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1. Diffusion-free photon upconversion driven by intramolecular triplet-triplet annihilation in engineered conjugated chromophores

Author

Mattiello, Sara, Mecca, Sara, Ronchi, Alessandra, Calascibetta, Adiel, Mattioli, Giuseppe, Pallini, Francesca, Meinardi, Francesco, Beverina, Luca, and Monguzzi, Angelo

Subjects
Condensed Matter - Materials Science
Abstract

The photon upconversion based on sensitized triplet-triplet annihilation (sTTA-UC) is a spin-flip mechanism exploited to recover the energy of dark triplet states in conjugated systems. In this process a high-energy fluorescent singlet is created through the collision and fusion of two low-energy triplets belonging to different diffusing molecules. Its excellent yield in solution under low excitation intensity and non-coherent light highlighted the huge potential of sTTA-UC to provide a breakthrough in solar technologies. However, its diffusion-limited bi-molecular nature limits its efficiency in the solid state. To overcome this issue, we designed a molecular systems able to host simultaneously more than one triplet, thus enabling a diffusion-free intramolecular TTA. We obtain the first direct demonstration of intramolecular triplet fusion by tailored photoluminescence spectroscopy experiments, thus opening the way to realize a new family of single molecule upconverters with huge potential in solar and lightening technologies by accessing the natural triplets energy reservoir.

Published
2022

2. Ab initio Circular Dichroism with the Yambo code: beyond the Independent Particle approximation

Author

Molteni, Elena, Mattioli, Giuseppe, and Sangalli, Davide

Subjects
Physics - Chemical Physics
Abstract

Circular dichroism (CD) spectroscopy is a useful technique for characterizing chiral molecules. It is more sensitive than total absorption to molecule conformation, and it is routinely used to identify enantiomers. We present here absorption and CD spectra within the Time Dependent (TD) B3LYP approximation in c-GlyPhe, a cyclo-dipeptide containing an aromatic group. Results from codes in localized basis-set (Orca and MolGW) are carefully compared with the novel TD-B3LYP implementation we developed in the Yambo code, that uses a plane-wave basis set., Comment: 5 pages, 2 figures

Published
2022
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3. A systematic study of the valence electronic structure of cyclo(Gly-Phe), cyclo(Trp-Tyr) and cyclo(Trp-Trp) dipeptides in gas phase

Author

Molteni, Elena, Mattioli, Giuseppe, Alippi, Paola, Avaldi, Lorenzo, Bolognesi, Paola, Carlini, Laura, Vismarra, Federico, Wu, Yingxuan, Varillas, Rocio Borrego, Nisoli, Mauro, Singh, Manjot, Valadan, Mohammadhassan, Altucci, Carlo, Richter, Robert, and Sangalli, Davide

Subjects
Physics - Chemical Physics
Abstract

The electronic energy levels of cyclo(Glycine-Phenylalanine), cyclo(Tryptophan-Tyrosine) and cyclo(Tryptophan-Tryptophan) dipeptides are investigated with a joint experimental and theoretical approach. Experimentally, valence photoelectron spectra in the gas phase are measured using VUV radiation. Theoretically, we first obtain low-energy conformers through an automated conformer-rotamer ensemble sampling scheme based on tight-binding simulations. Then, different first principles computational schemes are considered to simulate the spectra: Hartree-Fock (HF), density functional theory (DFT) within the B3LYP approximation, the quasi--particle GW correction, and the quantum-chemistry CCSD method. Theory allows to assign the main features of the spectra. A discussion on the role of electronic correlation is provided, by comparing computationally cheaper DFT scheme (and GW) results with the accurate CCSD method., Comment: 21 pages, 16 figures (including Supplementary Information)

Published
2021
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4. Improved Charge Recombination Efficiency in Organic Light‐Emitting Transistors via Luminescent Radicals.

