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Copyright of RILCE. Revista de Filología Hispánica is the property of Servicio de Publicaciones de la Universidad de Navarra, S.A. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Understanding the structural and magnetic properties in layered hybrid organic‐inorganic metal halide perovskites (HOIPs) is key for their design and integration in spin‐electronic devices. Here, a systematic study is conducted on ten compounds to understand the effect of the transition metal (Cu2+, Mn2+, Co2+), organic spacer (alkyl‐ and aryl‐ammonium), and perovskite phase (Ruddlesden‐Popper and Dion‐Jacobson) on the properties of these materials. Temperature‐dependent Raman measurements show that the crystals' structural phase transitions are triggered by the motional freedom of the organic cations as well as by the flexibility of the inorganic metal‐halide lattice. In the case of Cu2+ HOIPs, an increase of the in‐plane anisotropy and a reduction of the octahedra interlayer distance is found to change the behavior of the HOIP from that of a 2D ferromagnet to that of a quasi‐3D antiferromagnet. Mn2+ HOIPs show inherent antiferromagnetic octahedra intralayer interactions and a phenomenologically rich magnetism, presenting spin‐canting, spin‐flop transitions, and metamagnetism controlled by the crystal anisotropy. Co2+ crystals with non‐linked tetrahedra show a dominant paramagnetic behavior irrespective of the organic spacer and the perovskite phase. This study demonstrates that the chemical flexibility of HOIPs can be exploited to develop novel layered magnetic materials with tailored magnetic properties. [ABSTRACT FROM AUTHOR]

A series of rhodium and iridium complexes with a N‐heterocyclic carbene (NHC) ligand decorated with a perylene‐diimide‐pyrene moiety are described. Electrochemical studies reveal that the complexes can undergo two successive one‐electron reduction events, associated to the reduction of the PDI moiety attached to the NHC ligand. The reduction of the ligand produces a significant increase on its electron‐donating character, as observed from the infrared spectroelectrochemical studies. The rhodium complex was tested in the [3+2] cycloaddition of diphenylcyclopropenone and methylphenylacetylene, where it displayed a redox‐switchable behavior. The neutral complex showed moderate activity, which was suppressed when the catalyst was reduced. [ABSTRACT FROM AUTHOR]

Molecular nanoribbons are a class of atomically‐precise nanomaterials for a broad range of applications. An iterative approach that allows doubling the length of the longest pyrene‐pyrazinoquinoxaline molecular nanoribbons is described. The largest nanoribbon obtained through this approach—with a 60 linearly‐fused ring backbone (14.9 nm) and a 324‐atoms core (C276N48)—shows an extremely high molar absorptivity (values up to 1 198 074 M−1 cm−1) that also endows it with a high molar fluorescence brightness (8700 M−1 cm−1). [ABSTRACT FROM AUTHOR]

The chemical processing of low‐dimensional carbon nanostructures is crucial for their integration in future devices. Here we apply a new methodology in atomically precise engineering by combining multistep solution synthesis of N‐doped molecular graphene nanoribbons (GNRs) with mass‐selected ultra‐high vacuum electrospray controlled ion beam deposition on surfaces and real‐space visualisation by scanning tunnelling microscopy. We demonstrate how this method yields solely a controllable amount of single, otherwise unsublimable, GNRs of 2.9 nm length on a planar Ag(111) surface. This methodology allows for further processing by employing on‐surface synthesis protocols and exploiting the reactivity of the substrate. Following multiple chemical transformations, the GNRs provide reactive building blocks to form extended, metal–organic coordination polymers. [ABSTRACT FROM AUTHOR]

Two‐dimensional fused aromatic networks (2D FANs) have emerged as a highly versatile alternative to holey graphene. The synthesis of 2D FANs with increasingly larger lattice dimensions will enable new application perspectives. However, the synthesis of larger analogues is mostly limited by lack of appropriate monomers and methods. Herein, we describe the synthesis, characterisation and properties of an expanded 2D FAN with 90‐ring hexagons, which exceed the largest 2D FAN lattices reported to date. [ABSTRACT FROM AUTHOR]

Three‐dimensional covalent organic frameworks (3D COFs) with a pcu topology have been obtained from distorted polycyclic aromatic hydrocarbons acting as triangular antiprismatic (D3d) nodes. Such 3D COFs are six‐fold interpenetrated as the result of interframework π‐stacking, which enable charge transport properties that are not expected for 3D COFs. [ABSTRACT FROM AUTHOR]

Molecular packing and microstructure can play a crucial role in the photophysical and electronic properties of organic semiconductor materials. This article presents six pyrene‐fused dibenzoazatetracenes 3 and the relationship between their molecular structures and the emission, and as well as the morphology has been investigated. All of the compounds display an aggregation‐caused emission quenching effect due to the extended π‐conjugation associated with the close π‐π stacking in their crystal structures. In terms of fluorescence, the compounds emitted sky‐blue emission with a maximum peak (λmaxem) in the range 469–474 nm with a quantum yield (Φf) of 0.37–0.50 in solution. In the solid state, the emission maximum red‐shifts to ∼528 nm and possesses a relatively low quantum yield (<0.16). In addition, the electronic effects of the terminal group shows only a limited effect on the emission behavior. On the other hand, tert‐butyl groups have been introduced at the pyrene core, and contribute to enhance the solubility of the compound, and also improve the quality of the morphology. [ABSTRACT FROM AUTHOR]

