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Dissertations / Theses on the topic 'Initial density'

Author: Grafiati

Published: 2 June 2025

Last updated: 31 July 2025

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1

Hernandez, Miriam B. "Predicting kindergarten reading outcomes from initial language and literacy skills does dialect density matter? /." Tallahassee, Florida : Florida State University, 2010. http://etd.lib.fsu.edu/theses/available/etd-04122010-234627/.

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Thesis (M.S.)--Florida State University, 2010.<br>Advisor: Stephanie Al Otaiba, Florida State University, College of Education, Dept. of Teacher Education. Title and description from dissertation home page (viewed on July 16, 2010). Document formatted into pages; contains viii, 82 pages. Includes bibliographical references (p. 79-81).

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2

Watson, Elizabeth M. "Changes in Bone Mineral Density and Biomarkers of Bone Turnover with Calcium Supplementation During Initial Military Cadet Exercise Training." Thesis, Virginia Tech, 2001. http://hdl.handle.net/10919/42379.

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Osteoporosis is a condition involving decreased bone mineral density (BMD) and increased fragility of the skeletal system. Osteoporosis affects ~75 million individuals in the United States, Europe, and Japan. In the United States alone, hip fractures affect 500,000 individuals per year, and annual healthcare costs for osteoporotic fractures are approximately $14 billion. A high peak BMD can prevent or delay the onset of osteoporosis and its complications. Exercise and diet may affect peak BMD by as much as 20 to 40% each and have been identified as the two most important controllable factor

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3

Achitouv, Ixandra. "Halo mass function of dark matter halos : imprints of the initial matter density field and of the non-linear collapse." Paris 7, 2012. http://www.theses.fr/2012PA077245.

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4

Lokre, Chinmay Vivekananda. "Effect of Density, Initial Water Content, Drying Temperature, Layer Thickness, and Plasticity Characteristics on Shrinkage Crack Development in Clay Soils: An Experimental Study." Kent State University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=kent1557423451910154.

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5

Li, Lijie. "Effects of initial microbial density on disinfection efficiency in a continuous flow system and validation of disinfection batch kinetics in a continuous flow system /." Philadelphia, Pa. : Drexel University, 2004. http://dspace.library.drexel.edu/handle/1860/266.

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6

Sapaz, Burak. "Lateral Versus Vertical Swell Pressures In Expansive Soils." Master's thesis, METU, 2004. http://etd.lib.metu.edu/upload/1053040/index.pdf.

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Expansive or swelling soils, exist in many part of the world, show excessive volume changes with increasing water content. As a result of this volume increase, expansive soils apply vertical and lateral pressures to the structures located or buried in these regions. Many researchs have been carried out on vertical swelling pressures helping to the engineers to design structures withstanding on these stresses. However, lateral swell behaviour of swelling soils have not been fully understood yet. Structures such as<br>basement walls, water tanks, canals, tunnels, underground conduits and swimmin

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7

Schweigert, Igor Vitalyevich. "Ab initio Density Functional Theory." [Gainesville, Fla.] : University of Florida, 2005. http://purl.fcla.edu/fcla/etd/UFE0011614.

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8

Scheid, Philippe. "Investigation of light–induced ultrafast magnetization dynamics using ab initio methods." Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0166.

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Cette thèse commence par une revue de l’état actuel de l’expérimentation et de la théorie liées à la désaimantation ultrarapide induite par de la lumière, ainsi qu'au retournement tout optique dépendant de l'hélicité. Ceci est suivi d’un aperçu de la théorie de la fonctionnelle de la densité, sur laquelle repose la plupart des travaux rapportés par la suite. La première partie des résultats concerne l’étude de l’effet d’une élévation de la température électronique sur les propriétés de la matière aimantée, et plus précisément Ni, Co, Fe et FePt. Nous montrons que le moment magnétique de chaque

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9

Kvashnin, Yaroslav. "Ab initio theory of ferromagnetic transition metals and alloys under high pressure." Thesis, Grenoble, 2013. http://www.theses.fr/2013GRENY032/document.

