Academic literature on the topic 'Electron Localization Function'

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Journal articles on the topic "Electron Localization Function"

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Savin, Andreas, Reinhard Nesper, Steffen Wengert, and Thomas F. Fässler. "ELF: The Electron Localization Function." Angewandte Chemie International Edition in English 36, no. 17 (September 17, 1997): 1808–32. http://dx.doi.org/10.1002/anie.199718081.

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Nalewajski, Roman F., Andreas M. Köster, and Sigfrido Escalante. "Electron Localization Function as Information Measure." Journal of Physical Chemistry A 109, no. 44 (November 2005): 10038–43. http://dx.doi.org/10.1021/jp053184i.

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Pilmé, Julien. "Electron localization function from density components." Journal of Computational Chemistry 38, no. 4 (November 17, 2016): 204–10. http://dx.doi.org/10.1002/jcc.24672.

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Tsirelson, Vladimir, and Adam Stash. "Determination of the electron localization function from electron density." Chemical Physics Letters 351, no. 1-2 (January 2002): 142–48. http://dx.doi.org/10.1016/s0009-2614(01)01361-6.

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Matito, Eduard, Bernard Silvi, Miquel Duran, and Miquel Solà. "Electron localization function at the correlated level." Journal of Chemical Physics 125, no. 2 (July 14, 2006): 024301. http://dx.doi.org/10.1063/1.2210473.

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Krokidis, Xénophon, Nigel W. Moriarty, William A. Lester, Jr, and Michael Frenklach. "Propargyl radical: an electron localization function study." Chemical Physics Letters 314, no. 5-6 (December 1999): 534–42. http://dx.doi.org/10.1016/s0009-2614(99)00880-5.

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Kohout, Miroslav, Frank Richard Wagner, and Yuri Grin. "Electron localization function for transition-metal compounds." Theoretical Chemistry Accounts: Theory, Computation, and Modeling (Theoretica Chimica Acta) 108, no. 3 (October 1, 2002): 150–56. http://dx.doi.org/10.1007/s00214-002-0370-x.

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SAVIN, A., R. NESPER, S. WENGERT, and T. F. FAESSLER. "ChemInform Abstract: ELF: The Electron Localization Function." ChemInform 28, no. 48 (August 2, 2010): no. http://dx.doi.org/10.1002/chin.199748342.

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Shukla, Padma Kant, and Bengt Eliasson. "Localization of intense electromagnetic waves in plasmas." Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 366, no. 1871 (January 24, 2008): 1757–69. http://dx.doi.org/10.1098/rsta.2007.2184.

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We present theoretical and numerical studies of the interaction between relativistically intense laser light and a two-temperature plasma consisting of one relativistically hot and one cold component of electrons. Such plasmas are frequently encountered in intense laser–plasma experiments where collisionless heating via Raman instabilities leads to a high-energetic tail in the electron distribution function. The electromagnetic waves (EMWs) are governed by the Maxwell equations, and the plasma is governed by the relativistic Vlasov and hydrodynamic equations. Owing to the interaction between the laser light and the plasma, we can have trapping of electrons in the intense wakefield of the laser pulse and the formation of relativistic electron holes (REHs) in which laser light is trapped. Such electron holes are characterized by a non-Maxwellian distribution of electrons where we have trapped and free electron populations. We present a model for the interaction between laser light and REHs, and computer simulations that show the stability and dynamics of the coupled electron hole and EMW envelopes.
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Maurya, V., and K. B. Joshi. "Electron Localization Function and Compton Profiles of Cu2O." Journal of Physical Chemistry A 123, no. 10 (March 4, 2019): 1999–2007. http://dx.doi.org/10.1021/acs.jpca.8b12102.

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Dissertations / Theses on the topic "Electron Localization Function"

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Burnus, Tobias. "Time-dependent electron localization function." Berlin : T. Burnus, 2004. http://deposit.d-nb.de/cgi-bin/dokserv?idn=98587676X.

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De, Santis Lorenzo. "Theory of electron Localization Function and its Applications: Surfaces, Impurities and Enzymatic Catalysis." Doctoral thesis, SISSA, 1999. http://hdl.handle.net/20.500.11767/4428.

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Mbouombouo, Ndassa Ibrahim. "Compréhension de mécanisme réactionnel à l'aide de la méthode ELF (Electron Localization Function)." Paris 6, 2010. http://www.theses.fr/2010PA066213.

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Burt, Jason Bryan. "A study of the crystal chemistry, electron density distributions, and hydrogen incorporation in the Al₂SiO₅ polymorphs." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/27756.

