Photo- and Stress-Induced Bending of (E)-1,2-Bis(pyridinium-4-yl)ethene Dinitrate Crystals.

We report on the elastic and photodynamic properties of (E)-1,2-bis(pyridinium-4-yl)ethene dinitrate [HEbpe](NO), whose needle-like crystals can be reversibly deformed by applying external mechanical stress. The macro-scale mechanical properties of [HEbpe](NO) crystals were quantified by a three-point bending test, which gave a stress-strain curve with an elastic modulus of 1.18 GPa, and its values are lower than those of other flexible elastic organic crystals.

Cooperative Spin-State Switching and Vapochromism of Mononuclear Ni(II) Complexes by Pyridine Coordination/Decoordination.

Two mononuclear Ni(II) complexes ( and ) have been found to display color changes upon coordination/decoordination of pyridine, resulting in their structural transformation between square-planar and octahedral geometries as well as a change in their spin state. Compound changes between red () and yellow () upon exposure to or elimination of pyridine, while undergoes a two-step transformation, changing orange ( = 0) ⇄ gray ( = 1) → yellow ( = 1) depending on the reaction time. The first step ( → ) takes less than 45 min, which is significantly faster than the previously reported reaction time of 1 day for a Ni(II) complex/pyridine vapor system.

Nanotubule inclusion in the channels formed by a six-fold interpenetrated, triperiodic framework.

When reacted together with uranyl ions under solvo-hydrothermal conditions, a bis(pyridiniumcarboxylate) zwitterion (L) and tricarballylic acid (Htca) give the complex [NH][UO(L)][UO(tca)]·2HO (1). The two ligands are segregated into different units, an anionic nanotubule for tca and a six-fold interpenetrated cationic framework with topology for L. The entangled framework defines large channels which contain the square-profile nanotubules.

Thermosalient effect of a naphthalene diimide and tetrachlorocobaltate hybrid and changes of color and magnetic properties by ammonia vapor.

An organic-inorganic hybrid metal halide (OIMH), namely the electron-deficient naphthalene diimide (NDI) and [CoCl] hybrid (1), showed potential as a sensor for ammonia and amines, in addition to magnetic changes upon vapochromism. Crystal 1 exhibited thermosalient behavior such as leaping and movement, at around 130 °C, which could be explained to be associated with the removal of water molecules from the crystal lattice as shown by TGA and DSC. Compound 1 changed from green to black within 5 minutes when exposed to ammonia vapor, which was attributed to the radical formation in the NDI moiety as evidenced by ESR, and this phenomenon was preserved even when other mono- and di-alkylamines were applied.

Woven, Polycatenated, or Cage Structures: Effect of Modulation of Ligand Curvature in Heteroleptic Uranyl Ion Complexes.

Combining the flexible zwitterionic dicarboxylate 4,4'-bis(2-carboxylatoethyl)-4,4'-bipyridinium (L) and the anionic dicarboxylate ligands isophthalate (ipht) and 1,2-, 1,3-, or 1,4-phenylenediacetate (1,2-, 1,3-, and 1,4-pda), of varying shape and curvature, has allowed isolation of five uranyl ion complexes by synthesis under solvo-hydrothermal conditions. [(UO)(L)(ipht)] () and [(UO)(L)(1,2-pda)]·2HO () have the same stoichiometry, and both crystallize as monoperiodic coordination polymers containing two uranyl-(anionic carboxylate) strands united by L linkers into a wide ribbon, all ligands being in the divergent conformation. Complex , [(UO)(L)(1,3-pda)]·0.

Flexible Aliphatic Diammonioacetates as Zwitterionic Ligands in UO Complexes: Diverse Topologies and Interpenetrated Structures.

''-Tetramethylethane-1,2-diammonioacetate (L1) and ''-tetramethylpropane-1,3-diammonioacetate (L2) are two flexible zwitterionic dicarboxylates which have been used as ligands for the uranyl ion, 12 complexes having been obtained from their coupling to diverse anions, mostly anionic polycarboxylates, or oxo, hydroxo and chlorido donors. The protonated zwitterion is a simple counterion in [HL1][UO(2,6-pydc)] (), where 2,6-pydc is 2,6-pyridinedicarboxylate, but it is deprotonated and coordinated in all the other complexes. [(UO)(L2)(2,4-pydcH)] (), where 2,4-pydc is 2,4-pyridinedicarboxylate, is a discrete, binuclear complex due to the terminal nature of the partially deprotonated anionic ligands.

Experimental Insight into the Thermodynamics of the Dissolution of Electrolytes in Room-Temperature Ionic Liquids: From the Mass Action Law to the Absolute Standard Chemical Potential of a Proton.

Room-temperature ionic liquids (ILs) are a class of nonaqueous solvents that have expanded the realm of modern chemistry, drawing increasing interest over the last few decades, not only in terms of their own unique physical chemistry but also in many applications including organic synthesis, electrochemistry, and biological systems, wherein charged solutes (i.e., electrolytes) often play vital roles.

Aerosol assisted fabrication of two dimensional ZnO island arrays and honeycomb patterns with identical lattice structures.

Two dimensional island arrays and honeycomb patterns consisting of ZnO nanocrystal clusters were fabricated on predefined TiO(2) seed patterns prepared by vacuum free, aerosol assisted wet-chemical synthesis. The TiO(2) seed patterns were prepared by applying an aerosol of a water soluble titanium complex on hexagonally close-packed polystyrene bead arrays for different lengths of time. Scanning electron microscopy revealed that a dot array grows into a honeycomb shape as increasing amounts of the precursor were deposited.

Configuration-specific synthesis of the facial and meridional isomers of tris(8-hydroxyquinolinate)aluminum (Alq3).

Treatment of AlO(OH) with 3 equiv of 8-hydroxyquinolinol in refluxing deionized water provided the meridional and facial isomers of tris(8-hydroxyquinolinate)aluminum (Alq3) with good yields as solid deposits after 1 and 90 h, respectively. X-ray diffraction and solid-state 13C NMR studies revealed that mer-Alq3 is formed in the early stage of the reaction and then gradually converts to fac-Alq3, which is thermodynamically less stable, although no existence of a catalyst substance is implied.