1,721,185 research outputs found
Testing van der Waals interactions with quantum dynamics: Repulsive anisotropy and well depth in the LiH plus He system
No full textRecent calculations on the rigid rotor surface for the LiH-He interaction [B. K. Taylor and R. J. Hinde, J. Chem. Phys. 111, 973 (1999)] surmised that the well depth and anisotropy of the new surface differ substantially from the latest valence bond calculations for the same system [F. A. Gianturco, S. Kumar, S. K. Pathak, M. Raimondi, M. Sironi, J. Gerratt, and D. L. Cooper, Chem. Phys. 215, 227 (1997)]. We examine in detail the performance of both these potential energy surfaces once employed to generate quantum observables which can be compared with experiments. Our computations clearly show that the two surfaces exhibit small differences in their short-range repulsive anisotropy and larger differences in well depths. The latter however cannot be assessed as yet from existing experiments. The different behavior of their wells in supporting van der Waals bound states is also examined and spectroscopic experiments are suggested for detecting possible transitions between such states. (C) 2000 American Institute of Physics. [S0021- 9606(00)00341-X]
The Patron Game with Heterogeneous Endowments : A Case Against Inequality Aversion
Full text linkIn this paper we provide a direct test of the inequality aversion hypothesis based on aggregate outcomes using the Patron Game, a version of a Public Good Game that mandates that only one member of a group contributes to the public good. We find evidence that inequality aversion does not play any role, as the average contribution does not increase when the distribution of endowments is manipulated to generate a situation of favorable inequality for the patron, compared to the case in which there is no inequality ex ante
Capitale sociale, istituzioni intermedie e cooperazione tra imprese
No full textAll’origine delle decisioni di cooperazione tra imprese vi sono motivazioni di diversa natura. Nonostante la varietà delle ipotesi interpretative, nella maggioranza dei contributi si assume che le decisioni di azione collettiva siano fondate essenzialmente sulla valutazione dei benefici di cooperazione generati direttamente dalla partecipazione al progetto comune. Più raramente si tiene presente che sia i payoffs da cooperazione che quelli da defezione possano essere modificati da fattori esogeni come la legislazione societaria, le politiche antitrust, la dotazione di capitale sociale, la presenza di incentivi istituzionali, le tradizioni di associazionismo economico.Nel presente lavoro si tenta di verificare la capacità interpretativa di modelli che spiegano la cooperazione tra imprese facendo ricorso non solo a fattori tecnologici, organizzativi e di rivalità tra imprese, ma anche a variabili proxies del capitale sociale, di accumulazione di esperienze di azione collettiva e della capacità di iniziativa delle istituzioni. L’oggetto specifico dello studio è l’interpretazione dei differenziali esistenti nella propensione alla cooperazione tra imprese nei diversi sistemi produttivi locali in Itali
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Application of valence-bond techniques to the study of weakly bound complexes. The potential energy surface of the Ne-CH4 system
No full textWe present a comprehensive survey of the Molecular Orbital-Valence Bond ( MO-VB) method, a theoretical scheme developed within the framework of the Valence Bond theory to deal with weakly bound intermolecular complexes. According to the MO-VB, the wavefunction of the system is expressed as a truncated non-orthogonal Configuration Interaction expansion, which is size extensive and a priori free of basis set superposition error. We report on the recent developments of the method, which extend the range of application of the MO-VB to intermolecular complexes with a quite large number of correlated electrons, showing that VB-based methods are nowadays a valid alternative to Molecular Orbital approaches also in this field. The MO-VB has been applied to study extensively the Ne-CH4 complex, and compared with the more standard MP4 and CCSD( T) results. We determined two analytical Potential Energy Surfaces ( PES) for this system, computed at MO-VB and MP4 level, which represent the first ones coming entirely from ab initio computations. The features of our potentials are discussed, and compared to the single analytical potential which includes the anisotropy available in the literature, determined about twenty years ago by Udo Buck and co-workers using a semiempirical approach [ U. Buck, A. Kolhase, D. Secrest, T. Phillips, G. Scoles and F. Grein, Mol. Phys., 1985, 55, 1233]. The differences among the three PES are quite relevant, and are due to play a relevant role in the theoretical simulations of the dynamical properties of the Ne-CH
Weathering features and morphology on Mt. Mottarone (Northern Italy). An example of a granite weathering landscape
No full textBSSE free MCSCF method for strong hydrogen bonds: investigation of H2O-HCl and NH3-HCl complexes
No full textA Multi-Configuration extension of the Self Consistent Field for Molecular Interaction
method – MCSCF-MI – is presented. Applications to the study of hydrogen bonded
systems are reported. Potential energy, optimal geometry and the characteristic H-Cl
stretching in the H2O-HCl and NH3-HCl complexes were examined. BSSE, which
represents a major problem in the study of the interaction potentials of loosely bonded
fragments, is avoided by the a priori SCF-MI technique. Equilibrium geometries, binding
energies, and vibrational constants computed by both SCF-MI and MCSCF-MI methods
turned out more stable than the corresponding standard SCF calculations upon variation of
the quality of the basis set employed. In particular, the proton transfer process was
examined. All the calculations predicted that the minimum corresponds to hydrogen
bonded structures. In the case of NH3-HCl good agreement with recent extensive MO-CI
and DFT studies was establis
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