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Deposition of the top-contact electrode to create large-area electrode | monolayer | electrode junctions represents a contemporary challenge to the integration of molecular electronic phenomena into device structures. Here, a top contact electrode is formed on top of an organic monolayer over a large area (cm2) by two simple, sequential self-assembly steps. Initial self-assembly of 4,4′-(1,4-phenylenebis(ethyne-2,1-diyl))dianiline onto gold-on-glass substrates gives high-quality monolayers. The exposed amine functionality is subsequently used to anchor uncapped gold nanoparticles deposited in a second self-assembly step. These uncapped gold nanoparticles are prepared by thermolysis of lipoic acid stabilized gold nanoclusters and contain gold oxide (≈9%) that provides stability in the absence of an organic capping ligand. This two-step procedure results in full coverage of the monolayer by the densely packed gold nanoparticles, which spontaneously condense to give a semi-continuous film. The electrical properties of these junctions are determined from I–V curves, revealing uniform electrical response and absence of metallic short-circuits or evidence of damage to the underlying molecular monolayer. These promising electrical characteristics suggest that the deposition of uncapped gold nanoparticles on suitably functionalized molecular monolayers provides a path for the fabrication of molecular electronic devices using simple methodologies., P.C., J.L.S., S. Martín, and J.G. are grateful for financial assistance from Ministerio de Ciencia e Innovación from Spain and fondos FEDER in the framework of projects PID2019-105881RB-I00, PID2019-105408GB-I00, and PGC2018-097583-B-I00. J.L.S. also acknowledges the funded project Hierarchical Self Assembly of Polymeric Soft Systems, “SASSYPOL,” from the 7th Framework Programme (CEE, Ref-607602). L.H., S. Martín, J.L.S, P.C., S. de Marcos, and J.G. acknowledge support from DGA/Fondos FEDER (construyendo Europa desde Aragón) for funding PLATON (E31_20R), CLIP (E47_17R) and N&SB (E25_17R) research groups. P.J.L. gratefully acknowledges support from the Australian Research Council (DP190100073; DP190100074). R.S. is grateful for the support provided by PASPA of the DGAPA and Engineering Faculty of National Autonomous University of Mexico.

The synthesis and liquid crystalline behavior of new calixarene Schiff base derivatives are reported. The materials were obtained by reaction of a tetraaminocalix[4]arene derivative with three aldehydes as mesogenic promotor moieties: 4‐(4′‐decyloxybenzoyloxy)benzaldehyde (A), 4‐(4′‐decyloxybenzoyloxy)salicylaldehyde (B) and 4‐(3′,4′‐didecyloxybenzoyloxy)salicylaldehyde (C). All of the compounds exhibit liquid crystalline properties and these were studied by optical microscopy, DSC and X‐ray diffraction. The relationship between the structure and the mesomorphic behavior of the compounds is discussed. The binding recognition and selectivity towards cations have been studied by absorption and fluorescence spectroscopy., This work was supported by MINECO Spain, under the Projects CTQ2015‐70174P and CTQ2014‐52331R, FEDER funding and Gobierno de Aragón‐FSE (Research Group E04 and E39). A. Concellón thanks MINECO (Spain) for his PhD grant.

Novel liquid crystal (LC) dendrimers have been synthesised by hydrogen bonding between an s-triazine as the central core and three peripheral dendrons derived from bis(hydroxymethyl)propionic acid. Symmetric acid dendrons bearing achiral promesogenic units have been synthesised to obtain 3:1 complexes with triazine that exhibit LC properties. Asymmetric dendrons that combine the achiral promesogenic unit and an active moiety derived from coumarin or pyrene structures have been synthesised in order to obtain dendrimers with photophysical and electrochemical properties. The formation of the complexes was confirmed by IR and NMR spectroscopy data. The liquid crystalline properties were investigated by differential scanning calorimetry, polarising optical microscopy and X-ray diffractometry. All complexes displayed mesogenic properties, which were smectic in the case of symmetric dendrons and their complexes and nematic in the case of asymmetric dendrons and their dendrimers. A supramolecular model for the lamellar mesophase, based mainly on X-ray diffraction studies, is proposed. The electrochemical behaviour of dendritic complexes was investigated by cyclic voltammetry. The UV/Vis absorption and emission properties of the compounds and the photoconductive properties of the dendrons and dendrimers were also investigated. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., This work was supported by the seventh FP THE PEOPLE PROGRAMME, The Marie Curie Actions, ITN, no. 215884-2, the MINECO, Spain, (under Projects: CTQ2012-35692 and MAT2012-38538-CO3-01), which included FEDER funding, and the Aragón Government-FSE (Project E04). A.G. and R.T. acknowledge support from the European Community’s Seventh Framework Program (FP7 2007–2013) through the MATERIA Project (PONa3_00370) and from MIUR through the PRIN 2012JHFYMC project. M.B. acknowledges support from the EU through an ESR fellowship.