Author

Reginato, Francesco, Lunedei, Eugenio, Mattiello, Sara, Baroni, Giulia, Bolognesi, Margherita, Porcelli, Francesco, Mattioli, Giuseppe, Hattori, Yohei, Prosa, Mario, Beverina, Luca, and Toffanin, Stefano

Abstract

Luminescent radicals are attracting attention as emitters in electroluminescent devices thanks to the exploitation of doublet excitons. Recent studies reveal that exciton formation in radical organic light‐emitting diodes (OLEDs) primarily occurs through a charge trapping mechanism. Although typically detrimental for OLEDs, this might be a key process to elucidate light emission in organic light‐emitting transistors (OLETs). Here, a unipolar n‐type architecture suitable for the implementation of radical emitters is introduced, designed based on computational calculations. The operation of the as‐realized devices incorporating the newly synthesized [2,6‐dichloro‐4‐(2,6‐dimethoxyphenyl)phenyl](3,5‐dichloro‐4‐pyridyl) (2,4,6‐trichlorophenyl)methyl radical is investigated via transient electroluminescence measurements to demonstrate the occurrence of long‐living emission ascribed to the charge trapping mechanisms. Moreover, a comprehensive understanding of the processes governing radical‐OLET is obtained by recording complete 2D maps of both optical and electrical response of the device as a function of applied voltages. Notably, the trapping of electrons by radical moieties is demonstrated to generate a negative charge density in the emissive layer that facilitates holes to be injected: increasing the balance of opposite charge carriers, a tenfold enhancement of the external quantum efficiency (EQE) at the proper source‐drain and source‐gate voltage conditions is reported to reach a maximum EQE value of 0.2%. [ABSTRACT FROM AUTHOR]

Published
2025
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5. Glycerol as Reaction Medium for Sonogashira Couplings: A Green Approach for the Synthesis of New Triarylamine‐Based Materials with Potential Application in Optoelectronics.

Author

Raglione, Venanzio, Palmeri, Federica, Mattioli, Giuseppe, Porcelli, Francesco, Caschera, Daniela, and Zanotti, Gloria

Subjects
SUSTAINABLE chemistry, ORGANIC solvents, SOLAR concentrators, SONOGASHIRA reaction, ARYL iodides
Abstract

This study focuses on the design, eco‐friendly synthesis, and characterization of several novel three‐legged triphenylamine derivatives. By performing Sonogashira couplings of functionalized aryl iodides with tris(4‐ethynylphenyl)amine in glycerol, a readily available bio‐derived solvent, we achieved the synthesis of target products in short times and high yields, up to 94 %, with consistently lower E‐factors and reduced costs compared to standard conditions using toluene as the reaction medium. The target molecules possess a D‐(π‐A)₃ or D‐(π‐D)₃ structure, where an electron‐donating core connects to three electron‐donating (D) or electron‐accepting (A) peripheral aromatic subunits through an acetylene spacer. Their main optical and electronic properties have been determined experimentally and by DFT simulations and suggest a possible implementation in energy conversion technologies such as luminescent solar concentrators (LSCs) and perovskite solar cells (PSCs). [ABSTRACT FROM AUTHOR]

Published
2024
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6. Nanoactuator for Neuronal Optoporation

Author

Pfeffer, Marlene E., primary, DiFrancesco, Mattia Lorenzo, additional, Marchesi, Arin, additional, Galluzzi, Filippo, additional, Moschetta, Matteo, additional, Rossini, Andrea, additional, Francia, Simona, additional, Franz, Clemens, additional, Fok, Yulia, additional, Valotteau, Claire, additional, Paternò, Giuseppe Maria, additional, Redondo Morata, Lorena, additional, Vacca, Francesca, additional, Mattiello, Sara, additional, Magni, Arianna, additional, Maragliano, Luca, additional, Beverina, Luca, additional, Mattioli, Giuseppe, additional, Lanzani, Guglielmo, additional, Baldelli, Pietro, additional, Colombo, Elisabetta, additional, and Benfenati, Fabio, additional

Published
2024
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7. A study of the valence photoelectron spectrum of uracil and mixed water–uracil clusters.

Author

Mattioli, Giuseppe, Avaldi, Lorenzo, Bolognesi, Paola, Casavola, Annarita, Morini, Filippo, Van Caekenberghe, Thomas, Bozek, John D., Castrovilli, Mattea C., Chiarinelli, Jacopo, Domaracka, Alicja, Indrajith, Suvasthika, Maclot, Sylvain, Milosavljević, Aleksandar R., Nicolafrancesco, Chiara, Nicolas, Christophe, and Rousseau, Patrick

Subjects
*PHOTOELECTRON spectra, *URACIL, *NATURAL orbitals, *AB-initio calculations, *IONIZATION energy
Abstract

