Metal-Organic Network-Forming Glasses

The crystal–liquid–glass phase transition of coordination polymers (CPs) and metal–organic frameworks (MOFs) offers attractive opportunities as a new class of amorphous materials. Unlike conventional glasses, coordination chemistry allows the utilization of rational design concepts to fine-tune the desired properties. Although the glassy state has been rare in CPs/MOFs, it exhibits diverse advantages complementary to their crystalline counterparts, including improved mass transport, optical properties, mechanical properties, and the ability to form grain-boundary-free monoliths. This Review discusses the current achievements in improving the understanding of anomalous phase transitions in CPs/MOFs. We elaborate on the criteria for classifying CP/MOF glasses and comprehensively discuss the three common strategies employed to obtain a glassy state. We include all CP/MOF glass research progress since its inception, discuss the current challenges, and express our perspective on future research directions

Efficacy of chronic neck pain self-treatment using press needles: a randomized controlled clinical trial

BackgroundChronic neck pain is common among Japanese individuals, but few receive treatment. This randomized controlled trial aimed to evaluate the efficacy of acupuncture using press needles in the self-treatment of chronic neck pain and preliminarily identify the characteristics of patients likely to benefit from this treatment.MethodsFifty participants with chronic neck pain were allocated to receive either press needle or placebo treatment for 3 weeks. The visual analogue scale (VAS) and motion-related VAS (M-VAS) scores for neck pain, Neck Disability Index score, and pressure pain threshold were measured at baseline, after the first session, at the end of the last session, and 1 week after the last session. Changes in the outcomes were analyzed using analysis of variance, and the relationships between the variables were evaluated using structural equation modeling.ResultsIntervention results as assessed by VAS score revealed no significant differences in the ANOVA. A between-groups comparison of M-VAS scores at the end of the last session and baseline showed a significant difference (press needle: −21.64 ± 4.47, placebo: −8.09 ± 3.81, p = 0.025, d = −0.65). Structural equation modeling revealed a significant pain-reducing effect of press needle treatment (β = −0.228, p = 0.049). Severity directly affected efficacy (β = −0.881, p < 0.001). Pain duration, baseline VAS and Neck Disability Index scores were variables explaining severity, while age and occupational computer use were factors affecting severity.ConclusionSelf-treatment with press needles for chronic neck pain did not significantly reduce the VAS score compared to placebo but reduced the motion-related pain as assessed by M-VAS score. A direct association was observed between pain severity and the effectiveness of press needles, and the impact of age and computer were indirectly linked by pain severity.Clinical Trial RegistrationIdentifier UMIN-CTR, UMIN000044078

Proton-conductive coordination polymer glass for solid-state anhydrous proton batteries

Designing solid-state electrolytes for proton batteries at moderate temperatures is challenging as most solid-state proton conductors suffer from poor moldability and thermal stability. Crystal–glass transformation of coordination polymers (CPs) and metal–organic frameworks (MOFs) via melt-quenching offers diverse accessibility to unique properties as well as processing abilities. Here, we synthesized a glassy-state CP, [Zn₃(H₂PO₄)₆(H₂O)₃](1, 2, 3-benzotriazole), that exhibited a low melting temperature (114 °C) and a high anhydrous single-ion proton conductivity (8.0 × 10⁻³ S cm⁻¹ at 120 °C). Converting crystalline CPs to their glassy-state counterparts via melt-quenching not only initiated an isotropic disordered domain that enhanced H⁺ dynamics, but also generated an immersive interface that was beneficial for solid electrolyte applications. Finally, we demonstrated the first example of a rechargeable all-solid-state H+ battery utilizing the new glassy-state CP, which exhibited a wide operating-temperature range of 25 to 110 °C

Synthesis of magnesium ZIF-8 from Mg(BH₄)₂.

Porous Mg(2-methyl imidazolate)2 (Mg-ZIF-8) was synthesised from Mg(BH4)2 as a precursor under an Ar atmosphere. It possesses an uncommon tetrahedral Mg(2+)-N coordination geometry that is stabilised by the formation of a framework, and it exhibits a Brunauer-Emmett-Teller surface area greater than 1800 m(2) g(-1)

(4-Carb­oxy-2-sulfonato­benzoato-κ2 O 1,O 2)bis­(1,10-phenanthroline-κ2 N,N′)manganese(II)

In the title complex, [Mn(C8H4O7S)(C12H8N2)2], the MnII atom is chelated by one 4-carb­oxy-2-sulfonato­benzoate anion and two phenathroline (phen) ligands in a distorted octa­hedral MnN4O2 geometry. The benzene ring of the 4-carb­oxy-2-sulfonato­benzoate anion is twisted with respect to the two phen ring systems at dihedral angles of 66.38 (9) and 53.56 (9)°. In the crystal, inter­molecular O—H⋯O and C—H⋯O hydrogen bonding links the mol­ecules into chains running parallel to [100]. Inter­molecular π–π stacking is also observed between parallel phen ring systems, the face-to-face distance being 3.432 (6) Å