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Ambipolar organic field-effect transistors (OFETs), which can efficiently transport both holes and electrons, using a single type of electrode, are currently of great interest due to their possible applications in complementary metal oxide semiconductor (CMOS)-like circuits, sensors, and in light-emitting transistors. Several theoretical and experimental studies have argued that most organic semiconductors should be able to transport both types of carrier, although typically unipolar behavior is observed. One factor that can compromise ambipolar transport in organic semiconductors is poor solid state overlap between the HOMO (p-type) or LUMO (n-type) orbitals of neighboring molecules in the semiconductor thin film. In the search of low-bandgap ambipolar materials, where the absence of skeletal distortions allows closer intermolecular π-π stacking and enhanced intramolecular π-conjugation, a new family of oligothiophene-naphthalimide assemblies have been synthesized and characterized, in which both donor and acceptor moieties are directly conjugated through rigid linkers. In previous works we found that oligothiophene-napthalimide assemblies connected through amidine linkers (NDI derivates) exhibit skeletal distortions (50-60º) arising from steric hindrance between the carbonyl group of the arylene core and the sulphur atom of the neighbored thiophene ring. In the present work we report novel oligo- and polythiophene–naphthalimide analogues NAI-3T, NAI-5T and poly-NAI-8C-3T, in which the connections of the amidine linkage have been inverted in order to prevent steric interactions. Thus, the nitrogen atoms are directly connected to the naphthalene moiety in NAI derivatives while they were attached directly to the thiophene moiety in the previously investigated NDI-3T and NDI-5T. The calculated molecular structure of NAI-3T together shows how the steric interactions are not present in the novel NAI derivative. The planar skeletons in these new family induce higher degree of crystallinity and the carrier charge transport can be switched from n-type to ambipolar behaviour. The highest FET performance is achieved for vapor-deposited films of NAI-3T with mobilities of 1.95x10-4cm2V-1s-1 and 2.00x10-4cm2V-1s-1 for electrons and holes, respectively. Finally, these planar semiconductors are compared with their NDI derivates analogues, which exhibit only n-type mobility, in order to understand the origin of the ambipolarity in this new series of molecular semiconductors. Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

The author of Vita Fructuosi, probably a monk follower of Saint Fructuosus of Braga in the area of Gallaecia, shows in this biography an evident sense of rooting in the monastic Tradition, specially in the Egyptianeastern one, and also he declares a strong Roman-Catholic and Hispanic conscience. As the highest expression of it, he presents Saint Fructuosus with the same merits of the Egyptian monks and, joined to Saint Isidorus of Seville, as a light for Spain, for the Western and for the whole Catholic Church: they both are two causes of glory for a Visigothic Spain which fells herself as Roman and Catholic.El autor de la Vita Fructuosi, al parecer un monje discípulo de San Fructuoso de Braga en el área de Gallaecia, muestra en esta biografía un claro sentido de arraigo en la Tradición monástica, especialmente egipcio-oriental, y manifiesta una fuerte conciencia romano-católica e hispana. Como máxima expresión de todo ello, presenta a San Fructuoso a la altura de los méritos de los monjes egipcios y, junto con San Isidoro de Sevilla, como una lumbrera de Hispania, del Occidente y de toda la Iglesia Católica: ambos son dos motivos de gloria de la Hispania visigótica que se siente romana y católica.