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The Al₂SiO₅ polymorphs have been examined to provide new insights into their chemical bonding, their crystal chemistry, their equations of state, and the incorporation of water in the form of hydroxyl in their structures. The Al₂SiO₅ polymorphs provide a unique structural assemblage for a crystal chemical examination due to the variation in Al coordination in the structures where Al is in 4-fold, 5-fold, and 6-fold in sillimanite, andalusite, and kyanite, respectively. Consequently, the Al₂SiO₅ polymorphs have been examined with a combination of experimental (high pressure X-ray diffraction and Polarized FTIR spectroscopy) and theoretical (VASP and Crystal 98) methods. An experimental high pressure X-ray diffraction study on andalusite and sillimanite has constrained their equation of state and the pressure derivatives of their bulk modulus with pressure. Additionally, the effect of pressure on the crystal structures has been examined, where the main structural response is compression of the AlO₆ octahedra. Comparatively, compression of the AlO₆ octahedra in andalusite is more anisotropic, while the major direction of axial compressibility in both structures is dependent on the orientation of the AlO6 octahedra. In order to better understand the crystal chemistry of the Al-O and Si-O bonds in the polymorphs, ELF isosurfaces were examined. ELF isosurfaces represent a graphical representation of the localized electron probability density. Six distinct types of ELF isosurfaces were observed in the Al₂SiO₅ polymorphs resulting from differences in the geometry, coordination, and coordinated cation atomic number surrounding the oxygens within the crystal structures. The ELF was also shown to be isostructurally related to electron density difference maps. In a combined experimental and theoretical investigation of the Al₂SiO₅ polymorphs, potential protonation sites within the crystal structures were determined at an atomic level with polarized FTIR spectroscopy and analysis of (3,-3) critical points of the negative Laplacian. The polarized FTIR spectra indicate the orientation of the OH dipole in the three polymorphs and the (3,-3) critical points indicate regions of locally concentrated electron density. Potential protonation sites were determined based on the value of the negative Laplacian, the underbonded nature of the oxygens, and the number of surrounding cations.
Ph. D.
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El, Khatib Muammar. "Characterization of metallic and insulating properties of low-dimensional systems." Thesis, Toulouse 3, 2015. http://www.theses.fr/2015TOU30198/document.

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Dans cette thèse nous avons étudié des indicateurs visant à caractériser les propriétés métalliques ou isolantes de systèmes de basse dimensionnalité à partir de calculs théoriques basés sur la fonction d'onde. Ces systèmes sont intéressants car ils permettent une compréhension en profondeur des phénomènes physiques qui peuvent ensuite être extrapolés à des systèmes plus étendus. Afin de réaliser cette étude nous avons utilisé un nouvel outil basé sur la théorie de la conductivité de Kohn : le tenseur de délocalisation total ou total position spread-tensor (TPS). Ce tenseur est défini comme le second cumulant de l'opérateur position : ? = - 2. Divisé par le numéro des électrons, il diverge quand la fonction d'onde est fortement délocalisée (forte fluctuation de la position des électrons) et converge vers une valeur finie dans le cas contraire. Ainsi, la conductivité est relié à la délocalisation de la fonction d'onde. Dans ce travail, deux définitions du TPS ont été abordées : une quantité sommée sur le spin (spin-summed TPS, SS-TPS) d'une part, et une décomposition selon le spin (spin-partitioned TPS, SSP-TSP) d'autre part. Cette dernière s'est avérée être un outil très efficace pour l'étude de systèmes fortement corrélés. Au cours de la thèse, nous avons commencé par étudier plusieurs systèmes diatomiques présentant des liaisons de natures différentes à l'aide de calculs d'interaction de configurations totale (FCI). Le TPS présente alors un maximum dans une zone précédant la rupture de liaison avant de converger asymptotiquement vers les valeurs atomiques, comme la consistance de taille du tenseur le laissait présager. Dans le cas de systèmes pour lesquels l'état électronique présente un croisement évité, le TPS diverge, mettant ainsi en évidence la forte délocalisation de la fonction d'onde. Le SS-TPS est donc un indicateur de choix pour suivre la nature de la liaison chimique. Nous avons ensuite considéré des systèmes à valence mixte de type II pour lesquels l'état fondamental présente un double-puits de potentiel avec un croisement évité avec le premier état excité. Il est donc nécessaire ici d'utiliser un traitement multi-configurationnel. Deux systèmes modèles ont ainsi été étudiés : i) deux di- mères H2 en interaction faible au niveau FCI et ii) un composé du type spiro au niveau CAS-SCF (à l'aide d'un code que nous avons implémenté dans Molpro). Dans les deux cas, le TPS présentait un maximum très marqué dans la région du croisement évité, signature d'une forte mobilité électronique. Nous nous sommes également intéressés à trois types de chaines d'atomes d'hydrogène : i atomes équidistants ii) chaines dimérisées à longueur de liaison H2 fixée et iii) chaines dimérisées. Tant le SS-TPS que le SP-TPS montrent des comportements différents selon le type de chaine considérée. Les premières ont un caractère métallique et une délocalisation de spin prononcée dans le régime fortement corrélé. Les secondes sont de nature isolante avec une délocalisation limitée. Les chaines dimérisées, quant à elle, dissocient très rapidement vers un état isolant mais avec une forte délocalisation de spin. Ces chaines demi-remplies ont aussi été traitées à l'aide d'hamiltonien de Hubbard et de Heisenberg. Nous avons ainsi pu rationaliser le comportement des SS-TPS et SP-TPS en variant le rapport de l'intégrale de saut et de la répulsion électron- électron (-t/U) entre sites adjacents. Le caractère ferromagnétique/anti-ferromagnétique a également pu être suivi en modifiant la valeur de la constante de couplage J dans le cas fortement corrélé. Finalement, ces indicateurs ont été mis en oeuvre pour des polyacenes cycliques. Dans ce cas, le TPS a permis de comprendre la nature des fonctions d'onde de l'état fondamental obtenues au niveau CAS-SCF et NEVPT2
I carried out a theoretical study to characterize metallic and insulating properties of low-dimensional systems using wave function methods. Low-dimensional systems are particularly important because they allow an understanding that can be extrapolated to higher dimensional systems. We have employed a new tool based on the theory of conductivity of Kohn that we have named: total position-spread tensor (TPS). The TPS is defined as the second moment cumulant of the total position operator: ? = - 2 . The tensor divided by the number of electrons diverges when the wave function is delocalized (high fluctuation of electrons' positions), and it takes finite values for localized ones. In this way, the electrical conductivity is related to the proper delocalization of the wave function. In addition, the tensor can be divided in spin-summed (SS-TPS) and spin-partitioned tensors (SP-TPS). The latter one becomes a powerful tool to the study of strongly correlated systems. In this dissertation, we started to investigate at full configuration interaction (FCI) level diatomic molecules showing different types of bond. The TPS presented a marked maximum before the bond was broken and in the asymptotic limit one recovers the TPS values of isolated atoms (size consistency). For the case of diatomic systems showing avoided-crossing electronic states, the TPS diverges evidencing the high delocalization of the wave function. Therefore, the SS-TPS is capable of monitoring and characterizing molecular wave functions. We considered mixed-valence systems that are often distinguished by a double-well potential energy surface presenting an avoided-crossing. Thus, such a configuration possesses a strongly multireference nature involving at least two states of the same symmetry. Two different systems were investigated: i) two weakly interacting hydrogen dimers that were investigated at Full CI level, and ii) a spiro like molecule where the TPS tensor was evaluated in a CAS-SCF state-averaged wave function using our implementation of the SS- TPS formalism in MOLPRO. We found that the tensor's component in the direction of the electron transfer (ET) shows a marked maximum in the avoided-crossing region, evidencing the presence of a high electron mobility. The formalisms of the SS- and SP-TPS was applied to one dimensional systems composed by three types of half-filled hydrogen chains: i) equally-spaced chains, ii) fixed-bond dimerized chains, and iii) homothetic dimerized chains. Both the SS- and SP-TPS showed different signatures associated to the three types of systems. Equally-spaced chains have metallic wave functions and a high spin delocalization in the strongly correlated regime. In contrast, fixed-bond dimerized chains have an insulating character and a restricted spin delocalization. Finally, homothetic dimerized chains dissociate very quickly which renders them in the insulating state but with a high spin delocalization. We also studied half-filled chains by using the Hubbard and the Heisenberg Hamiltonians. On the one hand, we were able to depict the response of the SS- and SP-TPS by varying the ratio between the hopping and electron-electron repulsion (-t/U parameter) of topological connected sites. On the other hand, the ferromagnetic and anti-ferromagnetic character of the wave functions were evaluated by varying the coupling constant (J) in the strongly correlated systems. A theoretical study of closed polyacenes (PAH) structures was performed at CAS-SCF and NEVPT2 level. Our methodology for choosing the active space using the Hückel Hamiltonian was able to characterize the ground state of the systems that indeed fulfilled the Ovchinnikov rule. Finally, we applied the SS-TPS to understand the nature of the wave functions of these PAHs
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Thébaud, Simon. "Electron and phonon transport in disordered thermoelectric materials : dimensional confinement, resonant scattering and localization." Thesis, Lyon, 2019. http://www.theses.fr/2019LYSE1168/document.

