Carlo Corvaja

Bio: Carlo Corvaja is an academic researcher from University of Padua. The author has contributed to research in topics: Electron paramagnetic resonance & Excited state. The author has an hindex of 23, co-authored 163 publications receiving 2464 citations. Previous affiliations of Carlo Corvaja include University of Trieste & University of Camerino.

EPR Investigation of Photoinduced Radical Pair Formation and Decay to a Triplet State in a Carotene−Porphyrin−Fullerene Triad

Abstract: The photochemistry of a molecular triad consisting of a porphyrin (P) covalently linked to a carotenoid polyene (C) and a fullerene derivative (C60) has been studied at 20 K by time-resolved EPR sp...

One-dimensional and two-dimensional coordination polymers from self-assembling of trinuclear triangular Cu(II) secondary building units

Abstract: The reactions of pyrazole (Hpz) with some copper(II) carboxylates in the presence of water yield trinuclear copper derivatives characterized by the triangular core [Cu3(μ3-OH)(μ-pz)3(RCOO)2] (R = H, C2H5, C3H7). Copper(II) formate gives [Cu3(μ3-OH)(μ-pz)3(HCOO)2(Hpz)2] (1), whereas copper propionate and butyrate afford [Cu3(μ3-OH)(μ-pz)3(C2H5COO)2(EtOH)] (2) and [Cu3(μ3-OH)(μ-pz)3(C3H7COO)2(MeOH)(H2O)] (3), respectively, both containing solvent molecules coordinated to copper atoms. Magnetic susceptibilities are consistent with a single unpaired electron for each trinuclear unit of 1−3, and EPR measurements indicate that higher spin states, generated by exchange coupling between copper atoms, may be populated at room temperature. Density-functional calculations provide the description of the electronic structures of 1−3, allowing, at the same time, the assignment of their UV−vis absorption spectra. X-ray molecular structure determinations show that triangular trinuclear units of 1 are connected to each ot...

Spontaneous Self-Assembly of an Unsymmetric Trinuclear Triangular Copper(II) Pyrazolate Complex, [Cu3(μ3-OH)(μ-pz)3(MeCOO)2(Hpz)] (Hpz = Pyrazole). Synthesis, Experimental and Theoretical Characterization, Reactivity, and Catalytic Activity

Abstract: The almost quantitative formation of the triangular trinuclear copper derivative [Cu3(μ3-OH)(μ-pz)3(MeCOO)2(Hpz)] (1) (Hpz = pyrazole), has been simply achieved by adding Hpz to an ethanol solution of Cu(MeCOO)2·H2O. An X-ray molecular structure determination shows that 1 is completely unsymmetric and that trinuclear units result assembled in an extended bidimensional network formed through acetate bridges and hydrogen bonds. EPR and magnetic measurements are consistent with the presence of a single unpaired electron. Theoretical density functional calculations carried out for S = 1/2 provide a thorough description of the electronic structure of 1, allowing a detailed assignment of its UV−vis absorption spectrum. Compound 1 reacts with MeONa, yielding [Cu3(μ3-OH)(μ-pz)3(MeCOO)(MeO)(Hpz)] (2) and [Cu3(μ3-OH)(μ-pz)3(MeO)2(Hpz)] (3) through the substitution of one and two acetate ions, respectively, with MeO- ion(s). The spontaneous self-assembly of the triangular trinuclear Cu3 moiety seems to occur only wi...

Synthesis and conformational studies of peptides containing TOAC, a spin-labelled Cα,α-disubstituted glycine

Abstract: A variety of host L-alanine homo-peptides (to the pentamer) containing one or two spin-labelled TOAC (2,2,6,6-tetramethylpiperidine-1-oxyl-4-amino-4-carboxylic acid) residues were synthesized by solution methods and fully characterized. The conformational features of the terminally blocked, doubly spin-labelled TOAC-(Ala)2-TOAC-Ala-pentapeptide were examined in the crystal state by X-ray diffraction and in solution using a combination of techniques (Fourier transform infrared, circular dichroism, cyclic voltammetry and electron spin resonance) in comparison with singly labelled shorter peptides. The 3(10)-helical structure of the pentapeptide, promoted by the two C alpha, alpha-disubstituted glycines under favourable experimental conditions, allows an interaction to take place between the two nitroxide TOAC side chains spaced by one turn of the helix. Taken together, these results suggest that TOAC is an excellent probe for exploring bends and helices in doubly labelled peptides.

