28 results on '"Coccia, Emanuele"'
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2. ‘Regula et vita’. Il diritto monastico e la regola francescana
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Coccia, Emanuele
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diritto canonico ,Franciscanism ,Patristics ,monachesimo ,patristica ,regole monastiche ,diritto medievale ,Monasticism ,Francescanesimo ,Monastic Rules ,Canonic Law ,Medieval Law - Abstract
The article shows how the franciscan rule is a breaking off the previous monastic rules. To favour the coincidence between the rule and the life is really the specific characters of the franciscan reflection. The franciscan rule has as subject the observance of the Gospel and so this rule is as a legal purview. L’articolo evidenzia come la regola francescana costituisca una rottura con le precedenti regole monastiche. Proprio la radicalizzazione della coincidenza tra regula e vita connota la specificità della riflessione francescana. La regola francescana ha come contenuto l’osservanza del Vangelo e dunque tale regula vivendi si presenta come un dispositivo giuridico.
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- 2021
3. Une histoire au présent
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Bert, Jean-François, Boehringer, Sandra, Boquet, Damien, Boulnois, Olivier, Chevallier, Philippe, Claustre, Julie, Coccia, Emanuele, Cohen, Déborah, Dubouloz, Julien, Dufal, Blaise, Golsenne, Thomas, Guignard, Laurence, Halary, Marie-Pascale, Labey, Pauline, Ong-Van-Cung, Kim Sang, Paltrinieri, Luca, Senellart, Michel, Wahnich, Sophie, Boquet, Damien, Dufal, Blaise, and Labey, Pauline
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Philosophy ,HP ,philosophie ,folie ,raison ,gouvernementalité ,PHI000000 ,sexualité ,biopolitique - Abstract
Cette réflexion de Jacques Léonard doit être prise au sérieux. Cinquante ans après la parution de l’Histoire de la folie et alors que s’achève la publication des cours au Collège de France, le dialogue des historiens avec Michel Foucault se poursuit. Les textes réunis dans ce volume, abordant des périodes historiques différentes, mettent en avant des expériences individuelles au contact d’un Foucault désacralisé. Ils questionnent aussi bien des chantiers ouverts par Foucault (folie et déraison, enfermement psychiatrique et carcéral, pastorale, sexualité), des outils conceptuels (pratiques discursives, biopolitique, gouvernementalité, techniques de soi, régimes de vérité, objectivation du sujet), que des propositions historiographiques et épistémologiques (archéologie et généalogie, césure et continuité). Dans cette mise à l’épreuve, le passé devient un lieu de problématisation du présent, et l’histoire, une voie qui singularise l’actualité.
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- 2019
4. Potestas dicitur multipliciter
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Coccia, Emanuele
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Philosophy ,HP ,philosophie ,folie ,raison ,gouvernementalité ,PHI000000 ,sexualité ,biopolitique - Abstract
Le pouvoir dans tous ses états On a très souvent reproché à Michel Foucault de fournir des arguments pour ce qu’on a appelé la généralisation du soupçon du pouvoir (Generalisierung des Machtverdachtes) : « toute association, toute relation personnelle est maintenant soupçonnée de perpétuer des différences de pouvoir ou d’en couver de nouvelles. Le pouvoir se cache partout : il faut juste savoir le voir. […] Le pouvoir est censé être l’élément de toute socialisation. Le pouvoir est omniprésent...
