5,142 research outputs found
Contro la funzionalizzazione della contrattazione collettiva. Riflessioni sul pensiero di Mario Rusciano
No full textL'autore riflette sul pensiero di Mario Rusciano in punto di funzionalizzazione della contrattazione collettiva.The author reflects on the thought of Mario Rusciano in relation to the subject of the functionalisation of collective bargaining
DoNOF: An open-source implementation of natural-orbital-functional-based methods for quantum chemistry
No full textThe natural orbital functional theory (NOFT) has emerged as an alternative formalism to both density functional (DF) and wavefunction methods. In NOFT, the electronic structure is described in terms of the natural orbitals (NOs) and their occupation numbers (ONs). The approximate NOFs have proven to be more accurate than those of the density for systems with a significant multiconfigurational character, on one side, and scale better with the number of basis functions than correlated wavefunction methods, on the other side. A challenging task in NOFT is to efficiently perform orbital optimization. In this article we present DoNOF, our open source implementation based on diagonalizations that allows to obtain the resulting orbitals automatically orthogonal. The one-particle reduced-density matrix (1RDM) of the ensemble of pure-spin states provides the proper description of spin multiplets. The capabilities of the code are tested on the water molecule, namely, geometry optimization, natural and canonical representations of molecular orbitals, ionization potential, and electric moments. In DoNOF, the electron-pair-based NOFs developed in our group PNOF5, PNOF7 and PNOF7s are implemented. These JKL-only NOFs take into account most non-dynamic effects plus intrapair-dynamic electron correlation, but lack a significant part of interpair-dynamic correlation. Correlation corrections are estimated by the single-reference NOF-MP2 method that simultaneously calculates static and dynamic electron correlations taking as a reference the Slater determinant formed with the NOs of a previous PNOF calculation. The NOF-MP2 method is used to analyze the potential energy surface (PES) and the binding energy for the symmetric dissociation of the water molecule, and compare it with accurate wavefunction-based methods
Il diritto penale nel canone di Mario Romano
No full textThis paper deals with the extension and the extraordinary scientific value of the works written by a great Master in Criminal Law, such as Mario Romano. The Author briefly presents some of the most relevant contributions given by Professor Mario Romano to the Criminal Science, first of all his "Commentario sistematico del codice penale" (Systematic Commentary on the penal code), a unique work. Finally, the paper talks about some topics which have been developed inside the work "Studi in onore di Mario Romano" (Studies in Honour of Mario Romano)
Excited states by coupling Piris natural orbital functionals with extended random phase approximation
No full textIn this work, we extend the Piris natural orbital functionals (PNOFs) to
excited states by coupling their reconstructed second-order reduced density
matrices with the extended random-phase approximation (ERPA). We have named the
general implementation as PNOF-ERPA, and we refer to specific cases as
PNOF-ERPA0, PNOF-ERPA1 and PNOF-ERPA2, according to how the excitation operator
is built. The approaches have been tested in the first excited states of H2,
HeH+, LiH and Li2, showing good results compared with the full configuration
interaction (FCI) method. As expected, an increase in accuracy is observed when
going from ERPA0 to ERPA1 and ERPA2. We have also studied the effect of
electron correlation included by PNOF5, PNOF7 and the recently proposed global
NOF (GNOF) on the predicted excited states. PNOF5 appears to be good and may
even provide better results in very small systems, but including more electron
correlation becomes important as the system size increases, where PNOF7 and
GNOF provide better results. This effect can already be seen in the excitation
energies of the neon atom, where GNOF provides more accurate values than PNOF5
and PNOF7. Overall, the extension of PNOF to excited states has been
successful, making the PNOF-ERPA method promising for further applications.Comment: 18 pages, 10 figure
Molecular electric moments calculated by using natural orbital functional theory
No full textThe molecular electric dipole, quadrupole and octupole moments of a selected set of 21 spin-compensated molecules are determined employing the extended version of the Piris natural orbital functional 6 (PNOF6), using the triple-zeta Gaussian basis set with polarization functions developed by Sadlej, at the experimental geometries. The performance of the PNOF6 is established by carrying out a statistical analysis of the mean absolute errors with respect to the experiment. The calculated PNOF6 electric moments agree satisfactorily with the corresponding experimental data, and are in good agreement with the values obtained by accurate ab initio methods, namely, the coupled-cluster single and doubles (CCSD) and multi-reference single and double excitation configuration interaction (MRSD-CI) methods
Excited States by Coupling Piris Natural Orbital Functionals with the Extended Random-Phase Approximation
No full textIn this work, we
explore the use of Piris natural orbital functionals
(PNOFs) to calculate excited-state energies by coupling their reconstructed
second-order reduced density matrix with the extended random-phase
approximation (ERPA). We have named the general method PNOF-ERPA,
and specific approaches are referred to as PNOF-ERPA0, PNOF-ERPA1,
and PNOF-ERPA2, according to the way the excitation operator is built.
The implementation has been tested in the first excited states of
H2, HeH+, LiH, Li2, and N2 showing good results compared to the configuration interaction (CI)
method. As expected, an increase in accuracy is observed on going
from ERPA0 to ERPA1 and ERPA2. We also studied the effect of electron
correlation included by PNOF5, PNOF7, and the recently proposed global
NOF (GNOF) on the predicted excited states. PNOF5 appears to be good
and may even provide better results in very small systems, but including
more electron correlation becomes important as the system size increases,
where GNOF achieves better results. Overall, the extension of PNOF
to excited states has been successful, making it a promising method
for further applications
Introduzione, a Mario Tobino, Il Clandestino
No full textL'introduzione presenta il libro più ambizioso di Mario Tobino, Il Clandestino, dedicato al racconto della sua esperienza con i gruppi clandestini della Resistenza Viareggina, libro con cui l'autore vinse il Premio Strega, nel 1962, imponendosi all'attenzione del grande pubblico dopo il successo dei libri manicomiali. Una nuova edizione in cui Paola Italia valorizza i materiali inediti dell'Archivio Tobino conservato presso l'Archivio Contemporaneo A. Bonsanti del Gabinetto GP Vieusseux di Firenze,Paola Italia presents an Introduction to the new edtion of Il Clandestino, the most ambitious of Mario Tobino's novels, dedicated to the story of his experience with the groups of the Tuscan Resistance when he was a psichiatric doctor ar Lucca. With this book the author won the Strega Prize, in 1962, attracting the attention of a wide public after the success of his psichiatric books. A new edition where Paola Italia enhances the unpublished material of Tobino Archive preserved in A. Bonsanti Contemporary Archive of G.P. Vieusseux Cabinet of Florence
L'uno e il molteplice: su Catull. 5
No full textIn Catull. 5, the author cleverly works out two ancient topoi (‘let’s love, because the night/death is coming’; ‘kisses are the joy of lovers’), gaining a well balanced structure of the poem. In comparison with contemporary Graeco-Roman poetry (erotic epigrams – such as Philod. AP 9, 570 –, the Epitaph of Bion), both themes are handled with a remarkable taste for originality, especially in their ‘numerical’ aspects, in order to put special emphasis on the basic contrast between nox una and basia mille
In memoriam Mario Napoli
No full textL'autore ricorda la vita e le principali opere di Mario Napoli, suo Maestro e illustre studioso del Diritto italiano del lavoro.The author remembers the life and the most important works of Mario Napoli, his Master and one of the leading scholars of Italian labour law
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