The NOX Family of ROS-Generating NADPH Oxidases: Physiology and Pathophysiology

Abstract: For a long time, superoxide generation by an NADPH oxidase was considered as an oddity only found in professional phagocytes. Over the last years, six homologs of the cytochrome subunit of the phag...

Organic solar cells: An overview

Abstract: Organic solar cell research has developed during the past 30 years, but especially in the last decade it has attracted scientific and economic interest triggered by a rapid increase in power conversion efficiencies. This was achieved by the introduction of new materials, improved materials engineering, and more sophisticated device structures. Today, solar power conversion efficiencies in excess of 3% have been accomplished with several device concepts. Though efficiencies of these thin-film organicdevices have not yet reached those of their inorganic counterparts (η ≈ 10–20%); the perspective of cheap production (employing, e.g., roll-to-roll processes) drives the development of organic photovoltaic devices further in a dynamic way. The two competitive production techniques used today are either wet solution processing or dry thermal evaporation of the organic constituents. The field of organic solar cells profited well from the development of light-emitting diodes based on similar technologies, which have entered the market recently. We review here the current status of the field of organic solar cells and discuss different production technologies as well as study the important parameters to improve their performance.

Mimicking photosynthetic solar energy transduction

Abstract: Increased understanding of photosynthetic energy conversion and advances in chemical synthesis and instrumentation have made it possible to create artificial nanoscale devices and semibiological hybrids that carry out many of the functions of the natural process. Artificial light-harvesting antennas can be synthesized and linked to artificial reaction centers that convert excitation energy to chemical potential in the form of long-lived charge separation. Artificial reaction centers can form the basis for molecular-level optoelectronic devices. In addition, they may be incorporated into the lipid bilayer membranes of artificial vesicles, where they function as components of light-driven proton pumps that generate transmembrane proton motive force. The proton gradient may be used to synthesize adenosine triphosphate via an ATP synthase enzyme. The overall energy transduction process in the liposomal system mimics the solar energy conversion system of a photosynthetic bacterium. The results of this research illustrate the advantages of designing functional nanoscale devices based on biological paradigms.

Current progress on the chemical modification of carbon nanotubes.

Abstract: 2.3. Ionic Liquids (ILs) 5374 2.4. Complexation Reactions on Oxidized CNTs 5375 2.5. Halogenation 5376 2.6. Cycloaddition Reactions 5377 2.7. Radical Additions 5379 2.8. Nucleophilic Additions 5381 2.9. Electrophilic Additions 5381 2.10. Electrochemical Modifications 5381 2.11. Plasma-Activation 5381 2.12. Mechanochemical Functionalizations 5382 3. Noncovalent Interactions 5382 3.1. Polynuclear Aromatic Compounds 5382 3.2. Interactions with Other Substances 5384 3.3. Interactions with Biomolecules 5385 4. Endohedral Filling 5386 4.1. Encapsulation of Fullerenes 5386 4.2. Encapsulation of Organic Substances 5387 4.3. Encapsulation of Inorganic Substances 5387 5. Decoration of CNTs with Metal Nanoparticles 5388 5.1. Covalent Linkage 5388 5.2. Direct Formation on Defect Sites 5388 5.3. Electroless Deposition 5388 5.4. Electrodeposition 5389 5.5. Chemical Decoration 5390 5.6. Deposition of Nanoparticles onto CNTs 5391 5.7. π-π Stacking and Electrostatic Interactions 5391 6. Concluding Remarks 5392 7. Acknowledgments 5392 8. References 5392