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A novel family of square-planar Pd(II) complexes based on isoquinoline-functionalised pyrazolate ligands [Pd(pzR(n,n)iq)2] (R(n,n) = C6H3(OCnH2n+1)2, n = 4, 6, 8, 10, 12, 14, 16, 18) has been synthesised and characterised. The new complexes show mesomorphic properties and exhibit columnar mesophases that are highly-stable in exceptionally wide temperature ranges of up to 345 °C. The formation of nanochannels in the fluid liquid crystal phases generates continuous pathways for one-dimensional proton conduction on the basis of C–H⋯N proton transfer. The complex with an intermediate chain length (n = 12) shows the highest proton conductivity of 1.34 × 10−4 S m−1 at 269 °C in the hexagonal columnar mesophase, and an activation energy of 0.84 eV. The influence of both the terminal alkyl chain length and the mesophase columnar organisation on the proton conduction mechanism is demonstrated. The series of Pd(II) complexes investigated in this work constitutes one of the first examples of proton-conducting metallomesogens with potential applications in PEM fuel cells., Ministerio de Economía y Competitividad, Programa de Financiación de Universidad Complutense de Madrid-Santander Universidades (Spain), Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Está depositada la versión postprint del artículo, Several series of dihalide Pd(ii) compounds bearing pyridyl or isoquinolinylpyrazole ligands have been strategically designed and synthesised to exhibit columnar mesomorphism in wide stability ranges. The coordination of the pyrazoles to the fragments PdX2 (X = Cl, Br, I) generates half-disc molecules that are capable of self-assembling into discotic dimers via intermolecular interactions. This disc-like shape is required for the supramolecular organisation of the lamellar columnar mesophases, which are formed at temperatures below 100 degrees C in most cases. It was found that these metallomesogens behave as 2D proton conducting materials under anhydrous conditions. The high fluidity properties of the mesophase facilitate proton conduction as a result of the spontaneous dissociation of the acidic pyrazole proton at the melting temperature. For the first time, lamellar columnar mesophases are demonstrated to serve as a 2D platform to induce water-free proton conductivity in dihalide Pd(ii) metallomesogens., Ministerio de Economía y Competitividad (España), Universidad Complutense de Madrid, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

The luminescence properties of Pt(II) compounds can be modulated by controlling the assembly of their molecules both in the solution and in the solid state. This fact constitutes a powerful tool for developing materials with stimuli-responsive luminescence properties. Herein, we describe the self-assembly behaviour of several series of Pt(II) metallomesogens in two different media upon controlled conditions. On the one hand, we explore the ability of several metal cations to induce the formation of Pt⋯Pt aggregates in solution, with the main goal of enhancing the phosphorescent emission of these compounds. On the other hand, since these compounds exhibit liquid crystalline mesophases and the temperature can control the aggregation, we have fabricated Pt(II) compound-doped polymer films and silicone membranes that show stimuli-responsive luminescent properties. In both cases, the interactions between the Pt(II) compounds and the metal cations, or the polymer matrices, play a key role in the aggregation-induced emission enhancement (AIEE) behaviour of the dyes. The effects of the alkyl chain length, the molecular asymmetry, and the nature of the ligands in the establishment of these interactions are also evaluated., Ministerio de Economía y Competitividad, MINECO/FEDER (Spain), project CTQ2015-63858-P, PROTEOMASS Scientific Society (Portugal), Associate Laboratory for Green Chemistry-LAQV/REQUIMTE, FCT/MEC (Portugal), project UID/QUI/50006/2013, Universidad Complutense de Madrid-Santander Universidades (Spain), Fundación Alfonso Martín Escudero (Spain), Ministerio de Economía y Competitividad (Spain) and European Social Fund - BES-2014-070964, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

The luminescence properties of Pt(II) compounds can be modulated by controlling the assembly of their molecules both in the solution and in the solid state. This fact constitutes a powerful tool for developing materials with stimuli-responsive luminescence properties. Herein, we describe the self-assembly behaviour of several series of Pt(II) metallomesogens in two different media upon controlled conditions. On the one hand, we explore the ability of several metal cations to induce the formation of Pt⋯Pt aggregates in solution, with the main goal of enhancing the phosphorescent emission of these compounds. On the other hand, since these compounds exhibit liquid crystalline mesophases and the temperature can control the aggregation, we have fabricated Pt(II) compound-doped polymer films and silicone membranes that show stimuli-responsive luminescent properties. In both cases, the interactions between the Pt(II) compounds and the metal cations, or the polymer matrices, play a key role in the aggregation-induced emission enhancement (AIEE) behaviour of the dyes. The effects of the alkyl chain length, the molecular asymmetry, and the nature of the ligands in the establishment of these interactions are also evaluated., Ministerio de Economía y Competitividad (España), PROTEOMASS Scientific Society (Portugal), Associate Laboratory for Green Chemistry (Portugal), Universidad Complutense de Madrid, Fundación Alfonso Martín Escudero (Spain), European Commission, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

