María Ángeles Herranz

Charge-transfer-induced structural rearrangements at both sides of organic/metal interfaces

Organic/metal interfaces control the performance of many optoelectronic organic devices, including organic light-emitting diodes or field-effect transistors. Using scanning tunnelling microscopy, low-energy electron diffraction, X-ray photoemission spectroscopy, near-edge X-ray absorption fine structure spectroscopy and density functional theory calculations, we show that electron transfer at the interface between a metal surface and the organic electron acceptor tetracyano-p-quinodimethane leads to substantial structural rearrangements on both the organic and metallic sides of the interface. These structural modifications mediate new intermolecular interactions through the creation of stress fields that could not have been predicted on the basis of gas-phase neutral tetracyano-p-quinodimethane conformation.

Metal Nitride Cluster Fullerene M3N@C80 (M=Y, Sc) Based Dyads: Synthesis, and Electrochemical, Theoretical and Photophysical Studies

The first pyrrolidine and cyclopropane derivatives of the trimetallic nitride templated (TNT) endohedral metallofullerenes I(h)-Sc(3)N@C(80) and I(h)-Y(3)N@C(80) connected to an electron-donor unit (i.e., tetrathiafulvalene, phthalocyanine or ferrocene) were successfully prepared by 1,3-dipolar cycloaddition reactions of azomethine ylides and Bingel-Hirsch-type reactions. Electrochemical studies confirmed the formation of the [6,6] regioisomers for the Y(3)N@C(80)-based dyads and the [5,6] regioisomers in the case of Sc(3)N@C(80)-based dyads. Similar to other TNT endohedral metallofullerene systems previously synthesized, irreversible reductive behavior was observed for the [6,6]-Y(3)N@C(80)-based dyads, whereas the [5,6]-Sc(3)N@C(80)-based dyads exhibited reversible reductive electrochemistry. Density functional calculations were also carried out on these dyads confirming the importance of these structures as electron transfer model systems. Furthermore, photophysical investigations on a ferrocenyl-Sc(3)N@C(80)-fulleropyrrolidine dyad demonstrated the existence of a photoinduced electron-transfer process that yields a radical ion pair with a lifetime three times longer than that obtained for the analogous C(60) dyad.

Screening Electronic Communication through ortho‐, meta‐ and para‐Substituted Linkers Separating Subphthalocyanines and C60

We have prepared two complementary series of SubPc-C(60) (SubPc=subphthalocyanine) electron/energy donor-acceptor systems, in which the two constituents are linked through ortho-, meta-, or para-substituted phenoxy spacers. In one of the series (1 a) the SubPc units bear iodine atoms, while in the other series (1 b) diphenylamino groups are linked to the SubPc macrocycles. The iodine atoms and diphenylamino groups both influence the resulting oxidation potentials of the electron-donating SubPc. They also modulate the outcome of excited state interactions, namely, energy and/or charge transfer. In addition, we have studied the impact that the substitution pattern in the phenoxy spacer exerts onto intramolecular processes in the ground and excited states. Although some of these processes are governed by the spatial separation between both components, the different electronic coupling through ortho-, meta-, or para- connections also plays decisive roles in some cases.

Metal ion recognition and molecular templating in self-assembled monolayers of cyclic and acyclic polyethers

Our recent work with cyclic and acyclic polyether self-assembled monolayers (SAMs) on gold is presented. A series of dithia-crown-tetrathiafulvalene derivatives with one or two disulfide groups has been prepared, and their SAMs on gold have been characterized by electrochemistry and by reflection–absorption infrared spectroscopy. These SAMs are extremely stable on repeated electrochemical potential scans and can selectively recognize alkali metal ions. Acyclic polyether derivatives can also self-assemble on gold to yield selective metal ion recognition domains. Impedance spectroscopy data for these SAMs fit the Langmuir isotherm and allow the determination of ion association constants. Some of the SAMs prepared with new acyclic polyether derivatives are able to detect potassium cations selectively when templated in their presence. These structures are believed to be a consequence of ion “imprinting” during the process of SAM formation.