Cyclic trinuclear gold(I) complexes with chiral 3,5-diarylpyrazolate ligands have been synthesized and characterized with the aim of obtaining helical columnar liquid-crystal phases as a way to control the stacking geometry and orientation of the trigold metallacycle in the bulk phase. The compounds bear n-decyloxy- and/or (S)-3,7-dimethyloctyloxy terminal groups in a number varying from twelve to eighteen. The compounds behave like isotropic glasses, crystalline solids, or columnar liquid crystals (of hexagonal or rectangular symmetry), with isotropization temperatures close to room temperature. In the case of the compound bearing nine n-decyloxy- and nine (S)-3,7-dimethyloctyloxy terminal groups, a helical columnar phase is obtained that exhibits a well-formed hexagonal bidimensional lattice made of columns that consist of molecules stacked at regular distances and mutually rotated by 40° in a helical mode. Thin films display emission bands at room temperature in the blue region of the visible spectra, regardless of the phase or the molecular structure., The authors thank the Gobierno de Aragón and European Union, Fondo Social Europeo (FSE) (project PI109/09, research group E04), and the Spanish Ministerio de Economia y Competitividad (MINECO) and European Union (EU), Fondo Europeo para el Desarrollo Regional (FEDER) (project numbers CTQ2012-35692, CTQ2011-22516, and MAT2012-38538-CO3-01) for financial support.

A series of new liquid-crystalline dendrimers is synthesized from hexa(4-hydroxyphenyloxy)cyclotriphosphazene as the central core and bis(MPA) as a branching agent. The dendrimers are functionalized with azobenzene mesogenic moieties. The monodisperse nature of the dendrimers is confirmed by 1H and 31P{1H} NMR and by matrix assisted laser desorption/ionization (MALDI) mass spectrometry (MS). A study of the thermal properties reveals mesomorphic behavior. All of the materials exhibit a lamellar phase and this is confirmed to be smectic A in nature by X-ray diffraction. A nematic phase is also observed for the dendrimers that contain 4-cyanoazobenzene. A calamitic arrangement in which the mesogenic moieties point both upwards and downwards with respect to the cyclotriphosphazene core is proposed to explain the mesomorphic properties. The introduction of photochromic moieties leads to a photoresponse for these materials. The response to linearly polarized light is studied and an order parameter of about 0.5 is measured for dendrimer G1-Azo-3., This work was supported by the MINECO, Spain, under the projects MAT2011-27978-C02 (01 and 02), CTQ 2012-35692 and CTQ2011-22589, FEDER funding, Fondo Social Europeo, and Gobierno de Aragón (Dpto. de Ciencia, Tecnología y Universidad).

A polymer network is prepared by the thiol-yne photopolymerization of multifunctional dendrimer with a tetrathiol crosslinker. The network obtained shows a liquid crystalline phase at room temperature, which has been characterized by optical microscopy, differential scanning calorimetry, and X-ray diffraction. Photoinduced deformation of uniaxially aligned free-standing films of the photocrosslinked material has been demonstrated. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., Financial support from the MICIIN-FEDER project CTQ2009-09030, MAT2011-27978-C02-02 and Diputación General de Aragón-Fondo Social Europeo (DGA-FSE) is gratefully acknowledged. R.C.-P. acknowledges a fellowship from the Ministerio de Educación y Ciencia.

The synthesis and characterization of ionic liquid crystalline dendritic polymers based on the ammonium salts of commercially available poly(propylene imine) (PPI), poly(amidoamine) (PAMAM), poly(ethyleneimine) (PEI), and the fully methylated PEI (PEIMe) with 5-(4-cyanobiphenoxy)pentanoic acid (CBPA) are reported. The occurrence of proton transfer from the carboxylic acid to the amine groups is confirmed using IR and NMR techniques. The mesomorphic behavior is investigated by means of differential scanning calorimetry, polarizing optical microscopy, and X-ray diffractometry. Although CBPA exhibits monotropic nematic mesomorphism, all ionic complexes display enantiotropic liquid crystal properties. The relationship between the mesomorphism of the complexes and their structure is discussed. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., This work was supported by the MICINN, Spain, under Project CTQ2009-09030, and FEDER funding EU and by the Gobierno de Aragón (Project PI109/09, Research Group E04). S.H.-A. thanks the MICINN (Spain) for a FPU grant.

What a core-ker! By the appropriate combination of promesogenic bent-core structures and the C60 unit, lamellar polar liquid-crystal phases were induced (see scheme). The supramolecular organization of the functional fullerene-based assemblies, the temperature range of the soft phase, the stabilization of the mesophase-like order at room temperature, and the molecular switching under an electric field can be tuned, depending on the molecular structure., This research is supported by the MICINN-FEDER of Spain-UE MAT2009-14636-CO3, CT2008-00795, CSD2007-00010, the Aragón (E04), Basque (GI/IT-449-10), and Madrid (S2009/PPQ-1533) governments. We are also grateful to BSCH-UZ and the Aragon government (J.V.) and Basque Country (N.S.) for fellowship grants and Dr. B. Villacampa from ICMA for the SHG measurements.