©2019 Royal Society of Chemistry The authors thank the Spanish Ministerio de Economia y Competitividad (project CTQ2015-63858-P (MINECO/FEDER)) for funding. C. Cuerva acknowledges the Universidad Complutense de Madrid for his predoctoral contract (Programa de Financiacion de Universidad Complutense de Madrid-Santander Universidades)., Several series of dihalide Pd(II) compounds bearing pyridyl or isoquinolinylpyrazole ligands have been strategically designed and synthesised to exhibit columnar mesomorphism in wide stability ranges. The coordination of the pyrazoles to the fragments PdX_2 (X = Cl, Br, I) generates half-disc molecules that are capable of self-assembling into discotic dimers via intermolecular interactions. This disc-like shape is required for the supramolecular organisation of the lamellar columnar mesophases, which are formed at temperatures below 100 ºC in most cases. It was found that these metallomesogens behave as 2D proton conducting materials under anhydrous conditions. The high fluidity properties of the mesophase facilitate proton conduction as a result of the spontaneous dissociation of the acidic pyrazole proton at the melting temperature. For the first time, lamellar columnar mesophases are demonstrated to serve as a 2D platform to induce water-free proton conductivity in dihalide Pd(ii) metallomesogens., Ministerio de Economía y Competitividad (MINECO)/FEDER, Universidad Complutense de Madrid/Banco de Santander, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

Metallomesogens (liquid crystals containing metals) offer a great opportunity to designadvanced materials. The possibility of combining the supramolecular ordering of liquidcrystals with the typical properties derived from the metal centre (photoluminescence,electroluminescence, magnetism, etc.) gives access to a wide spectrum of potentialapplications in fields such as optoelectronics, energy or medicine. The design of novelspecies that exhibit high thermal stability and improved properties constitutes one of thegreatest challenges when obtaining these multifunctional materials.The main objective of this research project is driven to obtain highly-stable liquidcrystallinematerials based on discotic metallomesogens that additionally exhibit otherproperties such as photoluminescence, electroluminescence or conductivity. The presentwork aims to demonstrate that metallomesogens can be promising candidates for the nextgeneration of new technologies..., Los metalomesógenos (cristales líquidos conteniendo metales) constituyen una excelenteoportunidad para diseñar nuevos materiales avanzados. La posibilidad de combinar elordenamiento supramolecular de los cristales líquidos con las propiedades derivadas delcentro metálico (fotoluminiscencia, electroluminiscencia, magnetismo, etc.) abre un amplioabanico de interesantes aplicaciones en campos como el de la energía, la optoelectrónica ola medicina. Hoy en día, el diseño de nuevas especies que tengan una alta estabilidadtérmica y propiedades mejoradas supone uno de los mayores retos a la hora de prepararestos materiales.El objetivo principal desarrollado en esta tesis doctoral se ha dirigido a la obtención demateriales constituidos por metalomesógenos discóticos que exhiban comportamientocristal líquido y que, además, muestren propiedades adicionales como fotoluminiscencia,electroluminiscencia o conductividad. Este proyecto pretende demostrar que losmetalomesógenos pueden ser candidatos idóneos para la próxima generación de nuevas tecnologías...