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- 2019
5. Lifestyles: How to do Norms with Images
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Coccia, Emanuele
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Bild ,Werbung ,image ,iconography ,Ikonographie ,advertising - Published
- 2019
6. Adam, la nature humaine, avant et après
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Boulnois, Olivier, Boureau, Alain, Briguglia, Gianluca, Brilli, Elisa, Carron, Delphine, Casagrande, Carla, Coccia, Emanuele, Costa, Iacopo, Lambertini, Roberto, Piron, Sylvain, Robert, Aurélien, Rosier-Catach, Irène, Valente, Luisa, Vecchio, Silvana, Rosier-Catach, Irène, and Briguglia, Gianluca
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Philosophy ,péché originel ,HP ,chute de l’homme ,histoire des doctrines ,PHI000000 - Abstract
Que se serait-il passé si Adam n'avait pas péché ? Le récit de la Chute ne raconte pas seulement comment le premier homme et la première femme ont désobéi et ont été chassés du jardin de l'Éden. C'est aussi un instrument formidable pour penser philosophiquement la nature humaine, ses potentialités et ses limites, pour dessiner les différents plans d'une anthropologie complexe et diversifiée. La rupture du péché originel, qui instaure un Avant et un Après de la nature humaine, a représenté un défi intellectuel, une provocation pour la philosophie que la pensée médiévale - et moderne - a voulu recueillir et affronter. Cette nécessité s'est faite d'autant plus pressante que d'autres modèles anthropologiques devenaient disponibles, au premier rang desquels le modèle aristotélicien, où l'idée d'une rupture dans l'histoire humaine ou d'une naturalité scindée n'avait pas sa place. Les réflexions sur la Chute ont donné lieu à des débats importants sur le langage, la liberté et le mal, le bonheur, les passions, le corps, la vie et le pouvoir politique, le droit, le travail, qui sont l'objet des chapitres de ce livre. Prises ainsi dans leur dimension anthropologique, ces questions autour de la Chute deviennent un véritable modèle épistémologique pour penser la naturalité de l'homme et son histoire, en termes de dégradation ou de progrès, modèle qui dépasse l'époque médiévale et rejoint des questionnements que l'on retrouve notamment à l'âge classique.
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- 2019
7. La comédie du droit
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Coccia, Emanuele
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péché originel ,chute de l’homme ,histoire des doctrines - Abstract
Un homme sans qualités En 1893 sort la première version de ce qui reste la réécriture moderne la plus intéressante du mythe adamique. Dans ce Journal d’Adam, Mark Twain imaginait pouvoir recueillir et capturer les impressions et le vécu du premier regard qui s’est posé sur le monde et qui l’a observé d’un point de vue humain et non plus angélique ou divin. Et pourtant, les premiers commentaires de la première forme d’esprit humain sont loin d’être sublimes. « Cette nouvelle créature aux cheve...
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- 2019
8. Theoretical S1
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Coccia, Emanuele, Varsano, Daniele, and Guidoni, Leonardo
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Chemical Physics (physics.chem-ph) ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences - Abstract
The structures of three negatively charged forms (anionic keto-1 and enol-1, dianonic enol-2) of oxyluciferin (OxyLuc), which are the most probable emitters responsible for the firefly bioluminescence, have been fully relaxed at the variational Monte Carlo (VMC) level. Absorption energies of the S1, This document is the Accepted Manuscript version of a Published Work that appeared in final form in J. Chem. Theory Comput. copyright American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.jctc.7b00505
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- 2018
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9. Forms of Life:dis:positions | French Philosophy Today #2
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Coccia, Emanuele, Worms, Frédéric, and Zanfi, Caterina
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Life forces thought, it poses problems and constitutes, for philosophy, both a condition and an object. Whether framed through questions of epistemology and the philosophy of science, questions of ethics, of politics, of technics, of aesthetics or of metaphysics, conceptions of life and the living, while inherently and invariably transdisciplinary, remain at the core of philosophical thinking today. Accordingly, this second session in the series dis:positions gathers three protagonists of a moment du vivant within contemporary French philosophy, provoking a resolutely undisciplined conversation, a modulation of philosophy across all domains of knowledge. The legacy of the twentieth century weighs heavy on French philosophy. While the names of the stars of the years now regarded as those of rampant reading and writing still appear omnipresent, younger voices, at least on this side of the Rhine, are heard sporadically at best. But what escapes the view that attaches itself exclusively to the old masters? And which new possibilities, on the other hand, offer themselves to thinking when it detaches itself a little from the habitual – confronting its own conditions, but always