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Le sujet de cette thèse porte sur l'étude des propriétés magnétiques de métaux de transition et leurs alliages sous haute pression au moyen de calculs ab initio. D'abord, les résultats de mesures de dichroïsme magnétique circulaire des rayons X (XMCD) au seuil K du nickel et du cobalt sont interprétés. Je montre que les données expérimentales doivent être comparées à celle de l'aimantation d'orbite projetée sur les états ``p''. Je mets en avant que la pression affecte différemment le spin et le moment orbitalaire. Dans le cas de l'alliage FeCo, la transition structurelle s'effectue sous une pr

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10

Do, Amaral De Andrade Sophia Gustavo. "Etude ab-initio de la réponse diélectrique de pérovskites à haute permitivité diélectrique pour le stockage de l'énergie." Thesis, Pau, 2014. http://www.theses.fr/2014PAUU3001/document.

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Des facteurs fondamentaux pour la performance de matériaux à haute permittivité basés sur des pérovskites sont étudiés par des techniques ab-initio. L’anomalie diélectrique géante à 0K des pérovskites est investiguée aux niveaux Hartree-Fock, Théorie de la Fonctionnelle de la Densité et méthodes hybrides, en termes de la stabilité thermodynamique des phases, des contributions structurales et vibrationnelles et des charges effectives de Born. Le mode mou actif en infra-rouge est responsable par l’anomalie et des méthodes hybrides sont nécessaires pour reproduire les données expérimentales. L’év

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11

Li, Zhi. "Ab initio study of the supercritical state of iron." Thesis, Lyon, 2021. http://www.theses.fr/2021LYSEN003.

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Le fer, en tant que brique élémentaire de la Terre, a reçu beaucoup d’attentions. Des efforts considérables ont été mis en œuvre pour déterminer ses propriétés thermodynamiques et thermophysiques à des conditions atteignant celles du noyau terrestre. Cependant, ses propriétés physiques dans le domaine des faibles densités sont moins explorées, et il manque en particulier la position de la courbe d’équilibre liquide-gaz et du point critique. Les informations manquantes entravent le développement d’une équation d’états complète qui couvrirait l’état de détente post onde de choc, et donc empêchen

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12

Tam, Mary Christina. "Ab initio Calculations of Optical Rotation." Diss., Virginia Tech, 2006. http://hdl.handle.net/10919/27214.

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Coupled cluster (CC) and density functional theory (DFT) are highly regarded as robust quantum chemical methods for accurately predicting a wide variety of properties, such as molecular structures, thermochemical data, vibrational spectra, etc., but there has been little focus on the theoretical prediction of optical rotation. This property, also referred to as circular birefringence, is inherent to all chiral molecules and occurs because such samples exhibit different refractive indices for left- and right- circularly polarized light. This thesis focuses on the theoretical prediction of thi

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13

Rouf, S. A. (Syed Awais). "Paramagnetic NMR chemical shift theory:combined ab initio/density-functional theory method." Doctoral thesis, University of Oulu, 2017. http://urn.fi/urn:isbn:9789526216850.

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Abstract In this thesis, the classic Kurland-McGarvey theory for the nuclear magnetic resonance (NMR) chemical shift is presented in a modern framework for paramagnetic systems containing one or more unpaired electrons. First-principles computations are carried out for the NMR shielding tensors in paramagnetic transition-metal complexes. A combined ab initio/density-functional theory (DFT) approach is applied to obtain the necessary electron paramagnetic resonance (EPR) property tensors, i.e., the g-tensor, zero-field splitting tensor (D) and hyperfine coupling tensors (A). In DFT, both the ge

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14

Li, Zheng. "Accelerating Catalyst Discovery via Ab Initio Machine Learning." Diss., Virginia Tech, 2019. http://hdl.handle.net/10919/95915.

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In recent decades, machine learning techniques have received an explosion of interest in the domain of high-throughput materials discovery, which is largely attributed to the fastgrowing development of quantum-chemical methods and learning algorithms. Nevertheless, machine learning for catalysis is still at its initial stage due to our insufficient knowledge of the structure-property relationships. In this regard, we demonstrate a holistic machine-learning framework as surrogate models for the expensive density functional theory to facilitate the discovery of high-performance catalysts. The fr

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15

Leggott, Richard James. "On AB initio solutions to the phase problem for macromolecular crystallography." Thesis, University of York, 1996. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.336841.

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16

Elgammal, Karim. "Density Functional Theory Calculations of Graphene based Humidity and Carbon Dioxide Sensors." Licentiate thesis, KTH, Materialfysik, MF, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-180761.