The stacking order and distance in columnar phases of triindole-based liquid crystals is controlled by an ethynyl linker (see picture; orange rod) between the central triindole core (green) and the peripheral flexible chains of a discotic mesogen. Hole (h) mobility is very high even if the stacking distances is not very short and the conjugated system is not particularly extended., This work has been supported by CTQ2007-65683/BQU, (CTQ2009- 09030), S2009/MAT-1756/CAM, MiUR through the PRIN 2007 (2007WJMF2W) project, Gobierno de Aragón, 200960I086 PIE.

Making a stack: Helical columnar architectures are prepared by a hierarchical self-assembly process involving H-bonding, π–π, and ion–dipole interactions (see picture). The strategic combination of these supramolecular interactions within mesomorphic systems yields materials in which photoinduced chirality and the incorporation of ions can be used to design multifunctional liquid crystals., This work was supported by the CICYT projects MAT2009-14636-C03-01 and CTQ2009-09030, FEDER funding (EU), and the Aragon Government. F.V. thanks the MEC of Spain for a grant.

A molecular tug of war between non- and semifluorinated alkyl chains (see picture) occurs when they are forced together by ionic attachment to a poly(propylene imine) dendrimer. Unexpected mesomorphic properties appear as a consequence of the competition of both substituents to control the supramolecular organization of the molecules., This work was supported by CICYT-FEDER Spanish project CTQ2006-15611-CO2-01, UE project (7th FP—THE PEOPLE PROGRAMME. The Marie Curie Actions—ITN, No. 215884-2), and by the Gobierno de Aragón. S.H.-A. thanks the MICINN (Spain) for a grant.

The synthesis and characterization of a series of nematic SWNT-polyazomethine composites are described. The composites were prepared by in situ polymerization in the presence of 1 wt % of chemically modified SWNTs in such a way that they were either dispersed or covalently bonded to the polymeric matrix. The presence of the SWNTs did not alter the thermal behavior of the polymer matrix and, therefore, highly oriented fibers could be melt-extruded from the composites at moderate temperatures, as revealed by structural and morphological studies. Preliminary tests on tensile properties indicate that strength and stiffness were improved when compared with fibers without CNTs, particularly when SWNTs were covalently bonded to the polymeric matrix., This work was supported by the Government of Aragón projects PM046, T66, and E046; and CICYT-FEDER Spanish project MAT2005-06, 373-C02 and PETRI95-0771OP.

7 pages, 8 figures, 1 table.-- et al., A liquid crystalline homopolymer that has photoisomerizable methoxyazobenzene groups in the side chain has been synthesized and characterized. Thin films of the nematic glassy phase of this polymer have been processed in order to study the absorption spectra and the vibrational and electronic circular dichroism responses by irradiation with 488 nm circularly polarized light (CPL). Selective reflection of visible light demonstrates that the irradiation of this glassy nematic azopolymer induces a helix as a consequence of the chiral arrangement of the azobenzene units. Moreover, a wedge cell with an aligning layer for planar orientation was filled with the polymer with the aim of investigating the change in the macroscopic optical properties and optical textures of the azopolymer on irradiation with CPL. The transfer of chirality from CPL to azopolymer through chiral conformations is proposed as a model for explaining the supramolecular chirality.

4 pages, 3 figures, 2 tables., Octopolar tris[(phenyl)ethynyl]benzenes with high second-order nonlinear optical (NLO) activity form discotic liquid-crystalline mesophases whose properties depend on the length of the alkoxy chains. The molecules self-organize in a non-centrosymmetric fashion in the bulk phase which enables the construction of a simple, efficient, NLO device (see picture).

The phosphorylation of rat brain microtubule protein on intracranial injection of labeled phosphate has been analyzed. The major microtubule protein components phosphorylated in vivo in rat brain are the high-molecular-weight microtubule-associated proteins (MAPs) MAP-1A, MAP-1B, and MAP-2. A slight phospholabeling of β-tubulin, which corresponds to the phosphorylation of a minor neuronal β-tubulin isotype, is also observed. Whereas MAP-1B, MAP-2, and β-tubulin are phosphorylated in the brain of 5-day-old rat pups, when most neurons of the CNS are extending processes, MAP-1A phosphorylation is observed only after neuronal maturation takes place. The phosphorylation of MAP-1A, MAP-1B, and β-tubulin may be due mainly to casein kinase II or a related enzyme, whereas MAP-2 appears to be modified by other enzymes such as the cyclic AMP-dependent protein kinase (protein kinase A) and the calcium/ phospholipid-dependent protein kinase (protein kinase C). Microtubule protein phosphorylation has also been studied in neuronal cultures. In differentiated neuroblastoma cells, only MAP-1B and β-tubulin are phosphorylated in a manner coupled to neurite outgrowth. In primary cultures of fetal rat brain neurons, the pattern of microtubule protein phosphorylation resembles that found in vivo in rat pup brain. As phosphorylated MAP-1A and MAP-1B are present mainly on assembled microtubules, whereas the phosphorylation of MAP-2 decreases its interaction with microtubules, a role can be suggested for the phosphorylation of these proteins in the regulation of microtubule assembly and disassembly during neuronal development.