The valence ionization of uracil and mixed water–uracil clusters has been studied experimentally and by ab initio calculations. In both measurements, the spectrum onset shows a red shift with respect to the uracil molecule, with the mixed cluster characterized by peculiar features unexplained by the sum of independent contributions of the water or uracil aggregation. To interpret and assign all the contributions, we performed a series of multi-level calculations, starting from an exploration of several cluster structures using automated conformer-search algorithms based on a tight-binding approach. Ionization energies have been assessed on smaller clusters via a comparison between accurate wavefunction-based approaches and cost-effective DFT-based simulations, the latter of which were applied to clusters up to 12 uracil and 36 water molecules. The results confirm that (i) the bottom-up approach based on a multilevel method [Mattioli et al. Phys. Chem. Chem. Phys. 23, 1859 (2021)] to the structure of neutral clusters of unknown experimental composition converges to precise structure–property relationships and (ii) the coexistence of pure and mixed clusters in the water–uracil samples. A natural bond orbital (NBO) analysis performed on a subset of clusters highlighted the special role of H-bonds in the formation of the aggregates. The NBO analysis yields second-order perturbative energy between the H-bond donor and acceptor orbitals correlated with the calculated ionization energies. This sheds light on the role of the oxygen lone-pairs of the uracil CO group in the formation of strong H-bonds, with a stronger directionality in mixed clusters, giving a quantitative explanation for the formation of core–shell structures. [ABSTRACT FROM AUTHOR]

Published
2023
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10. Enhancing Hole Transfer in Perovskite Solar Cell with Self Assembled Monolayer by Introducing [1]benzothieno [3,2‐b] [1] benzothiophene Interlayer

Author

Takhellambam, Daimiota, primary, Castriotta, Luigi Angelo, additional, Zanotti, Gloria, additional, Mancini, Laura, additional, Raglione, Venanzio, additional, Mattioli, Giuseppe, additional, Paci, Barbara, additional, Generosi, Amanda, additional, Guaragno, Marco, additional, Campanari, Valerio, additional, Ammirati, Giuseppe, additional, Martelli, Faustino, additional, Calabrò, Emanuele, additional, Cricenti, Antonio, additional, Luce, Marco, additional, Nia, Narges Yaghoobi, additional, Di Giacomo, Francesco, additional, and Di Carlo, Aldo, additional

Published
2023
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12. Inner-shell photoelectron spectroscopy unveils the interplay between hydrogen bonds and π−π stacking in clusters of biomolecules in the gas phase: hypoxanthine clusters as a case study.

Author

Barreiro-Lage, Darío, Mattioli, Giuseppe, Nicolafrancesco, Chiara, Rousseau, Patrick, Milosavljević, Aleksandar R, and Díaz-Tendero, Sergio

Abstract

We present a joint theoretical-experimental study on the inner-shell photoionization of hypoxanthine clusters in the gas phase. Simulations were performed using a computational strategy that combines molecular dynamics to explore the conformers of the clusters, density functional theory for geometry optimization and inner shell photoionization calculations. Two main intermolecular interactions are observed: hydrogen-bonds (HB) and π − π stacking. When increasing the cluster size, a combination of both kinds of interaction occurs. We show that such intermolecular interactions play a role in the chemical shift observed in X-ray photoemission spectroscopy experiments. In particular, we highlight the interplay between charge depletion and charge accumulation in regions where HBs stabilize the clusters. [ABSTRACT FROM AUTHOR]

Published
2024
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13. Enhancing Hole Transfer in Perovskite Solar Cell with Self-Assembled Monolayer by Introducing [1]Benzothieno [3,2-b][1]Benzothiophene Interlayer.

Author

Takhellambam, Daimiota, Castriotta, Luigi Angelo, Zanotti, Gloria, Mancini, Laura, Raglione, Venanzio, Mattioli, Giuseppe, Paci, Barbara, Generosi, Amanda, Guaragno, Marco, Campanari, Valerio, Ammirati, Giuseppe, Martelli, Faustino, Calabrò, Emanuele, Cricenti, Antonio, Luce, Marco, Nia, Narges Yaghoobi, Di Giacomo, Francesco, and Di Carlo, Aldo

Subjects
SOLAR cells, LIFE sciences, MONOMOLECULAR films, PEROVSKITE, FRONTIER orbitals, DIMETHYL sulfoxide
Abstract

The article offers information on the advancements in perovskite solar cells (PSCs), emphasizing their efficiency improvements over the past decade. Topics include the exploration of various strategies to enhance the quality of the perovskite layer, such as using excess precursors, additives, or passivating agents.