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Graphene has many interesting physical properties which makes it useful for plenty of applications. In this work we investigate the possibility of using graphene as a carbon dioxide and humidity sensor. Carbon dioxide and water adsorbates are modeled on top of the surface of a graphene sheet, which themselves lie on one of two types of silica substrates or sapphire substrate. We evaluate the changes in the electronic and structural properties of the graphene sheet in the presence of the described adsorbates as well as the accompanying substrate. We perform the study using ab-initio calculation

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17

Rolke, James M. "Orbital electron density from electron momentum spectroscopy : comparison with AB initio calculations." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/nq25146.pdf.

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18

Griffin, Tim Robert. "Ab initio and density functional theory study of the Monsanto catalytic cycle." Thesis, University of Sheffield, 1997. http://etheses.whiterose.ac.uk/3445/.

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The results of an effective core potential ab initio and Density Functional Theory (DFT) quantum mechanical study of the rhodium- and iodide- catalysed Monsanto acetic acid cycle are presented. The geometries and energetics of the intermediates and transition states have been determined for the key steps of the cycle. The potential influence of variables such as solvent and ligands, and the controlling electronic structure features have been examined. Theoretical data for the analogous iridium system are also reported. The lowest energy transition state determined at the restricted Hartree-Foc

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19

Cazzaniga, M. "Ab initio approach to density response and excitation spectra in metallic systems." Doctoral thesis, Università degli Studi di Milano, 2008. http://hdl.handle.net/2434/60385.

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In this thesis I propose a detailed discussion of the calculation of the dielectric response of metallic systems. We mainly performed simulations of Al and Na, since their near free-electron like behaviour permits also a comparison with the results of the HEG model. On the other hand, we also explored the possibility that our methods could be applied to more complex system. In this direction we performed calculation of the optical properties of ferromagnetic Fe, which includes the additional complexity of the presence of the 3d electrons. We also tried to understand if the accuracy of ab

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20

Chaker, Ziyad. "Etude par dynamique moléculaire ab initio des propriétés magnétiques, électroniques et structurales des matériaux lamellaires hybrides organiques-inorganiques." Thesis, Strasbourg, 2017. http://www.theses.fr/2017STRAE016/document.

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Les matériaux hybrides organiques-inorganiques forment une classe de systèmes dans lesquels plusieurs types de molécules organiques peuvent être insérées au sein d'une structure dite d’accueil, souvent de nature inorganique. C'est dans ce contexte que s'inscrit notre étude théorique de ces matériaux, utilisant les méthodes de la théorie de la fonctionnelle de la densité (DFT), jointes aux techniques de dynamique moléculaire (MD) dans l'approche dite de dynamique moléculaire ab initio. Nous avons développé un protocole permettant d'étudier l'évolution des propriétés de matériaux hybrides spécif

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21

Casalenuovo, Kristen. "Density Functional Investigations of Pure and Ligated Clusters." VCU Scholars Compass, 2009. http://scholarscompass.vcu.edu/etd/1788.

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Atomic clusters are attractive candidates for building motifs for new nano-assembled materials with desirable properties. At this nano-regime of matter, the size, shape, and composition of clusters changes their electronic structure and hence their properties. Computational modeling must work hand in hand with experiment to provide robust descriptions of the geometries and energetics of atomic clusters and how they might behave in a nano-assembled material. To this end, we have investigated three distinct species as model systems: antimony oxides SbxOy (x = 1, 2; y = 0 - 3), metal ion-solvent

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22

Esler, William Kevin. "On the development and application of indirect site indexes based on edaphoclimatic variables for commercial forestry in South Africa." Thesis, Stellenbosch : Stellenbosch University, 2012. http://hdl.handle.net/10019.1/20145.

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Thesis (MScFor)--Stellenbosch University, 2012.<br>ENGLISH ABSTRACT: Site Index is used extensively in modern commercial forestry both as an indicator of current and future site potential, but also as a means of site comparison. The concept is deeply embedded into current forest planning processes, and without it empirical growth and yield modelling would not function in its present form. Most commercial forestry companies in South Africa currently spend hundreds of thousands of Rand annually collecting growth stock data via inventory, but spend little or no money on the default compartment da

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23

Hazebroucq, Sandrine. "Etude ab initio de la salvatation d'éléments lourds en milieu sels fondus." Paris 6, 2005. http://www.theses.fr/2005PA066143.