also transgressing them?The series dis:positions | French Philosophy Today has set itself the task of being a philosophical passeur, a smuggler who overcomes boundaries and offers a forum to thinkers currently less well-known in Germany. At the same time, however, as the series will also show, there is no such thing as French thought in general, no such thing as French philosophy in general; accordingly, the claim of the series does not exceed the attempt to spotlight certain ideas, without presumptuous ambitions of completeness or objectivity. dis:positions is nothing more, nothing less, than the effort to present, every month and through conversations in different venues across Berlin, some current positions and dispositions of thought.Emanuele Coccia Frédéric Worms Caterina Zanfi Emanuele Coccia is maître de conférences at the École des Hautes Études en Sciences Sociales (EHESS) in Paris. After working on the history of European normativity and on aesthetics, his current research focuses on conceptions of life on the one hand and on the ontological status and normative power of images on the other. Among his publications are La vie des plantes. Une métaphysique du mélange (2016), Le bien dans les choses (2013), La vie sensible (2010), the anthology Angeli: ebraismo, cristianesimo, islam, co-ed. with Giorgio Agamben (2009), and La trasparenza delle immagini. Averroè e l’averroismo (2005). Frédéric Worms is professor of contemporary philosophy and moral philosophy at the École normale supérieure in Paris, where he also serves as directeur-adjoint of Lettres et Sciences humaines and director of the Centre international d’étude de la philosophie française (CIEPFC). Moreover, he is a member of the Comité consultatif national d’éthique. A specialist in the thought of Henri Bergson and the history of philosophy, his recent work concerns questions of ethics and politics, focusing on issues of human rights, care, and violence, considered from the perspective of the living. Among his recent books are Les maladies chroniques de la démocratie (2017), Penser à quelqu‘un (2014), Revivre. Éprouver nos blessures et nos ressources (2012), La Philosophie en France au XXe siècle. Moments (2009), and Bergson ou les deux sens de la vie (2004). Caterina Zanfi is a fellow of the Alexander von Humboldt Foundation at Bergische Universität Wuppertal. She studies the anthropological and political implications of the philosophies of life in a transnational perspective (Germany, France, Italy). She is the author of Bergson et la philosophie allemande : 1907-1932 (2013) and Bergson, la tecnica, la guerra (2009) and recently co-edited trivium 25. Die Philosophische Anthropologie in der deutsch-französischen Debatte der Gegenwart (2017) and Das Leben im Menschen oder der Mensch im Leben? Deutsch-Französische Genealogien zwischen Anthropologie und Anti-Humanismus (2017).diffrakt | centre for theoretical periphery, in cooperation with the Institut Français, Francfort en français, and the ICI BerlinThe event, like all events at the ICI Berlin, is open to the public, free of charge. The audience is presumed to consent to a possible recording on the part of the ICI Berlin. If you would like to attend the event yet might require assistance, please contact Event Management. Forms of Life: dis:positions | French Philosophy Today #2, discussion, ICI Berlin, 20 June 2017
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- 2017
10. Time-Dependent Linear-Response Variational Monte Carlo
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Mussard, Bastien, Coccia, Emanuele, Assaraf, Roland, Otten, Matt, Umrigar, C. J., Toulouse, Julien, Mussard, B, Coccia, E, Assaraf, R, Otten, M, Umrigar, C J, Toulouse, J., Laboratoire de chimie théorique (LCT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Institut des Sciences du Calcul et des Données (ISCD), Université Pierre et Marie Curie - Paris 6 (UPMC)-Sorbonne Université (SU), Dipartimento di Scienze Fisiche e Chimiche [L'Aquila], Università degli Studi dell'Aquila (UNIVAQ), Laboratory of Atomic and Solid State Physics [Ithaca] (LASSP), Cornell University [New York], Université Pierre et Marie Curie - Paris 6 (UPMC), and Università degli Studi dell'Aquila = University of L'Aquila (UNIVAQ)
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Chemical Physics (physics.chem-ph) ,Physics::Computational Physics ,Tamm-Dancoff approximation ,GEMINAL POWER ,WAVE-FUNCTIONS ,EXCITATION ,MOLECULES ,oscillator strengths ,FOS: Physical sciences ,excitation energies ,Computational Physics (physics.comp-ph) ,beryllium ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,[PHYS.PHYS.PHYS-COMP-PH]Physics [physics]/Physics [physics]/Computational Physics [physics.comp-ph] ,linear method ,Physics - Chemical Physics ,[PHYS.PHYS.PHYS-CHEM-PH]Physics [physics]/Physics [physics]/Chemical Physics [physics.chem-ph] ,Physics - Computational Physics - Abstract