© 2018 by the authors Mercedes Cano thanks the Spanish Ministerio de Economía y Competitividad (CTQ2015-63858- ) for funding. María Jesús Pastor acknowledges the Ministerio de Economía y Competitividad for her FPI scholarship. Ignacio Sánchez acknowledges the Ministerio de Educación, Cultura y Deporte for his FPU scholarship. Rainer Schmidt wishes to express his gratitude to Alberto Rivera-Calzada, Carlos León and Jacobo Santamaría for allowing the use and assistance with the dielectric spectroscopy facilities, Ionic liquid crystals (ILCs) are a class of materials that combine the properties of liquid crystals (LCs) and ionic liquids (ILs). This type of materials is directed towards properties such as conductivity in ordered systems at different temperatures. In this work, we synthesize five new families of ILCs containing symmetrical and unsymmetrical substituted pyrazolium cations, with different alkyl long-chains, and anions such as Cl‾, BF₄‾, ReO₄‾, p-CH₃₋₆H₄SO₃‾(PTS) and CF₃SO₃‾ (OTf). We study their thermal behavior by polarized light optical microscopy (POM) and differential scanning calorimetry (DSC). All of them, except those with OTf as counteranion, show thermotropic mesomorphism. The observations by POM reveal textures of lamellar mesophases. Those agree with the arrangement observed in the X-ray crystal structure of [H₂pzᴿ⁽⁴⁾‚ᴿ⁽⁴⁾][ReO₄]. The nature of the mesophases is also confirmed by variable temperature powder X-ray diffraction. On the other hand, the study of the dielectric properties at variable temperature in mesomorphic (Cl‾‾and BF₄‾) and non-mesomorphic OTf) salts indicates that the supramolecular arrangement of the mesophase favors a greater ionic mobility and therefore ionic conductivity., Ministerio de Economía y Competitividad (MINECO), Ministerio de Educacion, Cultura y Deporte, Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

La evaluación es un proceso fundamental dentro del sistema de enseñanza-aprendizaje, cuyo desarrollo realizan los profesores. Se propone en este proyecto que los estudiantes sean también constituyentes activos en el sistema de evaluación.

A novel family of square-planar Pd(II) complexes based on isoquinoline-functionalised pyrazolate ligands [Pd(pzR(n,n)iq)2] (R(n,n) = C6H3(OCnH2n+1)2, n = 4, 6, 8, 10, 12, 14, 16, 18) has been synthesised and characterised. The new complexes show mesomorphic properties and exhibit columnar mesophases that are highly-stable in exceptionally wide temperature ranges of up to 345 °C. The formation of nanochannels in the fluid liquid crystal phases generates continuous pathways for one-dimensional proton conduction on the basis of C–H⋯N proton transfer. The complex with an intermediate chain length (n = 12) shows the highest proton conductivity of 1.34 × 10−4 S m−1 at 269 °C in the hexagonal columnar mesophase, and an activation energy of 0.84 eV. The influence of both the terminal alkyl chain length and the mesophase columnar organisation on the proton conduction mechanism is demonstrated. The series of Pd(II) complexes investigated in this work constitutes one of the first examples of proton-conducting metallomesogens with potential applications in PEM fuel cells., Ministerio de Economía y Competitividad (España), Universidad Complutense de Madrid, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Hay actualmente un gran interés en la consecución de materiales moleculares, con funcionalidades añadidas para su aplicación en tecnologías emergentes. En particular, los materiales líquido-cristalinos son de gran importancia debido a que están presentes en multitud de campos de la vida cotidiana, tecnológicos como pantallas de televisión, ordenadores, calculadoras y relojes, o en otros tan dispares como detergentes, cosméticos o termómetros de temperatura. En este contexto de aplicabilidad, los cristales líquidos luminiscentes, que combinan propiedades mesomórficas y fotofísicas, resultan muy atractivos, ya que pueden utilizarse para aplicaciones optoelectrónicas, por ejemplo, como fuente de luz en dispositivos cristal líquido (LCDs) y en sistemas de imágenes tridimensionales, entre otras. Por otra parte, los cristales líquidos iónicos son también interesantes debido a su sencilla estructura, compuestos de cationes y aniones, y a la combinación de las propiedades mesogénicas, de los cristales líquidos, e iónicas, de los líquidos iónicos, lo que les confiere características útiles para distintas aplicaciones en electrónica molecular, baterías, células solares o como disolventes en reacciones químicas, materiales electrocrómicos, etc. El diseño de nuevas especies con propiedades optimizadas cristal líquido y que presenten otras adicionales como luminiscencia, conductividad, etc., constituye uno de los retos actuales de investigación. Bajo estas premisas, el objetivo principal desarrollado en este trabajo de investigación se ha dirigido a la obtención de nuevos materiales moleculares con propiedades cristal líquido que combinaran funcionalidades adicionales, como son los metalomesógenos luminiscentes o los cristales líquidos iónicos, basados en compuestos de coordinación o especies híbridas orgánicas/inorgánicas, respectivamente. En el primer caso, se trata de determinar la influencia de diferentes factores que contribuyan a un diseño molecular adecuado para obtener a

Metallomesogens (liquid crystals containing metals) offer a great opportunity to designadvanced materials. The possibility of combining the supramolecular ordering of liquidcrystals with the typical properties derived from the metal centre (photoluminescence,electroluminescence, magnetism, etc.) gives access to a wide spectrum of potentialapplications in fields such as optoelectronics, energy or medicine. The design of novelspecies that exhibit high thermal stability and improved properties constitutes one of thegreatest challenges when obtaining these multifunctional materials.The main objective of this research project is driven to obtain highly-stable liquidcrystallinematerials based on discotic metallomesogens that additionally exhibit otherproperties such as photoluminescence, electroluminescence or conductivity. The presentwork aims to demonstrate that metallomesogens can be promising candidates for the nextgeneration of new technologies...

