Computational approaches to understanding reaction outcomes of organic processes in ionic liquids

This review considers how various computational methods have been applied to explain the changes in reaction outcome on moving from a molecular to an ionic liquid solvent. Initially, different conceptual approaches to modelling ionic liquids are discussed, followed by a consideration of the limitations and constraints of these approaches. A series of case studies demonstrating the utility of computational approaches to explain processes in ionic liquids are considered; some of these address the solubility of species in ionic liquids while others examine classes of reaction where the outcome in ionic liquids can be explained through the application of computational approaches. Overall, the utility of computational methods to explain, and potentially predict, the effect of ionic liquids on reaction outcome is demonstrated

Modulating the photoluminescence of europium-based emitting polymers: Influence of the matrix on the photophysical properties

A series of luminescent materials have been prepared by the ternary europium complex Eu(tta)3(phen) (tta = 2-thenoyltrifluoroacetonato, phen = 1,10-phenanotroline) embedded into different polymer matrixes (polystyrene, poly(vinyl difluoride), poly(acrylonitryle) and poly(methyl methacrylate)) in order to investigate the effect of the polymer on the luminescent properties of the hybrid materials. Fourier transform infrared spectra (FTIR), UV/vis spectra, scanning electron microstructure (SEM) and luminescent properties of the europium complex and the hybrid materials are described in detail. In all cases, interaction between the polymer and the europium complex was observed from the above techniques. This interaction was strong enough to lead to a variation in the photoluminescent properties of the hybrid films: while poly(vinyl difluoride) doped polymers showed a reduce quantum yield (φ = 24%), a dramatic/significant enhanced in this parameter (φ up to 73%) was observed for the other materials in comparison with the φ value of the precursor complex (30.5%). This result may support the conclusion that while some polymers could interact with the complex, act as antennae and transfer energy to the central Eu(III) ion, other quench the luminescence of the complex. Based on this high φ, these films could be applied in top optical applications such as light-emitting diodes and/or active polymer optical fibers. © 2013 Elsevier B.V

Highly efficient luminescent materials: Influence of the matrix on the photophysical properties of Eu(III) complex/polymer hybrids

Highly efficient luminescent materials based on the europium complex Eu(tta)3(phen) (tta = 2-thenoyltrifluoracetonato, Phen = 1,10-phenantroline) incorporated into different polymer matrixes (polyvinyl butyral, polysulfone and polyurethane) have been prepared. The photoluminescent hybrid films were prepared by solution mixing/drop casting which has been revealed as a very convenient method to prepare these polymeric materials because of the good homogeneous distribution of the Eu(III) complex into the polymer matrix. A detail analysis of the Fourier transform infrared spectra, UV/Vis spectra and photoluminescent properties is presented. These results agree with the conclusion that the polymer interact with the complex, act as antenna and transfer energy to the central Eu(III) ions. As a result of this interaction, the efficiencies of the doped films are dramatically enhanced (photoluminescence quantum yields in the range 58-86%) in comparison with that of the precursor complex. The luminescent Eu(tta)3(phen) complex-polymer hybrid materials developed in this study could be successfully applied in optical devices as polymer light-emitting diodes or active polymer optical fiber applications. © 2014 Elsevier B.V