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24

Palmer, Prem. "Structure, Energetics and Reactions of Bisketenes: An Ab Initio and Density Functional Theory Study." Thesis, University of North Texas, 1997. https://digital.library.unt.edu/ark:/67531/metadc501272/.

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The effect of varying substituents on structure and energies of bisketenes was studied using ab initio methods. Effect of substituents on ring closing reaction of bisketenes to the corresponding cyclobutenediones was also studied using ab initio methods. One or two of the following substituents were used to study the effect of varying substituents: BH2, CH3, NH2, OH, F, AlH2, SiH3, PH2, SH, Cl. Studies were done at the Hartree-Fock (HF), Møller-Plesset (MP2), and Density Functional Theory (B3LYP) levels of theory using the 6-31G* basis set.

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25

Ferreira, de Morais Rodrigo. "Study of the stability and the reactivity of Pt and Pt3Ni model catalyst for PEM fuel cells : an ab-initio based multiscale modeling approach." Thesis, Lyon, École normale supérieure, 2011. http://www.theses.fr/2011ENSL0694.

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Les piles à combustible à membrane électrolyte polymère (PEMFC) sont considérées depuis de nombreuses années comme une solution intéressante pour remplacer les moteurs thermiques. Cependant le coˆut élevé du catalyseur et sa faible stabilité limitent la viabilité économique des piles. Le platine pur déposé sur carbone est le catalyseur couramment plus utilisé à la cathode, cependant les nanoparticules d’alliages de type Pt-M (M = Co, Ni ou Fe) sont reconnues depuis peu comme une alternative remarquable en raison d’une meilleure activité et d’une plus grande stabilité au cours de la réaction de

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26

Shukri, Abdullah. "Ab initio electronic stopping power in materials." Palaiseau, Ecole polytechnique, 2015. https://tel.archives-ouvertes.fr/tel-01269549/document.

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Le pouvoir d'arrêt électronique est essentiel pour de nombreuses applications qui dépendent du transport des ions dans la matière, comme par exemple, la protonthérapie utilisée en médecine. Tandis que de nombreuses données expérimentales sont disponibles pour les élements purs, les données sont beaucoup plus parcellaires pour les matériaux binaires. Au cours de cette thèse, nous avons développé une approche numérique complètement ab initio fondée sur l'approximation de la réponse linéaire dans le cadre de la théorie de la fonctionnelle de la densité dépendente du temps, afin de prédire le pouv

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27

Kuhlman, Andrew. "An Ab-Initio Study on the Chemical Modification of Raman Spectra of Organic Adsorbates on Semiconductor Surfaces." Bowling Green State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=bgsu1402334244.

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28

Kim, Duck Young. "Ab initio Lattice Dynamics : Hydrogen-dense and Other Materials." Doctoral thesis, Uppsala universitet, Institutionen för fysik och materialvetenskap, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-9535.

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This thesis presents a theoretical study of materials under high pressure using ab initio lattice dynamics based on density functional theory and density functional perturbation theory using both super-cell and linear response approach. Ab initio lattice dynamics using super-cell approach is applied to compare our theoretical predictions with experimental findings. Phonon dispersion curves of fcc α-γ cerium are calculated and compared with inelastic X-ray scattering data. Pressure dependency of phonon density of states in two cubic phases TiO2 allows us to assign the observed cubic phase in ex

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29

Markov, Maksim. "Prediction of thermal conductivity and strategies for heat transport reduction in bismuth : an ab initio study." Thesis, Université Paris-Saclay (ComUE), 2016. http://www.theses.fr/2016SACLX010/document.

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Cette thèse de doctorat porte sur l'étude théorique de la conductivité thermique du réseau dans le bismuth semi-métallique et sur les stratégies pour réduire la conductivité thermique en vue d'applications pour réduire l'échauffement dans les circuits électroniques, et pour la thermoélectricité. J'ai utilisé des méthodes avancées de résolution de l'équation de transport de Boltzmann pour les phonons, et de calcul ab initio des éléments de matrice de l'interaction phonon-phonon. J'ai calculé la dépendance en température de la conductivité thermique du réseau dans le matériau en volume en excell

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30

Yu, Lantao. "Optimisation par inclusion, alliage et dopage des matériaux thermoélectriques d'intérêt - application des méthodes ab initio et de dynamique moléculaire." Thesis, Université Paris-Saclay (ComUE), 2018. http://www.theses.fr/2018SACLS056/document.