Published
2023
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14. Coverage-Dependent Modulation of Charge Density at the Interface between Ag(001) and Ruthenium Phthalocyanine

Author

Mattioli, Giuseppe, primary, Contini, Giorgio, additional, Ronci, Fabio, additional, Flammini, Roberto, additional, Frezza, Federico, additional, Larciprete, Rosanna, additional, Raglione, Venanzio, additional, Alippi, Paola, additional, Filippone, Francesco, additional, Bonapasta, Aldo Amore, additional, Zanotti, Gloria, additional, Kierren, Bertrand, additional, Moreau, Luc, additional, Pierron, Thomas, additional, Fagot-Revurat, Yannick, additional, and Colonna, Stefano, additional

Published
2023
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17. Diffusion-Free Intramolecular Triplet–Triplet Annihilation in Engineered Conjugated Chromophores for Sensitized Photon Upconversion

Author

Mattiello, S, Mecca, S, Ronchi, A, Calascibetta, A, Mattioli, G, Pallini, F, Meinardi, F, Beverina, L, Monguzzi, A, Mattiello, Sara, Mecca, Sara, Ronchi, Alessandra, Calascibetta, Adiel, Mattioli, Giuseppe, Pallini, Francesca, Meinardi, Francesco, Beverina, Luca, Monguzzi, Angelo, Mattiello, S, Mecca, S, Ronchi, A, Calascibetta, A, Mattioli, G, Pallini, F, Meinardi, F, Beverina, L, Monguzzi, A, Mattiello, Sara, Mecca, Sara, Ronchi, Alessandra, Calascibetta, Adiel, Mattioli, Giuseppe, Pallini, Francesca, Meinardi, Francesco, Beverina, Luca, and Monguzzi, Angelo

Abstract

The photon upconversion based on sensitized triplet–triplet annihilation (sTTA-UC) is a spin-flip mechanism exploited to recover the energy stored on dark triplet states in conjugated systems. In this process, a high-energy fluorescent singlet is created through the collision and fusion of two low-energy triplets belonging to different diffusing molecules. Its high yield in solution under low excitation intensity and noncoherent light highlighted the huge potential of sTTA-UC to provide a breakthrough in solar technologies. However, its diffusion-limited nature restrains its efficiency in the solid state. To overcome this issue, we propose a single-molecule system that is able to host simultaneously more than one triplet, thus enabling a diffusion-free intramolecular TTA. We obtain the first direct demonstration of intramolecular triplet fusion by tailored photoluminescence spectroscopy experiments, thus opening the way to realize a new family of single-molecule upconverters with huge potential in solar and lighting technologies by accessing the natural triplets’ energy reservoir.

Published
2022

20. Water–biomolecule clusters studied by photoemission spectroscopy and multilevel atomistic simulations: hydration or solvation?

Author

Mattioli, Giuseppe, Avaldi, Lorenzo, Bolognesi, Paola, Bozek, John, Castrovilli, Mattea, Chiarinelli, Jacopo, Domaracka, Alicja, Indrajith, Suvasthika, Maclot, Sylvain, Milosavljević, Aleksandar, Nicolafrancesco, Chiara, Rousseau, Patrick, Istituto di Struttura della Materia (CNR-ISM), Consiglio Nazionale delle Ricerche [Roma] (CNR), Synchrotron SOLEIL (SSOLEIL), Centre National de la Recherche Scientifique (CNRS), Centre de recherche sur les Ions, les MAtériaux et la Photonique (CIMAP - UMR 6252), Université de Caen Normandie (UNICAEN), Normandie Université (NU)-Normandie Université (NU)-École Nationale Supérieure d'Ingénieurs de Caen (ENSICAEN), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS), Normandie Université (NU), University of Gothenburg (GU), National Research Council of Italy | Consiglio Nazionale delle Ricerche (CNR), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Centre National de la Recherche Scientifique (CNRS)-Institut de Recherche sur les Matériaux Avancés (IRMA), Normandie Université (NU)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Institut national des sciences appliquées Rouen Normandie (INSA Rouen Normandie), Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Rouen Normandie (UNIROUEN), and Institut National des Sciences Appliquées (INSA)-Normandie Université (NU)-Institut National des Sciences Appliquées (INSA)-Centre National de la Recherche Scientifique (CNRS)

