Charge transport and structural dynamics in low molecular weight and polymerized 1-vinyl-3-pentylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquids (ILs) are investigated by a combination of broadband dielectric spectroscopy, dynamic mechanical spectroscopy and differential scanning calorimetry. While the dc conductivity and fluidity exhibit practically identical temperature dependence for the non-polymerized IL, a significant decoupling of ionic conduction from structural dynamics is observed for the polymerized IL. In addition, the dc conductivity of the polymerized IL exceeds that of its molecular counterpart by four orders of magnitude at their respective calorimetric glass transition temperatures. This is attributed to the unusually high mobility of the anions especially at lower temperatures when the structural dynamics is significantly slowed down. A simple physical explanation of the possible origin of the remarkable decoupling of ionic conductivity from structural dynamics is proposed.

NIR-sensitized photoinduced atom-transfer radical polymerization (ATRP) is possible by using ppm of Cu II /tris(2pyridylmethyl)amine (TPMA) as the catalyst, apolymethine as the photosensitizer,a nd a-bromophenylacetate as the alkyl halide initiator.A mong the polymethines investigated with cationic, zwitterionic,o ra nionic structures,o nly the zwitterionic 2 exhibited sensitization activity under NIR light at room temperature resulting in the formation of polymers with controlled molecular weight characteristics and functionalities. The barbital group placed at the meso-position of 2 caused the activity in this photo-ATRP framework. The chain-end fidelity of the polymers was confirmed by chain extension and block copolymerization experiments.T he polymerization system exhibits high photostability under NIR light exposure and irradiation dependency as demonstrated by light on/off experiments.

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Diffusion in a series of ionic liquids is investigated by a combination of Broadband Dielectric Spectroscopy (BDS) and Pulsed Field Gradient Nuclear Magnetic Resonance (PFG NMR). It is demonstrated that the mean jump lengths increase with the molecular volumes determined from quantum-chemical calculations. This provides a direct means-via Einstein-Smoluchowski relation-to determine the diffusion coefficient by BDS over more than 8 decades unambiguously and in quantitative agreement with PFG NMR measurements. New possibilities in the study of charge transport and dynamic glass transition in ionic liquids are thus opened.Ionic liquids are under investigation for use as reaction media, in batteries and supercapacitors, solar and fuel cells, electrochemical deposition of metals and semiconductors, protein extraction and crystallization, nanotechnology applications, physical chemistry, and many others.1-3 However, the interplay between the molecular structure and diffusivity in these materials remains unclear despite the fact that diffusion is one of the key processes determining the performance and technological applications involving ILs. In the current study, experimental and theoretical approaches are combined to investigate the quantitative relationship between the structure and dynamics in a series of ionic liquids. For the first time, we demonstrate that the mean ion jump length-a key quantity determining the ion mobility-increases with molecular volume of the ionic liquids investigated.Diffusion is a ubiquitous and fundamental process characterized by the haphazard motion of elementary constituents of matter, most notably of atoms and molecules, due to their thermal energy. It maintains the functionality of living cells, determines the rates of chemical reactions, facilitates electrical conduction, and forms the basis of numerous technological applications.4-6 Fick's first law of diffusion provides a means of explaining the process in terms of mass transport down a concentration gradient. Within this framework, the diffusive flux, j, is given by j ¼ ÀD(c)Vc where c denotes the concentration, D is the diffusion coefficient of the diffusants, and V is a vector del operator. The concentration profile due to diffusion at time t can be determined upon consideration of the principle of mass conservation. This yields Fick's second law of diffusion expressed as vc/vt ¼ V(D(c)Vc). This approach, although widely used, does not provide a direct link to the molecular structure of the material under consideration.Einstein and Smoluchowski proposed a microscopic description of diffusion. According to this view, the particles (diffusants) haphazardly hop, executing random walk quantifiable through the Einstein-Smoluchowski relation (written as hr 2 i ¼ 6Dt, where hr 2 i represents the mean-square distance traversed by the diffusants in time t). The random motion of individual particles gives rise to a diffusive flux on a macroscopic level that can be described by Fick's laws of diffusion. It can be easily shown that the mea...