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Ces dernières décennies, l'urgence croissante de la crise énergétique et la prise de conscience qu'une grande partie de l'énergie utilisée dans le monde est dissipée sous forme de chaleur ont provoqué un engouement pour le développement de modules thermoélectriques performants. Ces dispositifs pourraient récupérer la chaleur provenant de procédés industriels ou d'autres sources, transformant un gradient de température en voltage grâce à l'effet Seebeck. Les matériaux thermoélectriques performants doivent posséder une faible conductivité thermique, une haute conductivité électrique et un grand coefficient Seebeck. L'optimisation simultanée de ces paramètres est un défi majeur pour la physique de la matière condensée et la science des matériaux. Dans l'optique d'améliorer les propriétés thermoélectriques de plusieurs matériaux prometteurs, nous explorons plusieurs stratégies dans lesquelles les défauts (substitutions atomiques, lacunes…), le désordre et le confinement dimensionnel jouent un rôle central. Nous réalisons des calculs en théorie de la fonctionnelle densité et des projections sur des orbitales de Wannier afin de construire des Hamiltoniens et des matrices dynamiques réalistes décrivant leur structure électronique et vibrationnelle dans l'espace réel. Ces paramètres sont ensuite utilisés pour calculer les propriétés de transport thermoélectrique en utilisant le formalisme de Kubo, l'équation de Boltzmann, le formalisme de Landauer et la méthode Chebyshev polynomial Green's function, qui permet un traitement exact du désordre. Nous étudions les propriétés de transport électronique et les performances thermoélectriques de deux matériaux prometteurs pour la production d'énergie à hautes températures, le titanate de strontium et l'oxyde de titane rutile. Nous obtenons un très bon accord entre nos prédictions et un grand nombre de données expérimentales. Nous montrons que l'augmentation du coefficient Seebeck observée dans les superlayers de titanate de strontium, jusque-là attribuée à des effets de confinement quantique, est en réalité très bien expliquée par l'hypothèse d'électrons délocalisés. Nous explorons les effets généraux des états résonant sur le transport électronique dans le cadre d'une étude modèle, et nous trouvons une augmentation d'un facteur six des performances thermoélectriques. Nous examinons ensuite le cas particulier du titanate de strontium, et nous montrons que les performances sont détruites par des effets de localisation si des atomes de Vanadium sont introduits comme impuretés résonantes. Nous étudions l'influence des défauts dans les matériaux bidimensionnels. Contrairement aux adatomes, nous montrons que les substitutions dans les dichalcogénures de métaux de transition ont pour effet de localiser les porteurs de charge. Nous étudions l'effet des lacunes sur le transport de phonons dans le graphène, et nous déterminons les taux de diffusion phonon-lacune. Nous obtenons un très bon accord entre notre théorie et des mesures de conductivité thermique dans des échantillons de graphène irradiés et de tailles finies
Over the past decades, the increasingly pressing need for clean energy sources and the realization that a huge proportion of the world energy consumption is wasted in heat have prompted great interest in developing efficient thermoelectric generation modules. These devices could harvest waste heat from industrial processes or other sources, turning a temperature gradient into a voltage through the Seebeck effect. Efficient thermoelectric materials should exhibit a low thermal conductivity, a high electrical conductivity and a high Seebeck coefficient. Simultaneously optimizing these parameters is a great challenge of condensed matter physics and materials science. With a view to enhance the thermoelectric properties of several promising materials, we explore several strategies in which defects (atomic substitutions, vacancies…), disorder and dimensional confinement play a crucial role. We perform density functional theory calculations and projections on Wannier orbitals to construct realistic Hamiltonians and dynamical matrices describing their electronic and vibrational structure in real space. These parameters are then used to compute the thermoelectric transport properties using the Kubo formalism, the Boltzmann transport equation, the Landauer formalism, and the Chebyshev polynomial Green's function method that allows for an exact treatment of disorder. We investigate the electronic transport properties and thermoelectric performances of two promising materials for high-temperature power generation, strontium titanate and rutile titanium dioxide. Comparison of our predictions with a wealth of experimental data yields a very good agreement. We show that the increase of the Seebeck coefficient observed in strontium titanate superlayers, until now attributed to quantum confinement effects, is in fact well explained assuming delocalized electrons. The general effects of resonant states on electronic transport are explored in a model study, showing a sixfold increase of the thermoelectric performances. The particular case of strontium titanate is then examined, and localization effects are shown to destroy the performances if Vanadium atoms are introduced as resonant impurities. The influence of defects in two-dimensional materials is investigated. Contrary to adatoms, substitutions in transition metal dichalcogenides are shown to localize the charge carriers. We study the effect of vacancies on phonon transport in graphene, and determine the phonon-vacancy scattering rate. Comparison with thermal conductivity data for irradiated and finite-size graphene samples yields a very good agreement between theory and experiments
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Santana-Bonilla, Alejandro. "Density functional theory and model-based studies of charge transfer and molecular self-organization on surfaces:." Doctoral thesis, Saechsische Landesbibliothek- Staats- und Universitaetsbibliothek Dresden, 2017. http://nbn-resolving.de/urn:nbn:de:bsz:14-qucosa-222478.