Subjects
[PHYS]Physics [physics]
Abstract

International audience; The properties of mixed water–uracil nanoaggregates have been probed by core electron–photoemission measurements to investigate supramolecular assembly in the gas phase driven by weak interactions. The interpretation of the measurements has been assisted by multilevel atomistic simulations, based on semi-empirical tight-binding and DFT-based methods. Our protocol established a positive-feedback loop between experimental and computational techniques, which has enabled a sound and detailed atomistic description of such complex heterogeneous molecular aggregates. Among biomolecules, uracil offers interesting and generalized skeletal features; its structure encompasses an alternation of hydrophilic H-bond donor and acceptor sites and hydrophobic moieties, typical in biomolecular systems, that induces a supramolecular core–shell-like organization of the mixed clusters with a water core and an uracil shell. This structure is far from typical models of both solid-state hydration, with water molecules in defined positions, or liquid solvation, where disconnected uracil molecules are completely surrounded by water.

Published
2021
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21. Selective Effects of the Host Matrix in Hydrogenated InGaAsN Alloys: Toward an Integrated Matrix/Defect Engineering Paradigm

Author

Filippone, Francesco, primary, Younis, Saeed, additional, Mattioli, Giuseppe, additional, Felici, Marco, additional, Blundo, Elena, additional, Polimeni, Antonio, additional, Pettinari, Giorgio, additional, Giubertoni, Damiano, additional, Sterzer, Eduard, additional, Volz, Kerstin, additional, Fekete, Dan, additional, Kapon, Eli, additional, and Amore Bonapasta, Aldo, additional

Published
2021
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24. Reaction intermediates in the photoreduction of oxygen molecules at the (101) Ti[O.sub.2] (anatase) surface

Author

Mattioli, Giuseppe, Filippone, Francesco, and Bonapasta, Aldo Amore

Subjects
Density functionals -- Usage, Titanium dioxide -- Chemical properties, Oxidation-reduction reaction -- Research, Chemistry
Abstract

The structural, electronic, and vibrational properties of intermediates of the [O.sub.2] photoreduction at the (101) Ti[O.sub.2] anatase surface were investigated by performing ab initio density functional calculations. The location and donor/acceptor character of the electronic levels induced by an adsorbed molecule in the Ti[O.sub.2] energy, both crucial for the surface-molecule charge transfer processes, were successfully estimated.

Published
2006

28. A systematic study of the valence electronic structure of cyclo(Gly–Phe), cyclo(Trp–Tyr) and cyclo(Trp–Trp) dipeptides in the gas phase

Author

Molteni, Elena, primary, Mattioli, Giuseppe, additional, Alippi, Paola, additional, Avaldi, Lorenzo, additional, Bolognesi, Paola, additional, Carlini, Laura, additional, Vismarra, Federico, additional, Wu, Yingxuan, additional, Varillas, Rocio Borrego, additional, Nisoli, Mauro, additional, Singh, Manjot, additional, Valadan, Mohammadhassan, additional, Altucci, Carlo, additional, Richter, Robert, additional, and Sangalli, Davide, additional

Published
2021
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30. Cover Feature: [1]Benzothieno[3,2‐b][1]benzothiophene‐Phthalocyanine Derivatives: A Subclass of Solution‐Processable Electron‐Rich Hole Transport Materials (ChemPlusChem 11/2020)

Author

Zanotti, Gloria, primary, Angelini, Nicola, additional, Mattioli, Giuseppe, additional, Paoletti, Anna Maria, additional, Pennesi, Giovanna, additional, Caschera, Daniela, additional, Sobolev, Anatoly Petrovich, additional, Beverina, Luca, additional, Calascibetta, Adiel Mauro, additional, Sanzone, Alessandro, additional, Di Carlo, Aldo, additional, Berionni Berna, Beatrice, additional, Pescetelli, Sara, additional, and Agresti, Antonio, additional

Published
2020
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31. Chemically Sustainable Large Stokes Shift Derivatives for High-Performance Large-Area Transparent Luminescent Solar Concentrators