Ministerio de Economía y Competitividad, (España), Universidad Complutense de Madrid, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

New dicatenar isoquinoline-functionalized pyrazoles, [HpzR(n,n)iq] (R(n,n)=C6H3(OCnH2n+1)2; n=4, 6, 8, 10, 12, 14, 16, 18), have been strategically designed and synthesized to induce mesomorphic and luminescence properties into the corresponding bis(isoquinolinylpyrazolate)platinum(II) complexes [Pt(pzR(n,n)iq)2]. Thermal studies reveal that all platinum(II) compounds exhibit columnar mesophases over an exceptionally wide temperature range, above 300 °C in most cases. The photophysical behavior was also investigated in solution and in the solid state. As a consequence of the formation of Pt⋅⋅⋅Pt interactions, the weak greenish emission of the platinum derivatives turns bright orange in the mesophase. Additionally, the complexes are sensitive to a great variety of external inputs, such as temperature, mechanical grinding, pressure, solvents, and vapors. On this basis, they are used as dopant agents of a polyvinylpyrrolidone or poly(methyl methacrylate) polymer matrix to achieve stimuli-responsive thin films., Ministerio de Economía y Competitividad (España), Universidad Complutense de Madrid, European Commission, Portuguese Foundation for Science and Technology, Scientific Society PROTEOMASS (Portugal), Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

© 2016 by the authors, licensee MDPI, Basel, Switzerland. Mercedes Cano thanks the Spanish Ministerio de Economía y Competitividad (project CTQ2011-25172 and CTQ2015-63858) and Complutense University (GR3/14-910300), for funding. María Jesús Pastor acknowledges the Ministerio de Economía y Competitividad for her FPI scholarship. Cristián Cuerva is grateful to the Programa de Financiación de Universidad Complutense de Madrid-Santander Universidades (Spain), for his predoctoral contract. María Jesús Pastor, Cristián Cuerva, José A. Campo and Mercedes Cano thank to Dra. Paloma Ovejero for her help with the synthesis and characterization of the compounds. Rainer Schmidt wishes to express his gratitude to Alberto Rivera-Calzada, Carlos León and Jacobo Santamaría for allowing the use and assistance with the dielectric spectroscopy., Ionic liquid crystals (ILCs) allow the combination of the high ionic conductivity of ionic liquids (ILs) with the supramolecular organization of liquid crystals (LCs). ILCs salts were obtained by the assembly of long-chained diketonylpyridinium cations of the type [HOO^(R(n)pyH)] + and BF_(4)^(-) , ReO_(4)^(-), NO_(3)^(-), CF_(3)SO_(3)^(-), CuCl_(4)^(2-) counter-ions. We have studied the thermal behavior of five series of compounds by differential scanning calorimetry (DSC) and hot stage polarized light optical microscopy (POM). All materials show thermotropic mesomorphism as well as crystalline polymorphism. X-ray diffraction of the [HOO^(R(12)pyH)][ReO_(4)] crystal reveals a layered structure with alternating polar and apolar sublayers. The mesophases also exhibit a lamellar arrangement detected by variable temperature powder X-ray diffraction. The CuCl_(4)^(2-) salts exhibit the best LC properties followed by the ReO_(4)^(-) ones due to low melting temperature and wide range of existence. The conductivity was probed for the mesophases in one species each from the ReO_(4)^(-) , and CuCl_(4)^(2-) families, and for the solid phase in one of the non-mesomorphic Cl^(-) salts. The highest ionic conductivity was found for the smectic mesophase of the ReO_(4)^(-) containing salt, whereas the solid phases of all salts were dominated by electronic contributions. The ionic conductivity may be favored by the mesophase lamellar structure., Ministerio de Economía y Competitividad (MINECO), Universidad Complutense de Madrid, Programa de Financiación de Universidad Complutense de Madrid-Santander Universidades (Spain), Depto. de Estructura de la Materia, Física Térmica y Electrónica, Fac. de Ciencias Físicas, TRUE, pub