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Molecular-based quantum cellular automata (m-QCA), as an extension of quantum-dot QCAs, offer a novel alternative in which binary information can be encoded in the molecular charge configuration of a cell and propagated via nearest-neighbor Coulombic cell-cell interactions. Appropriate functionality of m-QCAs involves a complex relationship between quantum mechanical effects, such as electron transfer processes within the molecular building blocks, and electrostatic interactions between cells. In the first part of this document, the influence of structural distortions in single m-QCA is addressed within a minimal model using an diabatic-to-adiabatic transformation. Thus, it is shown that even small changes of the classical square geometry between driver and target cells, such as those induced by distance variations or shape distortions, can make cells respond to interactions in a far less symmetric fashion, modifying and potentially impairing the expected computational behavior of the m-QCA. The model has been further extended to consider time-dependent external electric fields in which a special emphasis is given to the profiles in which this external parameter can interact with the associated molecular complex. The results of the model have been validated by a direct comparison with first-principle calculations allowing to conclude the plausibility to induce the intra-molecular charge transfer process in a controllable manner via the interaction with the external electric field. The influence played by the electric field profile in the response of the molecular complex is also investigated. The results suggests a major role played by this variable in terms of the time length in which the intra-molecular charge transfer can be observed. In the second part, first-principle theoretical calculations of the self-assembly properties and electronic structure of Ferrocene-functionalized complexes have been carried out. Hence, five different molecular complexes which offer a potential playground to realistic implement the m-QCA paradigm have been investigated. The main emphasis is given to study the interaction between localized charge-carrier molecular states and the delocalized surface states. The results of these calculations demonstrate the possibility to obtain real systems in which intra-molecular charge localization can be combined with self-assembly scaffolding and absorbed on either Highly oriented pyrolytic graphite (HOPG) or metallic-surfaces. Finally, the validation of these findings is carried out via comparison with accesible experimental results and opening the gate to plausible strategies where the paradigm can be implemented.
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Teichert, Fabian, Andreas Zienert, Jörg Schuster, and Michael Schreiber. "Electronic transport through defective semiconducting carbon nanotubes." IOP Publishing Ltd, 2018. https://monarch.qucosa.de/id/qucosa%3A32462.

