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Chiral molecules are known to behave as spin filters due to the chiral induced spin selectivity (CISS) effect. Chirality can be implemented in molecular semiconductors in order to study the role of the CISS effect in charge transport and to find new materials for spintronic applications. In this study, the design and synthesis of a new class of enantiopure chiral organic semiconductors based on the well-known dinaphtho[2,3-b:2,3-f]thieno[3,2-b]thiophene (DNTT) core functionalized with chiral alkyl side chains is presented. When introduced in an organic field-effect transistor (OFET) with magnetic contacts, the two enantiomers, (R)-DNTT and (S)-DNTT, show an opposite behavior with respect to the relative direction of the magnetization of the contacts, oriented by an external magnetic field. Each enantiomer displays an unexpectedly high magnetoresistance over one preferred orientation of the spin current injected from the magnetic contacts. The result is the first reported OFET in which the current can be switched on and off upon inversion of the direction of the applied external magnetic field. This work contributes to the general understanding of the CISS effect and opens new avenues for the introduction of organic materials in spintronic devices., SCOPUS: ar.j, info:eu-repo/semantics/published

We report the polymorph investigation, crystallographic study and fabrication of organic field-effect transistors (OFETs) in solution-processed thin films of a prototypical organic semiconductor, i.e. 2,7-diheptylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene (C7-BTBT-C7). We found that this molecule self-assembles solely into one type of stable crystal form, regardless of the experimental conditions employed when using conventional and non-conventional methods of crystallization. The integration of blends of C7-BTBT-C7 with polystyrene as active materials in OFETs fabricated using a solution shearing technique led to a field-effect mobility of 1.42 ± 0.45 cm2 V−1 s−1 in the saturation regime when a coating speed of 10 mm s−1 was employed. The intrinsic structural properties control the overlap of the frontier orbitals, thereby affecting the device performance. The interplay between the crystal packing, thin film morphology and uniformity and its impact on the device performance are reported., info:eu-repo/semantics/published

We report the polymorph investigation, crystallographic study and fabrication of organic field-effect transistors (OFETs) in solution-processed thin films of a prototypical organic semiconductor, i.e., 2,7-diheptylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene (C7-BTBT-C7). We found that this molecule self-assembles solely into one type of stable crystal form, regardless of the experimental conditions employed when using conventional and non-conventional methods of crystallization. The integration of blends of C7-BTBT-C7 with polystyrene as active materials in OFETs fabricated using a solution shearing technique led to a field-effect mobility of 1.42 ± 0.45 cm2 V−1 s−1 in the saturation regime when a coating speed of 10 mm s−1 was employed. The intrinsic structural properties control the overlap of the frontier orbitals, thereby affecting the device performance. The interplay between the crystal packing, thin film morphology and uniformity and its impact on the device performance are reported.

We combine temperature-dependent low-frequency Raman measurements and first-principles calculations to obtain a mechanistic understanding of the order–disorder phase transition of 2,7-di-tert-butylbenzo[b]benzo[4,5]thieno[2,3-d]thiophene (ditBu-BTBT) and 6,13-bis(triisopropylsilylethynyl) pentacene (TIPS-pentacene) semiconducting amphidynamic crystals. We identify the lattice normal modes associated with the phase transition by following the position and width of the Raman peaks with temperature and identifying peaks that exhibit nonlinear dependence toward the phase transition temperature. Our findings are interpreted according to the “hardcore mode” model previously used to describe order–disorder phase transitions in inorganic and hybrid crystals with a Brownian sublattice. Within the framework of this model, ditBu-BTBT exhibits an ideal behavior where only one lattice mode is associated with the phase transition. TIPS-pentacene deviates strongly from the model due to strong interactions between lattice modes. We discuss the origin of the different behaviors and suggest side-chain engineering as a tool to control polymorphism in amphidynamic crystals., SCOPUS: ar.j, info:eu-repo/semantics/published

info:eu-repo/semantics/published

Single crystals of novel (C 8 O-BTBT-OC 8 )(F x TCNQ) charge complexes (CT) are prepared and fully characterised. Solution processed films of the (C 8 O-BTBT-OC 8 )(F 4 TCNQ) CT are implemented in organic field-effect transistors giving an n-type behaviour., info:eu-repo/semantics/published

Herein, we report on the synthesis and structural characterization of novel charge transfer (CT) complexes of the benzothienobenzothiophene derivative C8O-BTBT-OC8 with the series of FxTCNQ derivatives (x = 2, 4). The degree of charge transfer and HOMO–LUMO gap energies were evaluated by spectroscopic means and by DFT calculations. Thin films of the (C8O-BTBT-OC8)(F4TCNQ) complex were prepared by a simple solution shearing technique and by blending the active materials with polystyrene. X-Ray diffraction and IR/Raman spectroscopy techniques were instrumental for the structural identification of the films, which belonged to the same phase as the resolved single crystal. The films were implemented as an active layer in organic field-effect transistor (OFET) devices, which exhibited an n-type behavior in ambient conditions in agreement with the theoretical calculations.

Although its intensity and duration, the relation between Elsa Morante and the cinema is less studied by the critics, perhaps because of the scarceness of information. But the discovery of many new documents in these years permitted to know the plots written (but not realized9 by the Author from 1933 till 1952 (there are three different plots: Il diavolo, Miss Italia and Verranno a te sull’aure). It is also possible to have a clear idea of the collaboration with some directors like: Alberto Lattuada, Luchino Visconti, Franco Zeffirelli, Pier Paolo Pasolini. A close analysis of the cinematographic version of the novel L’Isola di Arturo, directed by Damiano Damiani in 1962, permits to determine that the dissatisfaction which Morante expressed in many circumstances derives from a lack of dialogue between her and the director damiano Damiani., Pure se intenso e continuato nel tempo, il rapporto tra Elsa Morante e il cinema è sempre rimasto un argomento poco sondato dalla critica, forse anche per la scarsità di informazioni al riguardo. Negli ultimi anni, tuttavia, molti nuovi documenti sono stati reperiti, e tali scoperte hanno reso possibile conoscere i soggetti cinematografici da lei scritti (ma mai realizzati) tra il 1939 e il 1952 (sono tre: Il diavolo, Miss Italia e Verranno a te sull’aure...), nonché farsi un’idea concreta delle sue varie collaborazioni con registi come Alberto Lattuada, Luchino Visconti, Franco Zeffirelli, Pier Paolo Pasolini. Differentemente, un’analisi attenta della trasposizione cinematografica de L’isola di Arturo, diretta da Damiano Damiani nel 1962, mostra come l’esibita insoddisfazione della scrittrice, espressa in più occasioni, nasca per l’appunto da un’assenza di dialogo tra i due artisti.