Cobalt(II) coordination polymers constructed from bis(N-pyrid-3-ylmethyl)adipoamide and polycarboxylic acids: reversible structural transformation upon proton delivery and removal

Hydrothermal reactions of cobalt(II) salts and bis(N-pyrid-3-ylmethyl)adipoamide (L) with various polycarboxylic acids in water and NaOH solutions afforded {[Co(L)0.5(1,3,5-HBTC)(H2O)]·H2O}n (1,3,5-H3BTC = benzene-1,3,5-tricarboxylic acid), 1, {[Co1.5(L)1.5(1,3,5-BTC)(H2O)4]·4H2O}n, 2, [Co(L)(5-tert-IPA)(H2O)2]n (5-tert-H2IPA = 5-tert-butylbenzene-1,3-dicarboxylic...

Gas-Dependent Reversible Structural and Magnetic Transformation between Two Ladder Compounds

We report reversible structural transformation that occurs in two ladder compounds: Cu2CO3(ClO4)2(NH3)6 (1) and Cu2CO3(ClO4)2(NH3)5(H2O) (2), when they are exposed to gaseous vapors. The ladder structures of both 1 and 2 consist of two Cu2+ ions and one CO32− ion. In 1, the Cu2+ ions are coordinated by three NH3 molecules on each side, while those in 2 are coordinated by three NH3 molecules on one side, and two NH3 molecules and one H2O molecule on the other side. We demonstrated reversible transformation of 1 and 2 via the exposure of 1 to H2O vapor and the exposure of 2 to NH3 vapor using a simple bench-scale method. The minor structural change observed led to a significant difference in physical properties, which we observed using several methods.

Pressure-induced amorphization and existence of molecular and polymeric amorphous forms in dense SO2

We report here the pressure-induced amorphization and reversible structural transformation between two amorphous forms of SO2: molecular amorphous and polymeric amorphous, with the transition found at 26 GPa over a broad temperature regime, 77 K to 300 K. The transformation was observed by both Raman spectroscopy and X-ray diffraction in a diamond anvil cell. The results were corroborated by ab initio molecular dynamics simulations, where both forward and reverse transitions were detected, opening a window to detailed analysis of the respective local structures. The high-pressure polymeric amorphous form was found to consist mainly of disordered polymeric chains made of three-coordinated sulfur atoms connected via oxygen atoms, with few residual intact molecules. This study provides an example of polyamorphism in a system consisting of simple molecules with multiple bonds.

Structural diversity and modification in Ni(ii) coordination polymers: a peculiar phenomenon of reversible structural transformation between a 1D ladder and 2D layer

The coordination of 5-tert-IPA2− ligands, the relaxation of the interdigitated 2D net and the breaking and connecting of the bis-pyridyl-bis-amide ligand demonstrate the peculiar reversible structural transformation between a 1D ladder and 2D layer.

One-dimensional chains based on linear tetranuclear copper(i) units: reversible structural transformation and luminescence change

Two extended metal chains based on linear tetracopper units are reported, in which the bromide complex undergoes reversible structural transformation and luminescence change.

Dynamic metal–organic frameworks for the separation of hydrogen isotopes

Reversible structural transformation along with breathing effect or gate-opening phenomena in some dynamic MOFs provide opportunity to operate or to enhance kinetic quantum sieving (KQS) for hydrogen isotope separation.

s-Block metal ions induce structural transformations between figure-eight and double trefoil knots

The presence or absence of s-block metal ions induces reversible structural transformation of molecular knots.