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We investigate the electronic transport properties of semiconducting (m, n) carbon nanotubes (CNTs) on the mesoscopic length scale with arbitrarily distributed realistic defects. The study is done by performing quantum transport calculations based on recursive Green's function techniques and an underlying density-functional-based tight-binding model for the description of the electronic structure. Zigzag CNTs as well as chiral CNTs of different diameter are considered. Different defects are exemplarily represented by monovacancies and divacancies. We show the energy-dependent transmission and the temperature-dependent conductance as a function of the number of defects. In the limit of many defetcs, the transport is described by strong localization. Corresponding localization lengths are calculated (energy dependent and temperature dependent) and systematically compared for a large number of CNTs. It is shown, that a distinction by (m − n)mod 3 has to be drawn in order to classify CNTs with different bandgaps. Besides this, the localization length for a given defect probability per unit cell depends linearly on the CNT diameter, but not on the CNT chirality. Finally, elastic mean free paths in the diffusive regime are computed for the limit of few defects, yielding qualitatively same statements.
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Teichert, Fabian. "Elektronischer Transport in defektbehafteten quasi-eindimensionalen Systemen am Beispiel von Kohlenstoffnanoröhrchen." Master's thesis, Universitätsbibliothek Chemnitz, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-qucosa-139650.

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Die vorliegende Arbeit beschäftigt sich mit den Transporteigenschaften defektbehafteter Kohlenstoffnanoröhrchen (CNTs). Als Beispiel werden dabei einfache und doppelte Fehlstellen betrachtet. Der Fokus liegt auf der Berechnung des Transmissionsspektrums und der Leitfähigkeit mit einem schnellen, linear skalierenden rekursiven Greenfunktions-Formalismus, mit dem große Systeme quantenmechanisch behandelt werden können. Als Grundlage wird ein dichtefunktionalbasiertes Tight-Binding-Modell verwendet. Der Einfluss der Defektdichte und des CNT-Durchmessers wird im Rahmen einer statistischen Analyse untersucht. Es wird gezeigt, dass im Grenzfall kleiner Transmission die Leitfähigkeit exponentiell mit der Defektanzahl skaliert. Das System befindet sich im Regime starker Lokalisierung, wobei die Lokalisierungslänge von der Defektdichte und dem CNT-Durchmesser abhängt.
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Pramanik, Saurav. "Complex Network-Function-Loci For Localization Of Discrete Change In Transformer Windings." Thesis, 2010. http://etd.iisc.ernet.in/handle/2005/1327.

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Large capacity high voltage power transformers are one of the most expensive items of equipment in an electrical power network. Power utilities can ill-afford breakdown of transformers, especially, in a deregulated scenario. The consequences of such a failure are well known. Under these circumstances, utilities have figured-out that condition-based monitoring and diagnosis is worth pursuing, in spite of increased expenditure. Thus, monitoring and diagnosis is an integral part of operation and maintenance. Mechanical forces generated during short-circuits is the main cause leading to displacement/deformation of windings. Frequency response measurements have attained worldwide acceptance as a highly sensitive monitoring tool for detecting occurrence of such events. This is evident from the fact that customized commercial equipment are available (popularly called FRA or SFRA instruments), and with recent introduction of an IEEE draft trial-use guide for application and interpretation of frequency response analysis. Once a damage is detected, the next task is to identify its location along the winding and, if possible, determine its extent of severity. Understandably, these two tasks are best achieved, without disassembling the transformer and should ideally be based on off-line and on-site terminal measurements. In this regard, literature analysis reveals that recent research efforts have successfully demonstrated possibilities of using frequency response data for localization of discrete change in windings. This is indeed noteworthy, in spite of one major drawback. This pertains to excessive computing time needed to synthesize large-sized ladder-network, which automatically limits its practical use. Keeping these issues in mind, a research was initiated to find alternatives. The primary objective of this thesis is to examine the use of- • Complexnetwork-function-lociforlocalizationofadiscretechangeinasingle,isolatedtransformerwinding,basedonterminalmeasurements It goes without saying that the proposed method should be non-invasive, simple, time-efficient and overcome drawbacks in the earlier approach. A brief summary of the proposed method follows- This thesis presents a different approach to tackle the problem of localization of winding deformation in a transformer. Within the context of this thesis, winding deformation means, a discrete and specific change imposed at a particular position on the winding. The proposed method is based on the principle of pre-computing and plotting the complex network-function-loci (e.g. driving-point-impedance) at a selected frequency, for a meaningful range of values for each element (increasing and decreasing) of the ladder network. This loci diagram is called the nomogram. After introducing a discrete change (to simulate a deformation), the driving-point-impedance (amplitude and phase) is measured again .By plotting this single measurement on the nomogram, it is straightforward to estimate the location and identify the extent of change. In contrast to the earlier approach (wherein the entire ladder-network had to be synthesized for every new measurement), the proposed method overcomes the drawbacks, is non-iterative and yields reasonably accurate localization. Experimental results on a model coil and two actual transformer windings (continuous-disc and interleaved-disc) were encouraging and demonstrate its potential. Further details are presented in the thesis.
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Books on the topic "Electron Localization Function"

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Helena, Knotkova, Cruciani Ricardo, and Merrick Joav 1950-, eds. Pain: Brain stimulation in the treatment of pain. Hauppauge, N.Y: Nova Science Publishers, 2009.

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Pain: Brain stimulation in the treatment of pain. New York: Nova Science Publishers, 2010.

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Brain stimulation in psychiatry: ECT, DBS, TMS, and other modalities. Cambridge: Cambridge University Press, 2012.

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Shils, Jay L., Sepehr Sani, Ryan Kochanski, Mena Kerolus, and Jeffrey E. Arle. Recording Techniques Related to Deep Brain Stimulation for Movement Disorders and Responsive Stimulation for Epilepsy. Edited by Donald L. Schomer and Fernando H. Lopes da Silva. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190228484.003.0038.