Author

Mattiello, Sara, primary, Sanzone, Alessandro, additional, Bruni, Francesco, additional, Gandini, Marina, additional, Pinchetti, Valerio, additional, Monguzzi, Angelo, additional, Facchinetti, Irene, additional, Ruffo, Riccardo, additional, Meinardi, Francesco, additional, Mattioli, Giuseppe, additional, Sassi, Mauro, additional, Brovelli, Sergio, additional, and Beverina, Luca, additional

Published
2020
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33. [1]Benzothieno[3,2‐b][1]benzothiophene‐Phthalocyanine Derivatives: A Subclass of Solution‐Processable Electron‐Rich Hole Transport Materials

Author

Zanotti, Gloria, primary, Angelini, Nicola, additional, Mattioli, Giuseppe, additional, Paoletti, Anna Maria, additional, Pennesi, Giovanna, additional, Caschera, Daniela, additional, Sobolev, Anatoly Petrovich, additional, Beverina, Luca, additional, Calascibetta, Adiel Mauro, additional, Sanzone, Alessandro, additional, Di Carlo, Aldo, additional, Berionni Berna, Beatrice, additional, Pescetelli, Sara, additional, and Agresti, Antonio, additional

Published
2020
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35. Ab Initio Simulations of Interfaces between SAM-Modified Gold Electrodes and n-Type or p-Type Organic Semiconductors Based on the Benzothieno-Benzothiophene (BTBT) Architecture

Author

Mattioli, G, Mattiello, S, Sassi, M, Beverina, L, Mattioli, Giuseppe, Mattiello, Sara, Sassi, Mauro, Beverina, Luca, Mattioli, G, Mattiello, S, Sassi, M, Beverina, L, Mattioli, Giuseppe, Mattiello, Sara, Sassi, Mauro, and Beverina, Luca

Abstract

We have investigated the atomistic structure and the electronic properties of selected metal-organic interfaces, commonly found in organic electronic devices, using ab initio simulations based on density functional theory. Our study focuses, in particular, on the interaction of a widely used p-type organic semiconductor (OS) like the [1]benzothieno[3,2-b][1]-benzothiophene (BTBT) polycyclic molecule with a gold electrode, bare or functionalized with a self-assembled monolayer (SAM) of aromatic thiol used as a surface modifier. A similar investigation involved an S,S'-tetraoxide derivative of BTBT indicated as BTBTOx2, showing promising characteristics as an n-type semiconductor, whose original synthetic protocol is also discussed. First, our simulations, including the ab initio calculation of dispersion forces that permits an accurate description of noncovalent interactions, show that minimal changes in local interactions can induce a different arrangement of the same molecules in contact with metal electrodes. In particular, we report a stronger adhesion of BTBT and BTBTOx2 on bare gold, with the molecules lying flat on the surface, and a stronger cohesion of the same organic adlayers on gold surfaces functionalized with an SAM, with the molecules that prefer to form stacks parallel to the surface, more similar to those observed in the corresponding molecular crystals. Moreover, the functionalization of the same gold surface with self-assembled molecular modifiers having different polarities induces changes in the electronic properties of the Au/BTBT and Au/BTBTOx2 interfaces, transforming the Schottky junctions formed when the molecules are in direct contact with the bare gold surface in more favorable Au/SAM/OS junctions characterized by a significant reduction of the injection barrier or even a nearly Ohmic contact when the SAM is applied, in both the p-type and n-type investigated cases.

Published
2020

36. Selective Effects of the Host Matrix in Hydrogenated InGaAsN Alloys: Toward an Integrated Matrix/Defect Engineering Paradigm.

Author

Filippone, Francesco, Younis, Saeed, Mattioli, Giuseppe, Felici, Marco, Blundo, Elena, Polimeni, Antonio, Pettinari, Giorgio, Giubertoni, Damiano, Sterzer, Eduard, Volz, Kerstin, Fekete, Dan, Kapon, Eli, and Amore Bonapasta, Aldo

Subjects
MATRIX effect, DILUTE alloys, ALLOYS, DENSITY functional theory, PHOTOLUMINESCENCE measurement, HYDROGEN atom
Abstract