We present the extension of variational Monte Carlo (VMC) to the calculation of electronic excitation energies and oscillator strengths using time-dependent linear-response theory. By exploiting the analogy existing between the linear method for wave-function optimisation and the generalised eigenvalue equation of linear-response theory, we formulate the equations of linear-response VMC (LR-VMC). This LR-VMC approach involves the first-and second-order derivatives of the wave function with respect to the parameters. We perform first tests of the LR-VMC method within the Tamm-Dancoff approximation using single-determinant Jastrow-Slater wave functions with different Slater basis sets on some singlet and triplet excitations of the beryllium atom. Comparison with reference experimental data and with configuration-interaction-singles (CIS) results shows that LR-VMC generally outperforms CIS for excitation energies and is thus a promising approach for calculating electronic excited-state properties of atoms and molecules., Advances in Quantum Chemistry, 2017, Novel Electronic Structure Theory: General Innovations and Strongly Correlated Systems
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- 2017
11. Size dependent solvatation of p-H2 in 4He nanodroplets: A quantum Monte Carlo analysis
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COCCIA, EMANUELE, BODO, Enrico, GIANTURCO, Francesco Antonio, Coccia, Emanuele, Bodo, Enrico, and Gianturco, Francesco Antonio
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adsorbed layers ,drops ,helium ,hydrogen ,molecular clusters ,Monte Carlo methods ,reaction kinetics theory ,solvation ,variational ,cluster - Abstract
Variable-size He-4(N) clusters doped with a single p-H-2 molecule are studied here using variational and diffusion Monte Carlo calculations that show the highly quantum nature of the dopant and the solvent. Energetic and structural features extracted from our analysis reveal that the p-H-2 molecule behaves as a gentle perturber: The He droplets remain essentially liquidlike, with no evident structural change with respect to the pure ones. The p-H-2 dopant represents a kind of "competitor" for helium in the smaller droplets because it can replace the solvent adatoms; it also remains immersed in the cluster as N increases although located off-center within the droplet, while, finally, getting fully solvated in the larger droplets. The calculations are carried out up to N=100 as the largest number of solvent He-4 atoms and clearly show no evidence of either shell structuring or of "magic" numbers in the size of the smaller droplets.
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- 2009
12. ANIONIC MICROSOLVATION IN HELIUM DROPLETS: (OH-)(HE)N FROM CLASSICAL AND QUANTUM STRUCTURE CALCULATIONS
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COCCIA, EMANUELE, MARINETTI, FABIO, BODO, Enrico, GIANTURCO, Francesco Antonio, Coccia, Emanuele, Marinetti, Fabio, Bodo, Enrico, and Gianturco, Francesco Antonio
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monte carlo - Published
- 2008
13. Rezension: Valentina Toneatto / Peter Černic / Susi Paulitti: Economia monastica. Dalla disciplina del desiderio all’amministrazione razionale (rezensiert von Emanuele Coccia)
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Coccia, Emanuele
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- 2013
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14. Mente e matéria ou a vida das plantas
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Coccia, Emanuele
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Revista Landa, v. 1, n. 2 (2013)
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- 2013
15. L’anecdote sacrée
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Coccia, Emanuele
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- 2012
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16. Binding He atoms to hydrogen moieties: quantum features from ultraweak interactions
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Orlandini, S., Coccia, Emanuele, Baccarelli, Isabella, Gianturco, Francesco Antonio, Garrido, E., GONZALEZ LEZANA, T., Villareal, P., Orlandini, S., Coccia, E., Baccarelli, I., Gianturco, F., Garrido, E., GONZALEZ-LEZANA, T., and Villareal, P.
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- 2010
17. Poésie, sciences et politique. Une génération d'intellectuels italiens (1290-1330)
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Piron, Sylvain, Coccia, Emanuele, Groupe d'anthropologie scolastique/Equipe CRH (GAS-CRH), École des hautes études en sciences sociales (EHESS)-Centre National de la Recherche Scientifique (CNRS), Centre de Recherches Historiques (CRH), Philosophisches Seminar, University of Freiburg [Freiburg], and Piron, Sylvain
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Marsile de Padoue ,Italie ,poésie ,[SHS.HIST] Humanities and Social Sciences/History ,Albertino Mussato ,Cino da Pistoia ,philosophie ,droit ,Dante Alighieri ,Cecco d'Ascoli ,médecine ,[SHS.HIST]Humanities and Social Sciences/History ,politique - Abstract
International audience; Rien n'est plus faux que l'image de Dante comme génie isolé, tranchant sur son époque. Il appartient au contraire à une génération d'intellectuels italiens très caractéristique : laïcs, souvent curieux de plusieurs sciences, pratiquant abondamment la poésie, engagés dans l'action politique, ces savants-citoyens partagent également une forte conscience historique. Leur inventivité se manifeste en philosophie, en médecine et en droit, autant que dans l'expression littéraire. Outre des facteurs endogènes, une clé de ce phénomène tient à la réception active du savoir naturaliste élaboré à Paris, qui a été lu et assimilé en Italie hors du contrôle des théologiens. Les parcours parallèles d'une douzaine de personnalités actives sur plusieurs fronts montrent la nécessité d'élargir les cadres habituels de l'histoire intellectuelle médiévale.