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La thermoélectricité est considérée comme une source prometteuse de l'énergie puisqu'elle est capable de convertir directement la chaleur en électricité. Ceci permet de récupérer la chaleur dissipée sans causer de la pollution. Cependant, les options applicatives à grande échelle sont encore en restriction en raison du faible rendement de conversion thermoélectrique. Par conséquent, de nombreux travaux de recherche sont consacrés à l'amélioration de la performance thermoélectrique de différents matériaux, qui est caractérisée par la figure de mérite ZT. Un ZT favorable comprend simultanément u

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31

Mayo, Martin. "Ab initio anode materials discovery for Li- and Na-ion batteries." Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/270545.

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This thesis uses first principles techniques, mainly the ab initio random structure searching method (AIRSS), to study anode materials for lithium- and sodium- ion batteries (LIBs and NIBs, respectively). Initial work relates to a theoretical structure prediction study of the lithium and sodium phosphide systems in the context of phosphorus anodes as candidates for LIBs and NIBs. The work reveals new Li-P and Na-P phases, some of which can be used to better interpret previous experimental results. By combining AIRSS searches with a high-throughput screening search from structures in the Inorga

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32

LIN, HE. "Ab initio study of organic molecules adsorbed on technologically relevant Surfaces." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2016. http://hdl.handle.net/10281/127444.

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In this thesis we investigated materials of relevance to photovoltaics and organic electronics, and the studied systems involving surfaces with technological applications, such as graphene and TiO2 . We make use of the density functional theory (DFT) to calculate the structural and electronic properties of the system, and the Ab initio molecular dynamics to check the temperature dependent effects. Finally, we simulate the core excited spectroscopic measurements by the transition potential approach and use the Time-Dependent DFT to calculate the optical absorption coefficient. We first fo

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33

Poddey, Alexander [Verfasser]. "Nonspherical deformed atomic fragments and nonselfconsistent density functionals from ab initio / vorgelegt von Alexander Poddey." [Clausthal-Zellerfeld] : [Univ.-Bibliothek], 2008. http://d-nb.info/992157854/34.

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34

Lundie, M. J. "Optical properties of reduced graphene oxide : insights from ab initio and hybrid density functional theory." Thesis, University of Salford, 2016. http://usir.salford.ac.uk/40785/.

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Graphene, despite its many remarkable material properties, is fundamentally limited for many photonic and microelectronic applications due to its semi-metallic nature. Chemical functionalisation of graphene affords one route toward opening an energy gap, potentially extending its utility to these areas. Graphene oxide strongly absorbs in the ultraviolet range and reduction by various chemical treatments has been demonstrated to shift the absorption peak toward the visible spectrum. Photoluminescence emission has also been observed across the spectrum from ultraviolet to infrared, further sugge

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35

Persson, Kristin Aslaug. "Thermodynamical and Dynamical Instabilities from Ab initio Electronic-Structure Calculations." Doctoral thesis, KTH, Physics, 2001. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-3137.

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36

Sassi, Michel. "Etude ab-initio d'arrangements moléculaires auto-assemblés sur surfaces métalliques." Aix-Marseille 3, 2010. http://www.theses.fr/2010AIX30028.

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Nous effectuons des calculs de structure électronique basés sur la Théorie de la Fonctionnelle Densité (DFT). Ce travail porte principalement sur le mécanisme d'adsorption d'arrangements moléculaires auto-assemblés, comme le réseau de mélamine-PTCDI, sur des surfaces métalliques. L'accent est mis sur l'influence mutuelle entre les liaisons intermoléculaires et les interactions molécule-surface. Nous avons aussi considéré des réactions de polymérisation sur des surfaces. Les molécules de BDBA polymérisent sur une surface d'argent (111) via des réactions de déshydratation successives. Un modèle

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Pedroza, Luana Sucupira. "Desenvolvimento de novas aproximações para simulações ab initio." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/43/43134/tde-28032011-155857/.

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Simulações computacionais são ferramentas essenciais para a compreensão num nível microscópico de diversos fenômenos que ocorrem na natureza. Em particular, simulações ab initio, isto é, de primeiros princípios, podem predizer novas propriedades e auxiliar na interpretação de resultados experimentais, sem a necessidade de potenciais empíricos os quais são ajustados para uma específica configuração do sistema. No entanto, mesmo para simulações ab initio são necessárias aproximações tanto para o cálculo de estrutura eletrônica quanto para a descrição dos movimentos nucleares. Nesta tese, novas a

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Botti, Silvana. "Electronic excitations in complex systems: beyond density functional theory for real materials." Habilitation à diriger des recherches, Université Claude Bernard - Lyon I, 2010. http://tel.archives-ouvertes.fr/tel-00520068.

