Evaluating the Role of Intermolecular Interactions in pi-conjugated Materials: What can we learn from DFT calculations and Raman Spectroscopy

For practical applications in sensors, dynamic covalent chemistry and molecular (photochromic) switches, soft conjugated materials can be envisaged as promising functional materials.1 To advance in this research field, deciphering the mechanisms involved on how sensitive the structural and electronic properties are to specific molecular ordering is essential. In stimuli responsive materials, such as piezochromic materials, the molecular orientation and intermolecular interactions can change upon mechanical grinding. In this context, Raman spectroscopy can help to clarify how organic molecular solids respond to high pressure, for instance, by reducing intermolecular interactions and/or changing molecular conformations. On the other hand, DFT calculations can help us to rationalize the nature and stability of the formation of aggregates and complexes, allowing the evaluation of the effects of the surrounding media on different molecular properties.3 Thus, we propose here a combined Raman spectroscopy and DFT study of molecular crystals and/or aggregates upon soft external stimuli that can be envisaged as a very sensitive approach to understand the structural effects causing any chromic changes. To this end, we focus on different families of conjugated materials with potential application in organic electronics, ranging from cyclophane aggregates to tetrathiazolylthiophenes crystals (Figure 1).Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Impact of the Intermolecular Interactions on the Electronic and Charge-Transport Properties of Organic Materials: A Joint Experimental and Theoretical Approach

The use of organic materials to design electronic devices has actually presented a broad interest because they constitute an ecological and suitable resource for our current "electronic world". These materials provide several advantages (low cost, light weight, good flexibility and solubility to be easily printed) that cannot be afforded with silicon.[1] They can also potentially interact with biological systems, something impossible with inorganic devices. The performance of the organic-based electronic devices critically depends not only to the intrinsic properties of the conjugated cores but also to the supramolecular arrangement.[2] In this contribution, we present some of our more recent investigations on this field dealing with the better understanding of the complex structure-properties relationships of organic nanomaterials.[3] For this purpose, we use a joint experimental and theoretical approach that includes spectroscopic measurements and molecular modeling.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Multiresponsive chromic soft materials: formation of macrocycles from carbazole-based biradicaloids

-conjugated biradical compounds become essential building blocks in DCC (dynamic covalent chemistry).1 This field is based on the creation of structural scaffolds based on chemical components which interact through strong but reversible bonds. Importantly, dynamic covalent bonds will be at the center of attention because of their unique feature to become reversible under mild conditions.2 Recently, we have demonstrated the reversible interconversion between a stable quinoid precursor based on a para-substituted carbazole with terminal dicyanomethylene groups and a macrocycle cyclophane upon soft external stimuli (temperature, pressure, light), which results on strong chromic features.3 In this work, we investigate the interconversion of the monomer/cyclophane transformation in carbazole-based systems, both in solution and solid state, upon external stimuli. To this end, we use a combined experimental and theoretical study that links vibrational spectroscopy (Raman and IR) with DFT calculations.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Carbazole-based biradicaloids as potential building blocks for dynamic covalent chemistry

Pi-conjugated biradical compounds become essential building blocks in DCC (dynamic covalent chemistry).1 This field is based on the creation of structural scaffolds based on chemical components which interact through strong but reversible bonds. Importantly, dynamic covalent bonds will be at the center of attention because of their unique feature to become reversible under mild conditions.2 Recently, we have demonstrated the reversible interconversion between a stable quinoid precursor based on a para-substituted carbazole with terminal dicyanomethylene groups and a macrocycle cyclophane upon soft external stimuli (temperature, pressure, light), which results on strong chromic features.3 In this work, we investigate the impact of the substitution pattern (i.e., the insertion of dicyanomethylene groups at the 2,7 (para) or 3,6 (meta) positions or the elongation of the carbazole backbone) on the formation of stimuli-responsive cyclophanes by self-assembly. To this end, we use a combined experimental and theoretical study that links vibrational spectroscopy (Raman and IR) with DFT calculations.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec

Aprendizaje-Servicios (ApS). Una nueva metodología para trabajar las competencias básicas de forma participativa y colaborativa

Depto. de Estudios EducativosFac. de EducaciónFALSEsubmitte

Morir de golpe

En este trabajo analizo el sistema de represión de la dictadura franquistay sus resultados, identificando los mecanismos de penetración, perpetuación y naturalizaciónde su dominación e ideología a través de la familia de un represaliadopor el régimen, descifrando las causas y los efectos del silencio intergeneracional, losproblemas de comunicación y (falta de) transmisión de la memoria del represaliadoy de la violencia del sistema dictatorial, como también los miedos, las tensiones ylos conflictos que se generaron ante la ruptura del silenciamiento por parte de unode los nietos cuando se dispuso a averiguar sobre la vida y el destino de su abuelo.También analizo y describo las representaciones de cada uno de sus integrantes ysus transformaciones a medida que la búsqueda avanzaba y con ella aumentaba elconocimiento de la violencia represiva del régimen franquista

Argentina case study

The aim of the project is to analyze and understand the events that have taken place throughout history in Argentina, which have made a country that had incredible potential suffer devastating economic and political situations, ending in one of the most serious defaults in history. Additionally, the project summarizes in a SWOT Analysis (Strengths, Weaknesses, Opportunities and Threats) the situation that Argentina is currently living, under the new government that started in 2015 with President Mauricio Macri. Thanks to recently instituted policies, Argentina has been able to introduce itself again in the international trading market and is now one of the emerging economies with a brighter future

Data hidding in color images using perceptual models

One of the problems arising from the use of digital media is the ease of identical copies of digital images or audio files, allowing manipulation and unauthorized use. Copyright is an effective tool for preserving intellectual property of those documents but authors and publishers need effective techniques that prevent from copyright modification, due to the straightforward access to multimedia applications and the wider use of digital publications through the www. These techniques are generally called watermarking and allow the introduction of side information (i.e. author identification, copyrights, dates, etc.). This work concentrates on the problem embedding and optimum blind detection of data in color images through the use of spread spectrum techniques, both in space (Direct Sequence Spread Spectrum or DSSS) and frequency (Frequency Hopping). It is applied to RGB and opponent color component representations. Perceptive information is considered in both color systems. Some tests are performed in order to ensure imperceptibility and to assess detection quality of the optimum color detectors.Peer ReviewedPostprint (published version

Sgames Active Classroon: Proyecto de Innovación para el aumento de la práctica de actividad física en Educación Secundaria Obligatoria

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