement parameters of α-FOX-7, a high energy density material.

Highly anharmonic thermal vibrations may serve as a source of structural instabilities resulting in phase transitions, chemical reactions and even the mechanical disintegration of a material. Ab initio calculations model thermal motion within a harmonic or sometimes quasi-harmonic approximation and must be complimented by experimental data on temperature-dependent vibrational frequencies. Here multi-temperature atomic displacement parameters (ADPs), derived from a single-crystal synchrotron diffraction experiment, are used to characterize low-frequency lattice vibrations in the α-FOX-7 layered structure.

FOX-7 high-energy-density material: thermal expansion and phase transitions revisited.

Variable-temperature single-crystal diffraction experiments treated with the Gandolfi method reveal the detailed temperature evolution of the unit-cell dimensions, structural transformations and the phase co-existence of the energetic material FOX-7. Two first-order phase transitions are observed accompanied by abrupt changes in volume and unit-cell dimensions. The thermal expansion is found to be linear for all three phases, albeit highly anisotropic.

On the resolution function for powder diffraction with area detectors.

In a powder diffraction experiment the resolution function defines the instrumental contribution to the peak widths as a function of the Bragg angle. The Caglioti formula is frequently applied to model the instrumental broadening and used in structural refinement. The parameters in the Caglioti formula are linked to physically meaningful parameters for most diffraction geometries.

Pressure-and temperature induced phase transitions, piezochromism, NLC behaviour and pressure controlled Jahn-Teller switching in a Cu-based framework.

single-crystal diffraction and spectroscopic techniques have been used to study a previously unreported Cu-framework bis[1-(4-pyridyl)butane-1,3-dione]copper(ii) (CuPyr-I). CuPyr-I was found to exhibit high-pressure and low-temperature phase transitions, piezochromism, negative linear compressibility, and a pressure induced Jahn-Teller switch, where the switching pressure was hydrostatic media dependent.

Encapsulated Nanodroplet Crystallization of Organic-Soluble Small Molecules.

Single-crystal X-ray diffraction analysis (SCXRD) constitutes a universal approach for the elucidation of molecular structure and the study of crystalline forms. However, the discovery of viable crystallization conditions remains both experimentally challenging and resource intensive in both time and the quantity of analyte(s). We report a robot-assisted, high-throughput method for the crystallization of organic-soluble small molecules in which we employ only micrograms of analyte per experiment.

Trigonal to Pentagonal Bipyramidal Coordination Switching in a Co(II) Single-Ion Magnet.

In molecular magnetism and single-ion magnets in particular, the observation of slow relaxation of the magnetization is intimately linked to the coordination environment of the metal center. Such systems typically have blocking temperatures well below that of liquid nitrogen, and therefore detailed magnetic characterization is usually carried out at very low temperatures. Despite this, there has been little advantage taken of ultralow temperature single-crystal X-ray diffraction techniques that could provide a full understanding of the crystal structure in the same temperature regime where slow magnetic relaxation occurs.

Reducing the background of ultra-low-temperature X-ray diffraction data through new methods and advanced materials.

New methods and advanced materials that significantly reduce the background when collecting single-crystal X-ray diffraction data at ultra-low temperatures using a closed-cycle helium refrigerator are presented here. These include a magnetically controlled internal beamstop and a separate internal collimator that together completely remove the scattering contribution to the background from the beryllium vacuum chamber. Additionally, a new radiation shield made from flexible graphite significantly reduces the background and maintains excellent thermal properties.