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Neuromodulation therapies are now common treatments for a variety of medically refractory disorders, including movement disorders and epilepsy. While surgical techniques for each disorder vary, electricity is used by both for relieving symptoms. During stereotactic placement of the stimulating electrode, either deep brain stimulation electrodes or cortical strip electrodes, intraoperative neurophysiology is used to localize the target structure. This physiology includes single-unit recordings, neurostimulation evoked response evaluation, and intracranial electroencephalography (EEG) to ensure the electrode leads are in the optimal location. Because the functional target for the responsive neurostimulator is more easily visualized on preoperative magnetic resonance imaging, intraoperative physiology is used more as a confirmatory tool, in contrast to the more functional localization-based use during electrode placement for movement disorders. This chapter discusses surgical placement of the electrodes for each procedure and the physiological guidance methodology used to place the leads in the optimal location.
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Michel, Christoph M., and Bin He. EEG Mapping and Source Imaging. Edited by Donald L. Schomer and Fernando H. Lopes da Silva. Oxford University Press, 2017. http://dx.doi.org/10.1093/med/9780190228484.003.0045.

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This chapter describes methods to analyze the scalp electric field recorded with multichannel electroencephalography (EEG). With advances in high-density EEG, systems now allow fast and easy recording from 64 to 256 channels simultaneously. Pattern-recognition algorithms can characterize the topography of scalp electric fields and detect changes in topography over time and between experimental or clinical conditions. Methods for estimating the sources underlying the recorded scalp potential maps have increased the spatial resolution of EEG. The use of anatomical information in EEG source reconstruction has increased the precision of EEG source localization. Algorithms of functional connectivity applied to the source space allow determination of communication between large-scale brain networks in certain frequencies and identification of the directionality of this information flow and detection of crucial drivers in these networks. These methods have boosted the use of EEG as a functional neuroimaging method in experimental and clinical applications.
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Book chapters on the topic "Electron Localization Function"

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Putz, Mihai V. "Electron Localization Function." In New Frontiers in Nanochemistry, 133–42. Includes bibliographical references and indexes. | Contents: Volume 1. Structural nanochemistry – Volume 2. Topological nanochemistry – Volume 3. Sustainable nanochemistry.: Apple Academic Press, 2020. http://dx.doi.org/10.1201/9780429022937-14.

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Beaudet, A., E. Hamel, K. Leonard, M. Vial, E. Moyse, P. Kitabgi, J. P. Vincent, and W. Rostène. "Autoradiographic Localization of Brain Peptide Receptors at the Electron Microscopic Level." In Neurotransmitters and Cortical Function, 547–63. Boston, MA: Springer US, 1988. http://dx.doi.org/10.1007/978-1-4613-0925-3_35.

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Thiry, Marc, and Lydia Thiry-Blaise. "Electron Microscope Localization of Ribosomal RNA and DNA after in Situ Hybridization." In Nuclear Structure and Function, 173–76. Boston, MA: Springer US, 1990. http://dx.doi.org/10.1007/978-1-4613-0667-2_36.

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Contreras-García, Julia, Miriam Marqués, Bernard Silvi, and José M. Recio. "Bonding Changes Along Solid-Solid Phase Transitions Using the Electron Localization Function Approach." In Modern Charge-Density Analysis, 625–58. Dordrecht: Springer Netherlands, 2011. http://dx.doi.org/10.1007/978-90-481-3836-4_18.

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Marino, Tiziana, Maria C. Michelini, Nino Russo, Emilia Sicilia, and Marirosa Toscano. "The nature of the C–As bonds in arsaalkynes: an atoms in molecules and electron localization function study." In Vincenzo Barone, 53–65. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-34462-6_7.

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"An Introduction to the Electron Localization Function." In Chemical Reactivity Theory, 299–310. CRC Press, 2009. http://dx.doi.org/10.1201/9781420065442-24.

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Fuentealba, P., D. Guerra, and A. Savin. "An Introduction to the Electron Localization Function." In Chemical Reactivity Theory. CRC Press, 2009. http://dx.doi.org/10.1201/9781420065442.ch20.

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"Using the Electron Localization Function to Measure Aromaticity." In Aromaticity and Metal Clusters, 117–24. CRC Press, 2010. http://dx.doi.org/10.1201/ebk1439813348-10.

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Fuentealba, Patricio, E. Chamorro, and Juan C. Santos. "Chapter 5 Understanding and using the electron localization function." In Theoretical and Computational Chemistry, 57–85. Elsevier, 2007. http://dx.doi.org/10.1016/s1380-7323(07)80006-9.

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Meis, Constantin. "Quantized Field of Single Photons." In Single Photon Manipulation. IntechOpen, 2020. http://dx.doi.org/10.5772/intechopen.88378.

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We present theoretical developments expressing the physical characteristics of a single photon in conformity with the experimental evidence. The quantization of the electromagnetic field vector potential amplitude is enhanced to a free of cavity photon state. Coupling the Schrödinger equation with the relativistic massless particle Hamiltonian to a symmetrical vector potential relation, we establish the vector potential - energy equation for the photon expressing the simultaneous wave-particle nature of a single photon, an intrinsic physical property. It is shown that the vector potential can be naturally considered as a real wave function for the photon entailing a coherent localization probability. We deduce directly the electric and magnetic field amplitudes of the cavity-free single photon, which are revealed to be proportional to the square of the angular frequency. The zero-energy electromagnetic field ground state (EFGS), a quantum vacuum real component, issues naturally from Maxwell’s equations and the vector potential quantization procedure. The relation of the quantized amplitude of the photon vector potential to the electron-positron charge results directly showing the physical relationship between photons and electrons-positrons that might be at the origin of their mutual transformations. It becomes obvious that photons, as well as electrons-positrons, are issued from the same quantum vacuum field.
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Conference papers on the topic "Electron Localization Function"

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Noordam, L. D., A. ten Wolde, H. G. Muller, A. Lagendijk, and H. B. van Linden van den Heuvell. "Chirped Atomic Electron Wave Packets." In International Conference on Ultrafast Phenomena. Washington, D.C.: Optica Publishing Group, 1990. http://dx.doi.org/10.1364/up.1990.wc1.

