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Namur, Belgium

The University of Namur or Université de Namur, in Namur , is a Jesuit, Catholic public university in the French Community of Belgium. Both teaching and research are carried out in six Faculties or university level schools in the fields of: Philosophy and Lettres Law Economic, Social, and Management science Computer science science Medicine↑ Wikipedia.

We have conducted a theoretical investigation to model the mechanisms of photoinduced electron injection and energy transfer for a recent organic metal-free dye derived from the triphenylamine (2TPA-R) structure. The 2TPA-R system results from the fusion between two TPA moieties connected by a vinyl group, and the rhodanine-3-acetic acid is used as the electron acceptor group. In a first step, DFT and TDDFT approaches have been exploited to calculate the key parameters controlling the intramolecular charge transfer (ICT) injection and ET transfer rate constants in the classical Marcus formalism: (i) the electronic coupling; (ii) the reorganization energies; and (iii) the variation of the Gibbs energy. In a nice agreement with the experimental trends, the results have highlighted that (i) two excited states [EE(1), lower in energy, and EE(2), higher in energy] have been calculated at 2.78 and 3.33 eV; (ii) the energy transfer (ET) between these two excited states is in competition with the electron injection from the EE(2); (iii) when 2TPA-R is excited at 3.33 eV, the ET between the resulting relaxed excited states EE(2) and EE(1) directly takes place, and the probability of injection from EE(2) is weak; (iv) the ET remains governed by the Dexter mechanism. Indeed, the ratio between the Förster and Dexter rate constants (kF/kD) is evaluated at ∼10-4. Second, we propose structural modifications improving the electron injection efficiency of the TPA-based DSSCs, and we show that using the 1-CN,2-COOH-ethylene group as the acceptor unit combined with a functionalization of the TPA moieties by -OMe groups significantly improves the key parameters related to the electron injection. © 2010 American Chemical Society. Source

Rinaldi M.,University of Namur
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

We study the gravitational field equations in the presence of a coupling between the derivative of a massless scalar field and the Einstein tensor. This configuration is motivated by Galileon gravity as it preserves shift invariance in the scalar sector. We analytically obtain solutions with static and spherically symmetric geometry, which also include black holes with a single regular horizon. We examine the thermodynamical properties of these solutions, and we reveal the nonperturbative nature of the coupling constant. We also find a phase transition, similar to the one described by Hawking and Page, which occurs at a critical temperature determined by both the black hole mass and by the strength of the coupling. © 2012 American Physical Society. Source

University of Namur | Date: 2013-04-25

Functional multilayer systems and are used in the manufacture of various devices such as detecting and sensor devices. More specifically, porous multilayer systems are capable of switching from a transparent state to a Bragg reflector state by introducing a suitable composition into the porous multilayer system, or via displacement of a suitable composition through the porous multilayer system.

A method for analyzing a sample with a light probe with a spatial resolution smaller than the wavelength of the light probe comprising the steps of: illuminating the sample by a first light pulse saturating a vibrational and/or electronic transition, said light pulse presenting an intensity spatial distribution on the sample presenting at least one minimum wherein saturation does not occur, measuring the local absorbance properties and/or the local second order non-linear susceptibility of the sample by using a second light pulse forming the light probe at a wavelength corresponding to said electronic and/or vibrational transition, wherein the second light pulse overlap said first light pulse intensity minimum.

Ucl Business Plc and University of Namur | Date: 2012-03-16

Borazine derivatives are used in the manufacture of electronic devices, in particular electroluminescent and semiconductor devices. More specifically, stable borazine derivatives include boron atoms substituted by aryl groups used in one or more layers of an electroluminescent or a semiconductor device, in particular in the emissive layer of organic light-emitting devices (OLED).

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