A new strategy to obtain distorted pyrene-fused azaacenes is reported. The careful alignment and selection of substituents give rise to highly twisted pyrene-fused azaacenes. A combined global and local theoretical analysis shows how the strain is generated and dispersed across the aromatic backbone. Furthermore, simulation of the observed optoelectronic properties shines light on the structural factors that govern the properties of twisted pyrene-fused azaacenes. [ABSTRACT FROM AUTHOR]

The key electronic properties of a family of 2D frameworks structurally convergent with holey graphenes were studied. The bandgap of these materials decreases monotonically with size, showing a common trend with anthracenes and kekulenes. This was rationalized by Clar's sextet rule, which reveals a direct relationship between the molecular systems and the 2D frameworks. In addition, a detailed benchmark against experimental data showcased the high quality of the models, which reproduce accurately available electronic properties. Overall, it was shown that DFT can be used to screen and understand the intrinsic bandgaps and electrochemistry potentials for technological applications prior to the synthesis of π‐conjugated porous materials. [ABSTRACT FROM AUTHOR]

Singlet fission has emerged as a promising strategy to avoid the loss of extra energy through thermalization in solar cells. A family of dimers consisting of nitrogen‐doped pyrene‐fused acenes that undergo singlet fission with triplet quantum yields as high as 125 % are presented. They provide new perspectives for nitrogenated polycyclic aromatic hydrocarbons and for the design of new materials for singlet fission. [ABSTRACT FROM AUTHOR]

Supramolecular polymers show great potential in the development of new materials because of their inherent recyclability and their self‐healing and stimuli‐responsive properties. Supramolecular conductive polymers are generally obtained by the assembly of individual aromatic molecules into columnar arrays that provide an optimal channel for electronic transport. A new approach is reported to prepare supramolecular polymers by hooking together sigmoidal monomers into 1D arrays of π‐stacked anthracene and acridine units, which gives rise to micrometer‐sized fibrils that show pseudoconductivities in line with other conducting materials. This approach paves the way for the design of new supramolecular polymers constituted by acene derivatives with enhanced excitonic and electronic transporting properties. [ABSTRACT FROM AUTHOR]

Controlled nitrogen‐doping is a powerful methodology to modify the properties of carbon nanostructures and produce functional materials for electrocatalysis, energy conversion and storage, and sensing, among others. Herein, we report a wall‐ and hybridisation‐selective synthetic methodology to produce double‐walled carbon nanotubes with an inner tube doped exclusively with graphitic sp2‐nitrogen atoms. Our measurements shed light on the fundamental properties of nitrogen‐doped nanocarbons opening the door for developing their potential applications. [ABSTRACT FROM AUTHOR]

Considerable research efforts have been devoted to the development of rotaxanes and the study of their unique dynamic properties. This minireview provides an overview of the main advances that have been realized in rotaxane architectures involving different types of carbon nanostructures. In particular, rotaxanes based on fullerenes and carbon nanotubes will be discussed. [ABSTRACT FROM AUTHOR]

Herein, we describe the synthesis of a hole transporting material based on a partially planarised quart-p-phenylene core incorporating tetraketal and diphenylamine substituents that show optimal energy levels and solubility for perovskite solar cell applications. The triple-cation perovskite devices incorporating such quart-p-phenylene derivatives show power-conversion efficiencies, short circuit currents, open circuit voltages, and fill factors that are comparable to those of spiro-OMeTAD. [ABSTRACT FROM AUTHOR]

Copyright of Angewandte Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The development of organic electronics requires scalable solution‐processing methods that enable the fabrication of electronic devices over large areas at low cost. The preparation of peropyrene gels constituted of 3D networks of entangled 1D ribbon‐like fibrils that extend over the μm scale are now reported. OFETs were easily fabricated by depositing the gels in the sol state over bottom‐gate bottom‐contact transistors and by allowing its gelation thereafter. Electrical characterisation of such field‐effect transistors shows a good balance between processability and performance with hole mobilities that are two orders of magnitude higher than those observed in thin films obtained from non‐gelating solvents under the same conditions. [ABSTRACT FROM AUTHOR]

Copyright of RILCE. Revista de Filología Hispánica is the property of Servicio de Publicaciones de la Universidad de Navarra, S.A. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: The properties of graphene nanoribbons are highly dependent on structural variables such as width, length, edge structure, and heteroatom doping. Therefore, atomic precision over all these variables is necessary for establishing their fundamental properties and exploring their potential applications. An iterative approach is presented that assembles a small and carefully designed molecular building block into monodisperse N‐doped graphene nanoribbons with different lengths. To showcase this approach, the synthesis and characterisation of a series of nanoribbons constituted of 10, 20 and 30 conjugated linearly‐fused rings (2.9, 5.3, and 7.7 nm in length, respectively) is presented. [ABSTRACT FROM AUTHOR]

This microreview covers the different synthetic strategies used to prepare pyrene-fused twistacenes. [ABSTRACT FROM AUTHOR]

Twisted two-dimensional aromatic frameworks have been prepared by overcrowding the nodes with bulky and rigid substituents. The highly distorted aromatic framework with alternating out-of-plane substituents results in diminished interlayer interactions that favor the exfoliation and dispersion of individual layers in organic media. [ABSTRACT FROM AUTHOR]

Copyright of BSAA Arte is the property of Universidad de Valladolid and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)