Complexation of Tolane by Fluorinated Organomercurials—Structures and Luminescence Properties of an Unusual Class of Supramolecular π-Coordination Polymers

The interaction of the Hg(II) derivatives bis(pentafluoro)phenyl mercury (1), (pentafluoro)phenyl mercury chloride (2) and trimeric perfluoro-ortho-phenylene mercury (3) with tolane (diphenylacetylene) in CH₂Cl₂ leads to the formation of [1·tolane], [2 ₂·tolane], and [3·tolane·CH₂Cl₂]. These adducts have been characterized by elemental analysis, X-ray crystallography, and luminescence spectroscopy. In the solid state of these adducts, the tolane molecules interact with the molecules of 1, 2 and 3 via secondary Hg–π interactions and arene–fluoroarene interactions. As a result of an external mercury heavy atom effect, adducts [1·tolane] and [2 ₂·tolane] are phosphorescent at room temperature.     

Structural Basis for Intumescence – Part III – Thermal Degradation Study of Intumescent Polymers Containing Spirophosphorus Moiety in the Backbone

3,9-Dichloro-2,4,8,10-tetraoxo-3,9-disphosphaspiro-[5.5]-undecane-3,9-dioxide (spiro) was melt condensed with structurally different dihydric phenols to form poly aromatic spirophosphates. The thermal volatilization analysis showed eruptive release of gases above 300°C and the temperature region of release depends on the nature of the aromatic units incorporated in the polymer backbone. The thermal degradation in nitrogen atmosphere indicated the formation of phenol, substituted phenols, aromatics, alkyl and alkenyl substituted aromatics and condensed aromatics like azulenes, indanes and fluorenes. The source for the formation of these products is the spiropentadiene released from the spiro unit during degradation.     

Syntheses,Crystal Structures and Properties of Two Supramolecular Coordination Polymers with 2,6-Pyridinedicarboxylic Acids and 4,4′-Bis(imidazolyl)biphenyl

Two supramolecular coordination polymers, [Cu(PDA)(4,4′-bibp)]_n (1) and [Zn(PDA)(4,4′-bibp)]_n (2) (PDA = 2,6-pyridinedicarboxylic acid and 4,4′-bibp = 4,4′-bis(imidazolyl)biphenyl), have been obtained under hydrothermal conditions. The two polymers were characterized by elemental analysis, IR spectroscopy and single-crystal X-ray diffraction analysis. The X-ray single crystal analysis revealed that two complexes exhibit different supramolecular architectures. The photocatalytic studies indicate complex 1 is a good candidate for the photocatalytic degradation of methylene blue, rhodamine B and methylene violet. The photoluminescence behaviour of complex 2 was also discussed.     

Capacity Fade Analysis of a Battery/Super Capacitor Hybrid and a Battery under Pulse Loads – Full Cell Studies

A detailed analysis of the capacity fade of a battery/supercapacitor hybrid and a battery alone has been carried out at 55 °C by discharging them at three different pulse rates. The applied peak current amplitudes were 5C (7 A), 3C (4.2 A), and 1C (1.4 A), respectively. The results indicated that for hybrids the pulse discharge run time was extended for all pulse discharge rates. The ohmic resistances estimated as a function of the pulse discharge rates were smaller for hybrids when compared with those for batteries. The variation of the ohmic resistance under pulse discharge with cycling, irrespective of the pulse discharge rate was smaller for hybrids than that for the batteries. The batteries and hybrids cycled at the lowest pulse discharge rate (high pulse discharge time) have larger capacity fade when compared with the capacity fade of the batteries and the hybrids discharged using higher discharge rates (low pulse discharge time). Impedance, cyclic voltammogram, and the rate capability studies were carried out on batteries cycled alone and on batteries cycled as part of the hybrid. The battery showed larger increase in the interfacial impedance with cycling when compared with the hybrid system.