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Aujourd'hui il est possible d'étudier à partir des premier principes la réponse sous excitation de matériaux utilisés dans des applications modernes très variés. En effet, grâce à de récents développements théoriques, ainsi qu'à l'optimisation des algorithmes de calcul, les simulations ab initio ne sont plus seulement limitées à des systèmes idéaux simplifiés, mais elles ont finalement l'ambition de capturer toute la complexité de l'échantillon testé dans l'expérience. Dans ce contexte, ce mémoire porte sur l'étude, à l'aide de différentes approches ab initio, des excitations électroniques dan

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39

Laury, Marie L. "Accurate and Reliable Prediction of Energetic and Spectroscopic Properties Via Electronic Structure Methods." Thesis, University of North Texas, 2013. https://digital.library.unt.edu/ark:/67531/metadc500071/.

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Computational chemistry has led to the greater understanding of the molecular world, from the interaction of molecules, to the composition of molecular species and materials. Of the families of computational chemistry approaches available, the main families of electronic structure methods that are capable of accurate and/or reliable predictions of energetic, structural, and spectroscopic properties are ab initio methods and density functional theory (DFT). The focus of this dissertation is to improve the accuracy of predictions and computational efficiency (with respect to memory, disk space,

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40

Porezag, Dirk. "Development of Ab-Initio and Approximate Density Functional Methods and their Application to Complex Fullerene Systems." Doctoral thesis, Universitätsbibliothek Chemnitz, 1997. http://nbn-resolving.de/urn:nbn:de:bsz:ch1-199700253.

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Die Arbeit befasst sich mit Neu- und Weiterentwicklungen von Dichtefunktionalmethoden und deren Anwendung zur Untersuchung von komplexen Systemen aus Fullerenen. Nach einer kurzen Einf¨uhrung in die theoretischen Grundlagen wird zun¨achst das Problem der Konstruktion optimierter lokaler Basiss¨atze aus Gaussfunktionen behandelt. Die Bestimmung der Exponenten und Kontraktionskoeffizienten erfolgt hierbei auf der Grundlage des Variationsprinzips. Die f¨ur verschiedene Systeme berechneten Grundzustandsgeometrien, Bindungs- und Ionisationsenergien, Dipolmomente, Polarisierbarkeiten und Sch

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41

Niesert, Manfred [Verfasser]. "Ab initio calculations of spin-wave excitation spectra from time-dependent density-functional theory / Manfred Niesert." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2012. http://d-nb.info/102156754X/34.

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42

Venter, Gerhard (Gerhard Abraham). "An Ab Initio density functional study of the structure and stability of transition metal ozone complexes." Thesis, Stellenbosch : Stellenbosch University, 2002. http://hdl.handle.net/10019.1/52650.

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Thesis (MSc)--Stellenbosch University, 2002.<br>ENGLISH ABSTRACT: A thorough search through the literature as well as through the Cambridge Crystallographic Structural Database resulted in no examples of a neutral ozone acting as ligand in a complex with any metal. Ionic compounds containing ozonide as anionic species, however, are well known throughout the literature and not surprisingly the only result for 0₃ and a metal in the CCSD was an ionic rubidium ozonide compound. What follows is a systematic study into the result of placing an ozone ligand within complexing distance of a tran

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Ernsting, David. "Electron momentum density studies of the electronic structure of complex systems : measurements and ab initio calculations." Thesis, University of Bristol, 2015. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.687439.

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A method for computing electron momentum densities and Compton profiles from ab initio calculations is presented. This is employed, together with the momentum density spectroscopy known as Compton scattering to investigate the electronic structure of MgCNi3. A method for computing the positron state within a material is also presented. In our method for computing the electron momentum density, reciprocal space is divided into optimally-shaped tetrahedra for interpolation, and the linear tetrahedron method is used to obtain the momentum density and its projections such as Compton profiles. Resu

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Demiroglu, Ilker. "Ab Initio Studies Of Pentacene On Ag(111) Surfaces." Master's thesis, METU, 2010. http://etd.lib.metu.edu.tr/upload/2/12611425/index.pdf.