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- 2008
18. Features of a spatially adaptive quantum solvent from stochastic calculations: neutral and ionic impurities in helium droplets
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Coccia, Emanuele, Bodo, Enrico, and Gianturco, Francesco Antonio
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- 2006
19. Intellectus sive intelligentia : Alberto Magno, Averroè e la noetica degli arabi
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Coccia, Emanuele
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- 2006
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20. Circularly Polarized Plasmons in Chiral Gold Nanowires via Quantum-Mechanical Design
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Alessandro Fortunelli, Andrea Russi, Giovanna Fronzoni, Daniele Toffoli, Emanuele Coccia, Luca Sementa, Mauro Stener, Toffoli, Daniele, Russi, Andrea, Fronzoni, Giovanna, Coccia, Emanuele, Stener, Mauro, Sementa, Luca, and Fortunelli, Alessandro
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Circular dichroism ,Nanowire ,Physics::Optics ,02 engineering and technology ,Electronic structure ,Metal clusters ,010402 general chemistry ,Dichroic glass ,01 natural sciences ,Molecular physics ,Circular Dichroism ,TDDFT ,plasmons ,General Materials Science ,Physical and Theoretical Chemistry ,Surface plasmon resonance ,Quantum ,Plasmon ,Physics ,Density functional theory ,Dichroism ,Gold ,Light polarization ,Plasmonics ,Quantum theory ,Time-dependent density functional theory ,Metal cluster ,021001 nanoscience & nanotechnology ,0104 chemical sciences ,0210 nano-technology - Abstract
Time-dependent density functional theory (TDDFT) simulations are conducted on a series of chiral gold nanowires to explore whether an enhancement of circular dichroism at the plasmon resonance is possible and identify its quantum-mechanical origin. We find that in linear two-dimensional chiral nanowires the dichroic response is suppressed by destructive interference of nearly degenerate components with opposite signs, pointing to this phenomenon as a common and likely origin of the difficulty encountered so far in achieving a plasmonic CD response in experiment and suggesting nevertheless that these opposite components could be "decoupled" by using multiwall arrangements. In contrast, we predict a giant dichroic response for nanowires with three-dimensional helical coiling. We rationalize this finding via an electronic structure analysis of longitudinal and transversal plasmonic excitations and their coupling into chiral components, and we propose a simple formula for the chiral response as a function of structural parameters (nanowire length and coiling number).
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- 2021
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21. Probing the molecular frame of uracil and thymine with high-harmonic generation spectroscopy
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Emanuele Coccia, Eleonora Luppi, Luppi, Eleonora, and Coccia, Emanuele
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Physics ,time propagation ,Spectrum Analysis ,General Physics and Astronomy ,Pulse duration ,Uracil ,Configuration interaction ,Molecular physics ,Spectral line ,Thymine ,chemistry.chemical_compound ,Models, Chemical ,chemistry ,Ionization ,Quantum Theory ,High harmonic generation ,Physical and Theoretical Chemistry ,Spectroscopy - Abstract
In this work, we present the computed high-harmonic generation (HHG) spectra of uracil and thymine molecules, by means of the real-time time-dependent formulation of Gaussian-based configuration interaction with single excitations (RT-TD-CIS). According to the experimental work [Hutchison et al., Comparison of high-order harmonic generation in uracil and thymine ablation plumes, Phys. Chem. Chem. Phys., 2013, 15, 12308], a pulse wavelength of 780 nm has been used, together with an intensity of 1014 W cm-2 and a pulse duration of 23 optical cycles. In order to examine the effect of pulse polarisation, rotationally averaged (to mimic the gas-phase sample) and single-polarisations have been computed for both molecules. Our results show that the HHG signal for both molecules possibly originates from different ionisation channels, involving HOMO, HOMO-1, HOMO-2 and HOMO-3 orbitals, which lie within 4 eV. We characterize the HHG spectrum of thymine, supporting the idea that the absence of the thymine signal in the original work does not depend on the single-molecule behaviour. Present results for uracil are consistent with the experimental data. Moreover, we have observed that states below and above the chosen ionisation threshold provide different contributions to the HHG spectrum in averaged and single-polarisation calculations.