In dilute nitride InyGa1−yAs1−xNx alloys, a spatially controlled tuning of the energy gap can be realized by combining the introduction of N atoms—inducing a significant reduction of this parameter—with that of hydrogen atoms, which neutralize the effect of N. In these alloys, hydrogen forms N–H complexes in both Ga‐rich and In‐rich N environments. Here, photoluminescence measurements and thermal annealing treatments show that, surprisingly, N neutralization by H is significantly inhibited when the number of In‐N bonds increases. Density functional theory calculations account for this result and reveal an original, physical phenomenon: only in the In‐rich N environment, the InyGa1−yAs host matrix exerts a selective action on the N–H complexes by hindering the formation of the complexes more effective in the N passivation. This thoroughly overturns the usual perspective of defect‐engineering by proposing a novel paradigm where a major role pertains to the defect‐surrounding matrix. [ABSTRACT FROM AUTHOR]

Published
2022
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38. Unexpected Rotamerism at the Origin of a Chessboard Supramolecular Assembly of Ruthenium Phthalocyanine

Author

Mattioli Giuseppe, Larciprete Rosanna, Alippi Paola, Amore Bonapasta Aldo, Filippone Francesco, Lacovig Paolo, Lizzit Silvano, Paoletti Anna Maria, Pennesi Giovanna, Ronci Fabio, ZanottiGloria, Colonna, and Stefano.

Subjects
Photoemission spectroscopy, Ab initio, scanning probe microscopy, 02 engineering and technology, 010402 general chemistry, Photochemistry, 01 natural sciences, Catalysis, law.invention, Supramolecular assembly, chemistry.chemical_compound, Scanning probe microscopy, law, Microscopy, Scanning Tunneling, ab initio simulations, Organometallic Compounds, Molecule, Conformational isomerism, organic electronic devices, photoemission spectroscopy, Chemistry, Photoelectron Spectroscopy, Organic Chemistry, General Chemistry, 021001 nanoscience & nanotechnology, 0104 chemical sciences, Crystallography, ruthenium metal-organic molecules, Phthalocyanine, Quantum Theory, Scanning tunneling microscope, 0210 nano-technology
Abstract

We have investigated the formation and the prop- erties of ultrathin films of ruthenium phthalocyanine (RuPc) 2 vacuum deposited on graphite by scanning tunneling mi- croscopy and synchrotron photoemission spectroscopy measurements, interpreted in close conjunction with ab initio simulations. Thanks to its unique dimeric structure connected by a direct Ru?Ru bond, (RuPc) 2 can be found in two stable rotameric forms separated by a low-energy barri- er. Such isomerism leads to a peculiar organization of the molecules in flat, horizontal layers on the graphite surface, characterized by a chessboard-like alternation of the two ro- tamers. Moreover, the molecules are vertically connected to form p-stacked columnar pillars of akin rotamers, compatible with the high conductivity measured in (RuPc) 2 powders. Such features yield an unprecedented supramolecular as- sembly of phthalocyanine films, which could open interest- ing perspectives toward the realization of new architectures of organic electronic devices.

Published
2017
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41. Suzuki-Miyaura Micellar One-Pot Synthesis of Symmetrical and Unsymmetrical 4,7-Diaryl-5,6-difluoro-2,1,3-benzothiadiazole Luminescent Derivatives in Water and under Air

Author

Sanzone, A, Calascibetta, A, Ghiglietti, E, Ceriani, C, Mattioli, G, Mattiello, S, Sassi, M, Beverina, L, Sanzone, Alessandro, CALASCIBETTA, ADIEL MAURO, Ghiglietti, Erika, CERIANI, CHIARA, Mattioli, Giuseppe, Mattiello, Sara, Sassi, Mauro, Beverina, Luca, Sanzone, A, Calascibetta, A, Ghiglietti, E, Ceriani, C, Mattioli, G, Mattiello, S, Sassi, M, Beverina, L, Sanzone, Alessandro, CALASCIBETTA, ADIEL MAURO, Ghiglietti, Erika, CERIANI, CHIARA, Mattioli, Giuseppe, Mattiello, Sara, Sassi, Mauro, and Beverina, Luca

Abstract

The Suzuki-Miyaura cross-coupling reaction of 4,7-dibromo-5,6-difluoro-2,1,3-benzothiadiazole with different arylboronic acids can be efficiently carried out in water and under air by means of micellar coupling. The careful tuning of reaction conditions enables preparation of symmetrically and unsymmetrically substituted derivatives. The moderate to good yields obtained, along with the wide variety of available substitution patterns, makes this sustainable methodology very useful for the preparation of building blocks for luminescent optoelectronic materials