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A coherent superposition of atomic electron eigenstates gives rise to localization of the wave function. Creation and detection of these so-called wave packets is possible by picosecond dye lasers. In this contribution we describe two kinds of wave packets, and one application: radial wave packets (1-3) created by a superposition of n-states; parabolic wave packets (4,5) created by a superposition of k-states; finally we will show that the chirped character of these matter waves can be used to shorten optical pulses (6).
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Chang, Chung-Huan, Pei-Ning Hsu, Yu-Min Chung, Nan-Tzu Lian, Ta-Hone Yang, Kuang-Chao Chen, and Chih-Yuan Lu. "Word Line Defect Localization Methods in 2D NAND Flash." In ISTFA 2020. ASM International, 2020. http://dx.doi.org/10.31399/asm.cp.istfa2020p0042.

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Abstract In this work, two analysis methods for word line (WL) defect localization in NAND flash memory array are presented. One is to use the Emission Microscope (EMMI) and Optical Beam Induced Resistance Change (OBIRCH) to analyze the device through backside, which has no risk of damage during sample preparation. Depending on the I-V characteristics of defects, different analysis tools can be applied. The second method is to analyze a device defect location that is hard to detect through backside analysis. The precise defect site can be localized by Electron Beam Induce Resistance Change (EBIRCH) [1,2], and the defect profile can be observed. The large memory array in NAND flash structure leads to the wide sample movement during EBIRCH analysis. The sub-stage movement function used successfully solves this problem.
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Brand, Sebastian, Michael Kögel, Christian Grosse, Frank Altmann, Brian Lai, Qingqing Wang, James Vickers, David Tien, Bernice Zee, and Qiu Wen. "Advanced 3D Localization in Lock-in Thermography Based on the Analysis of the TRTR (Time-Resolved Thermal Response) Received Upon Arbitrary Waveform Stimulation." In ISTFA 2019. ASM International, 2019. http://dx.doi.org/10.31399/asm.cp.istfa2019p0001.

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Abstract Lock-in thermography (LIT) has been successfully applied in different excitation and analysis modes including classical LIT, analysis of the time-resolved temperature response (TRTR) upon square wave excitation and TRTR analysis in combination with arbitrary waveform stimulation. The results obtained by both classical square wave- and arbitrary waveform stimulation showed excellent agreement. Phase and amplitudes values extracted by classical LIT analysis and by Fourier analysis of the time resolved temperature response also coincided, as expected from the underlying system theory. In addition to a conceptual test vehicle represented by a point-shaped thermal source, two semiconductor packages with actual defects were studied and the obtained results are presented herein. The benefit of multi-parametric imaging for identification of a defect’s lateral position in the presence of multiple hot spots was also demonstrated. For axial localization, the phase shift values have been extracted as a function of frequency [4]. For comparative validation, LIT analyses were conducted in both square wave and arbitrary waveform excitation using custom designed and sample-specific stimulation signals. In both cases result verification was performed employing X-ray, scanning electron microscopy (SEM) and energy dispersive x-ray (EDX) as complementary techniques.
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Srebro, Richard. "Cortical activity localized by the Laplacian of the evoked potential field on the scalp." In Noninvasive Assessment of Visual Function. Washington, D.C.: Optica Publishing Group, 1985. http://dx.doi.org/10.1364/navf.1985.wb1.

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The Laplacian of the potential field on the scalp ∇ 2 V= ∂ 2 V ∂ x 2 + ∂ 2 V ∂ y 2 , where V(x,y,t) is the time-varying potential field in x,y scalp dimensions, can be conveniently estimated using 5 electrodes arranged as a cross to measure the sum of orthogonal second differences (Laplacian derivation). The three concentric sphere model of the human head was used to assess some important properties. The Laplacian derivation may be represented by a spatial filter through which brain activity is "seen". The point spread function has a "Mexican hat" shape, or equivalently, brain activity is seen through a spatial bandpass filter different from that of a conventional, "monopolar", electrode derivation which approximates a lowpass filter. As the distance between the individual electrodes of the Laplacian derivation is made smaller, the peak spatial frequency increases, the bandpass narrows, sidelobes become increasingly prominent, and overall signal-to-noise decreases. At a distance of 2.5 cm between individual electrodes, the ratio of spatial resolution (approximately 2.0 cm, bandpass approximately .3 to 1.6 cycles per cm on the surface of the cortex) to signal-to-noise is nearly optimal. The Laplacian derivation is about ten times more sensitive to radially oriented than to tangentially oriented source-sink configurations. Thus, the Laplacian derivation has several useful attributes for localization studies, i.e. it is reference free, sensitive mostly to activity in the cortical mantle, has a resolution of 2 cm or better, and is insensitive to alpha activity. Because the passive properties of the head are nearly linear, no inversion of scalp potential field to yield a unique configuration of the underlying brain activity is in general possible without initial highly restrictive assumptions. But, the initial assumption required when the Laplacian derivation is used is relaxed to one concerning the dimension of the cortical region activated.
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Niu, Hui. "First-Principle Investigation of Structural, Elastic, Electronic and Thermal Properties of Dysprosium Hafnate Oxides." In ASME 2018 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2018. http://dx.doi.org/10.1115/imece2018-87099.