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- 2021
22. Probing quantum coherence in ultrafast molecular processes: An ab initio approach to open quantum systems
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Stefano Corni, Filippo Troiani, Emanuele Coccia, Coccia, Emanuele, Troiani, Filippo, and Corni, Stefano
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Dephasing ,Ab initio ,General Physics and Astronomy ,FOS: Physical sciences ,02 engineering and technology ,01 natural sciences ,Schrödinger equation ,symbols.namesake ,Physics and Astronomy (all) ,Ab initio quantum chemistry methods ,Physics - Chemical Physics ,Quantum mechanics ,0103 physical sciences ,Physical and Theoretical Chemistry ,Wave function ,Quantum ,Physics ,Chemical Physics (physics.chem-ph) ,010304 chemical physics ,Time evolution ,021001 nanoscience & nanotechnology ,symbols ,0210 nano-technology ,Coherence (physics) - Abstract
Revealing possible long-living coherence in ultrafast processes allows detecting genuine quantum mechanical effects in molecules. To investigate such effects from a quantum chemistry perspective, we have developed a method for simulating the time evolution of molecular systems, based on ab initio calculations that includes relaxation and environment-induced dephasing of the molecular wave function, whose rates are external parameters. The proposed approach combines a quantum chemistry description of the molecular target with a real-time propagation scheme within the time-dependent stochastic Schroedinger equation. Moreover, it allows a quantitative characterization of the state and dynamics coherence, through the l1-norm of coherence and the linear entropy, respectively. To test the approach, we have simulated femtosecond pulse-shaping ultrafast spectroscopy of terrylenediimide, a well studied fluorophore in single-molecule spectroscopy. Our approach is able to reproduce the experimental findings [R. Hildner et al.,Nature Phys., 7, 172 (2011)], confirming the usefulness of the approach and the correctness of the implementation., Comment: This is the final version accepted for publication of a work that is appearing in Journal of Chemical Physics (Copyright AIP)
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- 2018
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23. Optimal-continuum and multicentered Gaussian basis sets for high-harmonic generation spectroscopy
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Emanuele Coccia, Eleonora Luppi, Laboratoire de chimie théorique (LCT), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), LabEx MiChem part of French state funds [ANR-11-IDEX-0004-02], Coccia, Emanuele, and Luppi, E
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Nonlinear optics ,Attosecond ,Gaussian ,Time-dependent configuration interaction ,Laser ,01 natural sciences ,symbols.namesake ,Quantum mechanics ,0103 physical sciences ,Physics::Atomic and Molecular Clusters ,High harmonic generation ,[CHIM]Chemical Sciences ,Physics::Atomic Physics ,Physical and Theoretical Chemistry ,010306 general physics ,Spectroscopy ,Basis set ,010304 chemical physics ,Chemistry ,Hydrogen atom ,Configuration interaction ,Computational physics ,Nonlinear optic ,symbols - Abstract
International audience; High-harmonic generation (HHG) is used to produce coherent XUV and soft X-ray radiation with attosecond resolution and is a sensitive tool for probing atomic and molecular structures. In this work, we have used time-dependent configuration interaction with a Gaussian basis set to compute the HHG spectrum of the hydrogen atom. To get a correct description of the HHG optical spectrum, the Gaussian basis set has to provide an accurate representation of the bound and the continuum states. Two strategies have been proposed: (1) multicentered (defining ghost atoms around the hydrogen) and (2) optimal-continuum Gaussian basis sets. We have systematically investigated these two approaches for the hydrogen atom, which permits a non-biased analysis of the basis set. Several basis sets have been constructed and tested by combining multicentered and optimal-continuum functions together in order to obtain a reliable and accurate Gaussian basis set to be used for HHG. We have studied the effect of changing the number of ghost atoms and the distance between the ghosts and the hydrogen atom, with and without optimal-continuum Gaussian functions. We conclude that multicentered basis sets are less efficient than basis sets using only optimal-continuum Gaussian functions for a proper description of HHG.