Published
2018

43. Unexpected Rotamerism at the Origin of a Chessboard Supramolecular Assembly of Ruthenium Phthalocyanine

Author

Mattioli, Giuseppe, primary, Larciprete, Rosanna, additional, Alippi, Paola, additional, Bonapasta, Aldo Amore, additional, Filippone, Francesco, additional, Lacovig, Paolo, additional, Lizzit, Silvano, additional, Paoletti, Anna Maria, additional, Pennesi, Giovanna, additional, Ronci, Fabio, additional, Zanotti, Gloria, additional, and Colonna, Stefano, additional

Published
2017
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44. A Ru-Ru pair housed in ruthenium phthalocyanine : the role of a 'cage' architecture in the molecule coupling with the Ag(111) surface

Author

Alippi, Paola, Lanzilotto, Valeria, Paoletti, Anna Maria, Mattioli, Giuseppe, Zanotti, Gloria, Pennesi, Giovanna, Filippone, Francesco, Cossaro, Albano, Verdini, Alberto, Morgante, Alberto, Bonapasta, Aldo Amore, Alippi, Paola, Lanzilotto, Valeria, Paoletti, Anna Maria, Mattioli, Giuseppe, Zanotti, Gloria, Pennesi, Giovanna, Filippone, Francesco, Cossaro, Albano, Verdini, Alberto, Morgante, Alberto, and Bonapasta, Aldo Amore

Abstract

A number of studies have investigated the properties of monomeric and double-decker phthalocyanines (Pcs) adsorbed on metal surfaces, in view of applications in spintronics devices. In a combined experimental and theoretical study, we consider here a different member of the Pcs family, the (RuPc)(2) dimer, whose structure is characterized by two paired up magnetic centers embedded in a double-decker architecture. For (RuPc)(2) on Ag(111), we show that this architecture works as a preserving cage by shielding the Ru-Ru pair from a direct interaction with the surface atoms. In fact, while noticeable surface-to-molecule charge transfer occurs with the ensuing quenching of the molecular magnetic moment, such phenomena occur here in the absence of a direct Ru-Ag coupling or structural rearrangement, at variance with other Pcs and thanks to the above shielding effect. These unique properties of the (RuPc)(2) architecture are expected to permit an easy control of the surface-to-molecule charge-transfer process as well as of the molecular magnetic properties, thus making the (RuPc)(2) dimer a significant paradigm for innovative "cage" structures as well as a promising candidate for applications in spintronics nano or single-molecule devices.

Published
2017
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45. A Ru–Ru pair housed in ruthenium phthalocyanine: the role of a “cage” architecture in the molecule coupling with the Ag(111) surface

Author

Alippi, Paola, primary, Lanzilotto, Valeria, additional, Paoletti, Anna Maria, additional, Mattioli, Giuseppe, additional, Zanotti, Gloria, additional, Pennesi, Giovanna, additional, Filippone, Francesco, additional, Cossaro, Albano, additional, Verdini, Alberto, additional, Morgante, Alberto, additional, and Amore Bonapasta, Aldo, additional

Published
2017
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50. A Spotlight on the Compatibility between XFEL and Ab Initio Structures of the Oxygen Evolving Complex in Photosystem II.

Author

Narzi, Daniele, Mattioli, Giuseppe, Bovi, Daniele, and Guidoni, Leonardo

Subjects
*OXYGEN compounds, *CHEMICALS, *PHOTOSYSTEMS, *NONMETALS, *CHALCOGENS
Abstract

The Mn4CaO5 cluster of photosystem II promotes a crucial step in the oxygenic photosynthesis, namely, the water-splitting reaction. The structure of such cluster in the S1 state of the Kok-Joliot's cycle has been recently resolved by femtosecond X-ray free-electron laser (XFEL) measurements. However, the XFEL results are characterized by appreciable discrepancies with previous X-ray diffraction (XRD), as well as with S1 models based on ab initio calculations. We provide here a unifying picture based on a combined set of DFT-based structures and molecular dynamics simulations of the S0 and S1 states. Our findings indicate that the XFEL results cannot be interpreted on the grounds of a single structure. A combination of two S1 stable isomers together with a minority contribution of the S0 state is necessary to reproduce XFEL results within 0.16 Å. [ABSTRACT FROM AUTHOR]

Published
2017
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