Search results for "Configuration"
showing 10 items of 601 documents
On the dissociation energy of Cu2 and CuH using a differential correlation approach
1990
The energy contributions involved in the “dissociation-consistent configuration interaction” (DCCI) scheme proposed by Goddard and co-workers plus the dispersion effects associated with the valence MOs adjacent to the bond (DISP) are evaluated for the Cu2 and CuH systems, following the “configuration interaction by perturbation with multiconfigurational zeroth-order wavefunction selected by iterative process” (CIPSI) algorithm. Using a relativistic pseudopotential to represent the neon core of copper, and a flexible basis set for the valence shell, the results obtained with the CIPSI/DCCI (+ DISP) approach shows a good agreement with previous theoretical results employing basis sets of simi…
A theoretical study of the electronic spectrum of thiophene
1993
Abstract The electronic spectrum of thiophene has been studied using multiconfiguration second-order perturbation theory and extended ANO basis sets. The calculations comprise four singlet valence excited states and the 3s3p3rd Rydberg series. The lowest triplet states were included and some n-π* and n-σ* states. The results have been used to assign the experimental spectrum below 8.0 eV, with a maximum deviation of about 0.1 eV for vertical transition energies. The calculations place the 2 1A1 valence state at 5.33 eV, below the 1 1B2 valence state at 5.72 eV, and the most intense valence transitions at 6.69 eV (3 1A1) and 7.32 eV (4 1B2) with oscillator strengths 0.19 and 0.39, respective…
Rydberg, valence and mixed states in the vertical spectrum of HF
2009
Abstract Size-consistent self-consistent multireference singles and doubles configuration interaction (SC)2–MR–SDCI, and linear response coupled cluster of singles and doubles including triples LR–CCSDR(3) methods, with a basis set of ANO’s augmented with a single series of molecular Rydberg functions, have been applied to the calculation of vertical excitation energies of HF in the 10–16 eV region. Special care has been put in the description of the valence, Rydberg and mixed states. Some advantage has been taken from the different physical contents of the methods to discuss some assignments. The (4,5) f Rydberg states of HF are predicted at 15.2 and 15.5 eV.
The ACM property for unions of lines in P1×P2
2021
This paper examines the Arithmetically Cohen-Macaulay (ACM) property for certain codimension 2 varieties in P1×P2 called sets of lines in P1×P2 (not necessarily reduced). We discuss some obstacles to finding a general characterization. We then consider certain classes of such curves, and we address two questions. First, when are they themselves ACM? Second, in a non-ACM reduced configuration, is it possible to replace one component of a primary (prime) decomposition by a suitable power (i.e. to “fatten” one line) to make the resulting scheme ACM? Finally, for our classes of such curves, we characterize the locally Cohen-Macaulay property in combinatorial terms by introducing the definition …
Run-Time Reconfiguration for Emulating Transient Faults in VLSI Systems
2006
Advances in circuitry integration increase the probability of occurrence of transient faults in VLSI systems. A confident use of these systems requires the study of their behaviour in the presence of such faults. This study can be conducted using model-based fault injection techniques. In that context, field-programmable gate arrays (FPGAs) offer a great promise by enabling those techniques to execute models faster. This paper focuses on how run-time reconfiguration techniques can be used for emulating the occurrence of transient faults in VLSI models. Although the use of FPGAs for that purpose has been restricted so far to the well-known bit-flip fault model, recent studies in fault repres…
Analytical chemistry on many-center chiral compounds based on vibrational circular dichroism: Absolute configuration assignments and determination of…
2019
The absolute configuration of a chiral molecule is key to its biological activity. Being able to find out what this configuration is, is thus crucial for a wide range of applications. The difficulties associated with such a determination steeply rise as the number of chiral centers in a given compound becomes larger. Concurrently, it becomes increasingly more challenging to determine the levels and identity of potential stereochemical contaminants in a given sample with one and the same technique, leading in practice to extensive and laborious efforts employing multiple analytical techniques. Here, experimental and theoretical studies based on Vibrational Circular Dichroism (VCD) are presen…
Palermo: Virtual urban reconfiguration of some ancient squares and quarters
2013
The representation area is nowaday called upon to face new challenges for new computer technologies that have developed over the last few years. Visual communication and multimedia language experienced a radical change: representation and visualization, thought and image are based on the branch of communication and therefore on the trasmission of knowledge that cannot be separated from the interdisciplinarity. Digital imagery challenges more and more analog imagery, creating a scene that is independent from the constructed reality and sometimes reaching to overlap and merge with it: therefore the representation is no longer just a repetition of the real, but becomes itself an autonomous rea…
Experiments on the Virtual City: Three-Dimensional Reconfigurations of Missing, Never Realized or Destroyed Urban Areas
2011
We present two works on the "Virtual City" held at Palermo. They are about the three-dimensional reconfiguration of urban places that show evidence of "invisible" architecture, this is because in one case there were ancient monuments now destroyed, or in another case projects designed for the urban void and never made. The aim is to involve new forms of communication for the development of cultural tourism.
Panel Summary: Plasticity and Reconfigurability in Sensory Systems
1997
Natural neural network are highly plastic in structure and function and may adapt to long lasting environmental changes. Plasticity and adaptation are not confined to lower level of processing, or to lower vertebrates, but also at the higher levels of visual processing in higher vertebrates are highly dynamic and perform considerable spatial integration. There are numerous influences that play a role in the functional architecture of the retina and the, cortex, the dynamics of the outside environment, the context within which a feature is presented, the history of previous visual stimulation and attention or expectation. The brief report on the visual system is integrated by the report of G…
What Are the Latest Fake News in Romanian Politics? An Automated Analysis Based on BERT Language Models
2021
Social media and news outlets facilitate information sharing, while the Web is flooded by information posted online on a daily basis. However, content may be differently transmitted from case to case, based on the authors’ intentions and vocabulary, to the extent that it generates completely opposite points of view. As such, fake news have become a global phenomenon, and recent events highlight a high impact of distorted or fake information, especially on the political side, when candidates’ discourses include tendentious statements that require careful validation before completely trusting the source. This paper proposes an automated analysis of political statements in Romanian by applying…