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- 2016
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24. Role of Electron Correlation along the Water Splitting Reaction
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Leonardo Guidoni, Emanuele Coccia, Shi-Bing Chu, Matteo Barborini, Chu, Shibing, Coccia, Emanuele, Barborini, Matteo, and Guidoni, Leonardo
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Quantum Monte Carlo ,010402 general chemistry ,OXIDATION ,01 natural sciences ,Molecular physics ,Atomic orbital ,SYSTEMS ,0103 physical sciences ,QUANTUM MONTE-CARLO ,Physical and Theoretical Chemistry ,Wave function ,CATALYST ,010304 chemical physics ,Electronic correlation ,Chemistry ,Computer Science Applications1707 Computer Vision and Pattern Recognition ,STATES ,BOND ,0104 chemical sciences ,Computer Science Applications ,Slater determinant ,Water splitting ,Diffusion Monte Carlo ,Density functional theory ,Atomic physics - Abstract
Electron correlation plays a crucial role in the energetics of reactions catalyzed by transition metal complexes, such as water splitting. In the present work we exploit the performance of various methods to describe the thermodynamics of a simple but representative model of water splitting reaction, based on a single cobalt ion as catalyst. Density Functional Theory (DFT) calculations show a significant dependence on the adopted functional, and not negligible differences with respect to CCSD(T) findings are found along the reaction cycle. We performed quantum Monte Carlo calculations using an unrestricted single Slater determinant wave function multiplied by a Jastrow factor using both DFT and fully optimized orbitals. Variational and Lattice Regularized Diffusion Monte Carlo results are in overall agreement with the CCSD(T) free-energy profile, even though differences in the description of the thermodynamics of the reaction cycle are found. NEVPT2 calculations reveal that the role of the static correlation of the different reaction steps is not large, and it is limited to only a few intermediate structures. Finally, the free-energy difference of the overall water splitting reaction computed at the quantum Monte Carlo level shows an excellent match with the experimental value of 4.92 eV, underlining the capability of these techniques to properly describe the dynamical correlation of such reactions.
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- 2016
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25. Spin-driven structural effects in alkali doped He-4 clusters from quantum calculations
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Stefano Bovino, Enrico Bodo, Emanuele Coccia, F. A. Gianturco, D. López-Durán, Bovino, Stefano, Coccia, Emanuele, Bodo, Enrico, LOPEZ DURAN, D, and Gianturco, Francesco Antonio
- Subjects
Chemistry ,Quantum mechanics ,Quantum Monte Carlo ,Monte Carlo method ,Dynamic Monte Carlo method ,General Physics and Astronomy ,Diffusion Monte Carlo ,Variational Monte Carlo ,Singlet state ,Physical and Theoretical Chemistry ,Triplet state ,Molecular physics ,Spin-½ - Abstract
In this paper, we carry out variational Monte Carlo and diffusion Monte Carlo (DMC) calculations for Li(2)((1)Sigma(g) (+))((4)He)(N) and Li(2)((3)Sigma(u) (+))((4)He)(N) with N up to 30 and discuss in detail the results of our computations. After a comparison between our DMC energies with the "exact" discrete variable representation values for the species with one (4)He, in order to test the quality of our computations at 0 K, we analyze the structural features of the whole range of doped clusters. We find that both species reside on the droplet surface, but that their orientation is spin driven, i.e., the singlet molecule is perpendicular and the triplet one is parallel to the droplet's surface. We have also computed quantum vibrational relaxation rates for both dimers in collision with a single (4)He and we find them to differ by orders of magnitude at the estimated surface temperature. Our results therefore confirm the findings from a great number of experimental data present in the current literature and provide one of the first attempts at giving an accurate, fully quantum picture for the nanoscopic properties of alkali dimers in (4)He clusters.
- Published
- 2009
26. Chemical solutions in a quantum solvent: anionic 'electrolytes' in 4He nanodroplets
- Author
-
Emanuele Coccia, Enrico Bodo, F. A. Gianturco, F. Marinetti, Coccia, Emanuele, Marinetti, Fabio, Bodo, Enrico, and Gianturco, Francesco Antonio
- Subjects
Chemistry ,Ab initio ,Electrolyte ,Alkali metal ,Helium ,Atomic and Molecular Physics, and Optics ,Monte Carlo simulations ,Solvent ,halides ,Delocalized electron ,Ab initio calculations ,cluster compounds ,Physical chemistry ,Quantum solvent ,Diffusion Monte Carlo ,Physical and Theoretical Chemistry ,Wave function ,cluster - Abstract
Variational and diffusion Monte Carlo (VMC and DMC) calculations are presented for anionic electrolytes solvated in (4)He. The electrolytes have the general structure X(-)(He)(N), with X=F, Cl, Br and I, and N varying up to 40 (41 for I(-)). The overall interaction potential is obtained from accurate ab initio data for the two-body components and then using the sum-of-potentials approximation. Our computational scheme is a robust procedure, giving us accurate trial wavefunctions that can be used to perform high-quality DMC calculations. The results indicate very marked delocalization and permanence of the liquid-like quantum features of the solvent adatoms surrounding the anionic impurities. This finding stands in contrast to the more structured, solid-like behavior of the quantum solutions with alkali metal cations embedded in He nanodroplets. While other negatively charged species such as H(-) have shown an overall repulsive interaction with He, the present calculations clearly indicate that the halogen anions remain solvated within liquid-like solvent "bubbles" of species-dependent size.