Phylogeny of Kinorhyncha Based on Morphology and Two Molecular Loci

The phylogeny of Kinorhyncha was analyzed using morphology and the molecular loci 18S rRNA and 28S rRNA. The different datasets were analyzed separately and in combination, using maximum likelihood and Bayesian Inference. Bayesian inference of molecular sequence data in combination with morphology supported the division of Kinorhyncha into two major clades: Cyclorhagida comb. nov. and Allomalorhagida nom. nov. The latter clade represents a new kinorhynch class, and accommodates Dracoderes, Franciscideres, a yet undescribed genus which is closely related with Franciscideres, and the traditional homalorhagid genera. Homalorhagid monophyly was not supported by any analyses with molecular sequence data included. Analysis of the combined molecular and morphological data furthermore supported a cyclorhagid clade which included all traditional cyclorhagid taxa, except Dracoderes that no longer should be considered a cyclorhagid genus. Accordingly, Cyclorhagida is divided into three main lineages: Echinoderidae, Campyloderidae, and a large clade, ‘Kentrorhagata’, which except for species of Campyloderes, includes all species with a midterminal spine present in adult individuals. Maximum likelihood analysis of the combined datasets produced a rather unresolved tree that was not regarded in the following discussion. Results of the analyses with only molecular sequence data included were incongruent at different points. However, common for all analyses was the support of several major clades, i.e., Campyloderidae, Kentrorhagata, Echinoderidae, Dracoderidae, Pycnophyidae, and a clade with Paracentrophyes + New Genus and Franciscideres (in those analyses where the latter was included). All molecular analyses including 18S rRNA sequence data furthermore supported monophyly of Allomalorhagida. Cyclorhagid monophyly was only supported in analyses of combined 18S rRNA and 28S rRNA (both ML and BI), and only in a restricted dataset where taxa with incomplete information from 28S rRNA had been omitted. Analysis of the morphological data produced results that were similar with those from the combined molecular and morphological analysis. E.g., the morphological data also supported exclusion of Dracoderes from Cyclorhagida. The main differences between the morphological analysis and analyses based on the combined datasets include: 1) Homalorhagida appears as monophyletic in the morphological tree only, 2) the morphological analyses position Franciscideres and the new genus within Cyclorhagida near Zelinkaderidae and Cateriidae, whereas analyses including molecular data place the two genera inside Allomalorhagida, and 3) species of Campyloderes appear in a basal trichotomy within Kentrorhagata in the morphological tree, whereas analysis of the combined datasets places species of Campyloderes as a sister clade to Echinoderidae and Kentrorhagata.

Stable Electron Donor–Acceptor Nanohybrids by Interfacing n‐Type TCAQ with p‐Type Single‐Walled Carbon Nanotubes

Financial support from MINECO of Spain (CTQ2011-24652, PIB2010JP-00196, 2010C-07-25200, and Consolider- Ingenio CSD2007-00010), FUNMOLS (FP7-212942-1), CAM (MADRISOLAR-2 S2009/PPQ-1533), DFG (GU 517/16-1), and DFG (Excellence Cluster – Engineering of Advanced Materials) is greatly appreciated.

Video-games: Do they require general intelligence?

Here we test if playing video-games require intelligence. Twenty-seven university undergraduate students were trained on three games from Big Brain Academy (Wii): Calculus, Backward Memory and Train. Participants did not have any previous experience with these games. General intelligence was measured by five ability tests before the training session. Training comprised 10 blocks of trials (10 trials per block). Ackermans (Ackerman, P. L. (1988). Individual differences and skill acquisition. In P. L. Ackerman, R. J. Sernberg, & R. Glaser (Eds.), Learning and individual differences: Advances in theory and practice (pp. 165-217). New York: W.H. Freeman and Company) theory of skill learning was used as a framework for the present study. Results show that playing the Train game increases the correlation with general intelligence across blocks of trials. This is not the case for Calculus and Backward Memory. These findings suggest strategies for designing video-games presumably appropriate to stimulate our core cognitive abilities.

Enantiospecific cis-trans isomerization in chiral fulleropyrrolidines: hydrogen-bonding assistance in the carbanion stabilization in H2O@C60.

The stereochemical outcome of cis-trans isomerization of optically pure [60], [70], and endohedral H2O@C60 fulleropyrrolidines reveals that the electronic nature of substituents, fullerene size, and surprisingly the incarcerated water molecule plays a crucial role in this rearrangement process. Theoretical DFT calculations are in very good agreement with the experimental findings. On the basis of the experimental results and computational calculations, a plausible reaction mechanism involving the hydrogen-bonding assistance of the inner water molecule in the carbanion stabilization of endofullerene is proposed.

New π-extended tetrathiafulvalene-containing fulleropyrrolidine dyads endowed with vinyl spacers

Abstract The synthesis of novel C 60 -donor dyads in which the fulleropyrrolidine moiety is covalently attached to an π-extended tetrathiafulvalene analogue through an ethylenic spacer is described. The cyclic voltammetry confirms the redox reactivity of both donor and acceptor chromophores and the semiempirical PM3 theoretical calculations predict the existence of two conformational isomers. In the ground state, no evidence of charge transfer interaction was observed in solution. Upon excitation, the fullerene singlet excited state in C 60 -donor dyads is subject to a solvent-dependent, rapid fluorescence quenching, suggesting an intramolecular electron transfer.

New Data on the Genus Paracentrophyes (Homalorhagida, Kinorhyncha), with the Description of a New Species from the West Pacific~!2010-01-06~!2010-04-21~!2010-05-18~!

The kinorhynch genus Paracentrophyes currently consists of two species only: P. quadridentatus (Zelinka, 1928) from the Mediterranean Sea and P. praedictus Higgins, 1983 from Belize in the Caribbean. Both species have until now been recorded from their type localities only. In the present contribution a new species of Paracentrophyes, P. anurus sp. nov., is described from the Korea Strait. The species can be recognized by details in the mouth cone morphology, absence of perispinal setae in segment 10, and absence of a midterminal process in both sexes. Female specimens are furthermore characterized by the presence of an extraordinary long middorsal spine on segment 10, whereas males possess a midterminal type 3 sensory spot. Besides the recording of the new species, the occurrence of P. cf. quadridentatus is reported from two localities in the Atlantic Ocean (Faeroe Islands and Spain). The recorded specimens are described in detail, based on combined examinations with LM and SEM, and diagnostic traits for all three species of Paracentrophyes are discussed in light of the newly acquired information. Furthermore, an emended terminology for positions of cuticular trunk structures is proposed.