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Systematic first-principles calculations based on density functional theory were performed on Dy2HfxO3+2x (x = 0, 1, and 2) compositions. A complete set of elastic parameters including elastic constants, Hill’s bulk moduli, Young’s moduli, shear moduli and Poisson’s ratio were calculated. Analyses of densities of states and charge densities and electron localization functions suggest that the oxide bonds are highly ionic with some degree of covalency in the Hf-O bonds. Thermal properties including the mean sound velocity, Debye temperature, and minimum thermal conductivity were obtained from the elastic constants.
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Hao, Ma, Zhou Lin, Hu Hongmei, and Wu Zhenyang. "A Novel Sound Localization Method Based on Head Related Transfer Function." In 2007 8th International Conference on Electronic Measurement and Instruments. IEEE, 2007. http://dx.doi.org/10.1109/icemi.2007.4351175.

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Ouyang, Keqing, Xixiong Wei, Xinyi Lin, Dan Yang, Na Mei, and Tuobei Sun. "Fault Localization of Functional Failure by using Dynamic EMMI Analysis Technique." In 2022 23rd International Conference on Electronic Packaging Technology (ICEPT). IEEE, 2022. http://dx.doi.org/10.1109/icept56209.2022.9873274.

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Wen, Fang. "AP1000 Operation Procedures System and Development." In 18th International Conference on Nuclear Engineering. ASMEDC, 2010. http://dx.doi.org/10.1115/icone18-29316.

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This paper makes a brief introduction on AP1000 operation procedure system, including procedure classification, function and composition. In addition, key points of work flow process and the advantages of AP1000 operation procedures are described, among which the application of CPS (computerized procedure system) on AP1000 operation area and human factor engineering are highlighted. CPS, as an advanced procedure system, which is relatively new to existing nuclear power plants in China, does not only have the function of electronic indication for procedures, but also have the ability to monitor plant data, process the data and then present the status of the procedure steps to the reactor operator. Moreover, based on current situation, this paper offers several suggestions on procedure development for Sanmen AP1000 nuclear power project, i.e. first, we can ensure the quality of operation procedures by preparing a precise writer’s guideline, a friendly-interfaced procedure template, an efficient work configuration and an appropriate schedule; then determine the way how we are going to use operation procedures in English version; finally realize CPS Chinesization and localization gradually by digesting and absorbing API 000 technology from Westinghouse Electric Company. This paper gives an intact and systematic discourse on AP1000 operation procedure system and its characteristics. Besides, the latter part of this paper focuses on development of AP1000 operation procedures for Sanmen nuclear power plant and it would be a worthwhile reference for newly-built AP1000 units in China.
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Breitenstein, O., J. P. Rakotoniaina, F. Altmann, J. Schulz, and G. Linse. "Fault Localization and Functional Testing of ICs by Lock-in Thermography." In ISTFA 2002. ASM International, 2002. http://dx.doi.org/10.31399/asm.cp.istfa2002p0029.

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Abstract In this paper new thermographic techniques with significant improved temperature and/or spatial resolution are presented and compared with existing techniques. In infrared (IR) lock-in thermography heat sources in an electronic device are periodically activated electrically, and the surface is imaged by a free-running IR camera. By computer processing and averaging the images over a certain acquisition time, a surface temperature modulation below 100 µK can be resolved. Moreover, the effective spatial resolution is considerably improved compared to stead-state thermal imaging techniques, since the lateral heat diffusion is suppressed in this a.c. technique. However, a serious limitation is that the spatial resolution is limited to about 5 microns due to the IR wavelength range of 3 -5 µm used by the IR camera. Nevertheless, we demonstrate that lock-in thermography reliably allows the detection of defects in ICs if their power exceeds some 10 µW. The imaging can be performed also through the silicon substrate from the backside of the chip. Also the well-known fluorescent microthermal imaging (FMI) technique can be be used in lock-in mode, leading to a temperature resolution in the mK range, but a spatial resolution below 1 micron.
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Ohnishi, Masato, Yang Meng, Ken Suzuki, and Hideo Miura. "Change in Spatial Distribution of State Densities of Carbon Nanotubes Under Anisotropic Strain Field." In ASME 2014 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2014. http://dx.doi.org/10.1115/imece2014-39470.

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In any electronic devices and sensors, unexpected changes in their function occur due to internal strain caused by contact of different materials which leads to thermal deformation or lattice mismatch. Thus, understanding of the effect of strain on electronic properties of carbon nanotubes (CNTs) is indispensable for assuring the reliability of CNTs-based electronic devices and for developing new electronic devices and sensors. In this study, the change in spatial distribution of state densities of zigzag CNTs under radial strain is analyzed by using first-principles calculation. The analysis shows that when a radial strain is applied to a CNT, its state densities are localized at high curvature regions. Such localization of state densities decrease their energies, and then decrease the band gap. In addition, since the behavior of the state energy under the radial strain is dominated by its spatial distribution, the strain sensitivity of CNTs depends on their chirality. The founding gives a guideline on how to fabricate high-performance novel CNTs devices, sensors, for example, biaxial strain sensor.
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