- Published
- 2008
27. Microsolvation of cationic dimers in 4He droplets: geometries of A2+(He) N (A=Li,Na,K) from optimized energies
- Author
-
Marinetti, F., Uranga-Piña, Ll., Coccia, E., López-Durán, D., Bodo, E., Gianturco, F. A., Marinetti, Fabio, URANGA PINA, L. L., Coccia, Emanuele, D., LOPEZ DURAN, Bodo, Enrico, and Gianturco, Francesco Antonio
- Subjects
Chemical Physics (physics.chem-ph) ,Physics - Chemical Physics ,Physics::Atomic and Molecular Clusters ,FOS: Physical sciences ,Physics::Chemical Physics - Abstract
Ab initio computed interaction forces are employed in order to describe the microsolvation of the A$_2^+(^2\Sigma)$ (A=Li,Na,K) molecular ion in $^4$He clusters of small variable size. The minimum energy structures are obtained by performing energy minimization based on a genetic algorithm approach. The symmetry features of the collocation of solvent adatoms around the dimeric cation are analyzed in detail, showing that the selective growth of small clusters around the two sides of the ion during the solvation process is a feature common to all three dopants.
- Published
- 2007
28. Impact of molecular flexibility on the site energy shift of chlorophylls in Photosystem II
- Author
-
Marco Manzoli, Leonardo Guidoni, Daniele Narzi, Emanuele Coccia, Narzi, Daniele, Coccia, Emanuele, Manzoli, Marco, and Guidoni, Leonardo
- Subjects
Chlorophyll ,DYNAMICS ,0301 basic medicine ,Photosynthetic reaction centre ,Photosystem II ,Lipid Bilayers ,Biophysics ,Thermal fluctuations ,Molecular Dynamics Simulation ,Oxygen-evolving complex ,Cyanobacteria ,010402 general chemistry ,Photosynthesis ,Photochemistry ,01 natural sciences ,Biochemistry ,03 medical and health sciences ,Molecular dynamics ,CRYSTAL-STRUCTURE ,REACTION CENTERS ,Databases, Protein ,OXYGEN-EVOLVING COMPLEX ,WATER OXIDATION ,O-2-EVOLVING COMPLEX ,PROTON RELEASE ,MN-CLUSTER ,S-2 STATE ,RESOLUTION ,Physics::Biological Physics ,030102 biochemistry & molecular biology ,Chemistry ,Organic Chemistry ,Photosystem II Protein Complex ,P680 ,Chromophore ,Protein Structure, Tertiary ,0104 chemical sciences ,Energy Transfer ,Chemical physics ,Thermodynamics - Abstract
Light harvesting from the Sun by antenna complexes surrounding the reaction center of Photosystem II represents the first step of the natural oxygenic photosynthesis performed by plants, algae and cyanobacteria. The excitation energy derived from the sunlight is absorbed by the chlorophylls of the antenna and subsequently conveyed to the reaction center of Photosystem II through resonant energy transfer mechanisms. In the special pair of chlorophylls of the reaction center the charge separation occurs, eventually leading to the oxidation of water molecules into protons, electrons and molecular oxygen. The adsorption properties of the antenna chlorophylls are ad hoc modulated by the protein environment to guarantee fast energy transfer and minimize side and back reactions. At the same time these properties are influenced by the molecular fluctuations occurring at physiological temperature. In the present work, combining classical molecular dynamics simulations with the Charge Density Coupling method, we estimated the impact of the thermal fluctuations on the site energy shift of the chlorophylls embedded in the Photosystem II complex. Our results show how the effect of the molecular fluctuations is not homogeneous throughout the complex, although the symmetry of the homodimer is maintained. Many peripheral chromophores undergo fluctuations larger then 10 kJ/mol around the average values. Possible physiological roles of such fluctuations are discussed.
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