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In this work pentacene adsorption on both flat and stepped Ag(111) surfaces were investigated by using Density Functional Theory within Projected Augmented Wave method. On the flat Ag(111) surface favorable adsorption site for a single pentacene molecule was determined to be the bridge site with an angle of 60&amp<br>#9702<br>between pentacene molecular long axis and [011] lattice direction. Potential energy surface was found to be flat, especially along lattice directions. Diffusion and rotation barriers for pentacene on this surface were found to be smaller than 40 meV indicating the possibi

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Hernandez, Jean-Alexis. "Ab initio modeling of dense water ices at extreme conditions of pressure and temperature." Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEN028/document.

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Dans cette thèse, nous étudions la stabilité et les propriétés des glaces d’eau de haute pression (entre 5 et 300 GPa) et de haute température (entre 300 et 2000 K) comportant ou non des inclusions de NaCl dans leur structure cristalline. Pour attendre ces conditions propres aux intérieurs des exoplanètes océans, nous utilisons une approche théorique basée sur des dynamiques moléculaires ab initio. Nous montrons que l’analyse de la dynamique des liaisons entre hydrogènes et oxygènes permet de distinguer toutes les phases de la glace présentant une structure cubique volume-centrée. En particuli

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Sulpizi, Marialore. "Ab initio studies of targets for pharmaceutical intervention." Doctoral thesis, SISSA, 2001. http://hdl.handle.net/20.500.11767/4280.

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In this thesis we further explore the capability of first principle methods to provide insights on drug/target interactions in different contexts. In the first part of this work, we address the issue whether OFT methods can be used as a potential tool for drug-screening. First principle calculations are particularly interesting for screening the energetics of drug/target interactions, as they do not involve the painstaking procedure of developing each set of new parameters for each novel drug. In this context, we use ab initio_ methods as a novel tool to determine a scoring function in a

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Sarmiento, Pérez Rafael. "Ab initio prediction of crystalline phases and electronic properties of alloys and other compounds." Thesis, Lyon 1, 2015. http://www.theses.fr/2015LYO10155/document.

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La thèse présente une étude dans le cadre de la conception ab initio de nouveaux matériaux, avec des applications aux alliages intermétalliques et semi-conducteurs, aux oxydes transparents conducteurs et aux solides moléculaires. Des simulations avec la méthode Minima Hopping combinée avec la théorie de la fonctionnelle de la densité ont été utilisées pour trouver des nouveaux composés dans les diagrammes de phase des composés binaires de Lithium-Aluminium et Sodium-Or, aussi bien que des géométries de faible symétrie de CuBO2 à plus basses énergies que la structure delafossite qui était consi

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Park, Junbum. "Monte Carlo simulations of phonon transport in nanostructures based on ab-initio methods." Electronic Thesis or Diss., université Paris-Saclay, 2024. http://www.theses.fr/2024UPAST068.

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Alors que la tendance à la miniaturisation des appareils électroniques se poursuit, la compréhension du transport de chaleur à l'échelle nanométrique devient de plus en plus cruciale pour développer des systèmes fiables et économes en énergie. La loi de Fourier conventionnelle ne parvient pas à capturer la dynamique complexe du transport de chaleur basé sur les phonons dans de tels dispositifs miniaturisés. Avec la recherche de dispositifs plus compacts et plus performants, l'exploration de matériaux alternatifs au-delà du silicium est tout aussi essentielle, en se concentrant sur leurs propri

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Brémond, Eric. "Simulation ab initio de spectres UV-visibles." Phd thesis, Université Pierre et Marie Curie - Paris VI, 2012. http://pastel.archives-ouvertes.fr/pastel-00760600.

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Les facteurs de réponse UV-visible sont des éléments clés utilisés en chimie analytique afin d'évaluer les proportions des différents constituants d'un mélange. Particulièrement prisés par le monde de l'industrie, ces facteurs sont le plus souvent difficiles à obtenir, surtout lorsque les composés mis en jeu sont des impuretés difficiles à isoler ou à synthétiser. Dans ce contexte, la chimie théorique, et plus particulièrement la Théorie de la Fonctionnelle de la Densité Dépendant du Temps peut devenir un atout non négligeable, capable d'apporter des réponses en un minimum de temps. Afin de pa

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Diebel, Milan. "Application of ab-initio calculations to modeling of nanoscale diffusion and activation in silicon /." Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/9727.

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